aboutsummaryrefslogtreecommitdiff
path: root/libcpp/lex.c
blob: 56ac3a1dd73b10c64c5832153ebb8af0a9dcba5d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
/* CPP Library - lexical analysis.
   Copyright (C) 2000-2020 Free Software Foundation, Inc.
   Contributed by Per Bothner, 1994-95.
   Based on CCCP program by Paul Rubin, June 1986
   Adapted to ANSI C, Richard Stallman, Jan 1987
   Broken out to separate file, Zack Weinberg, Mar 2000

This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3, or (at your option) any
later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

#include "config.h"
#include "system.h"
#include "cpplib.h"
#include "internal.h"

enum spell_type
{
  SPELL_OPERATOR = 0,
  SPELL_IDENT,
  SPELL_LITERAL,
  SPELL_NONE
};

struct token_spelling
{
  enum spell_type category;
  const unsigned char *name;
};

static const unsigned char *const digraph_spellings[] =
{ UC"%:", UC"%:%:", UC"<:", UC":>", UC"<%", UC"%>" };

#define OP(e, s) { SPELL_OPERATOR, UC s  },
#define TK(e, s) { SPELL_ ## s,    UC #e },
static const struct token_spelling token_spellings[N_TTYPES] = { TTYPE_TABLE };
#undef OP
#undef TK

#define TOKEN_SPELL(token) (token_spellings[(token)->type].category)
#define TOKEN_NAME(token) (token_spellings[(token)->type].name)

static void add_line_note (cpp_buffer *, const uchar *, unsigned int);
static int skip_line_comment (cpp_reader *);
static void skip_whitespace (cpp_reader *, cppchar_t);
static void lex_string (cpp_reader *, cpp_token *, const uchar *);
static void save_comment (cpp_reader *, cpp_token *, const uchar *, cppchar_t);
static void store_comment (cpp_reader *, cpp_token *);
static void create_literal (cpp_reader *, cpp_token *, const uchar *,
			    unsigned int, enum cpp_ttype);
static bool warn_in_comment (cpp_reader *, _cpp_line_note *);
static int name_p (cpp_reader *, const cpp_string *);
static tokenrun *next_tokenrun (tokenrun *);

static _cpp_buff *new_buff (size_t);


/* Utility routine:

   Compares, the token TOKEN to the NUL-terminated string STRING.
   TOKEN must be a CPP_NAME.  Returns 1 for equal, 0 for unequal.  */
int
cpp_ideq (const cpp_token *token, const char *string)
{
  if (token->type != CPP_NAME)
    return 0;

  return !ustrcmp (NODE_NAME (token->val.node.node), (const uchar *) string);
}

/* Record a note TYPE at byte POS into the current cleaned logical
   line.  */
static void
add_line_note (cpp_buffer *buffer, const uchar *pos, unsigned int type)
{
  if (buffer->notes_used == buffer->notes_cap)
    {
      buffer->notes_cap = buffer->notes_cap * 2 + 200;
      buffer->notes = XRESIZEVEC (_cpp_line_note, buffer->notes,
                                  buffer->notes_cap);
    }

  buffer->notes[buffer->notes_used].pos = pos;
  buffer->notes[buffer->notes_used].type = type;
  buffer->notes_used++;
}


/* Fast path to find line special characters using optimized character
   scanning algorithms.  Anything complicated falls back to the slow
   path below.  Since this loop is very hot it's worth doing these kinds
   of optimizations.

   One of the paths through the ifdefs should provide 

     const uchar *search_line_fast (const uchar *s, const uchar *end);

   Between S and END, search for \n, \r, \\, ?.  Return a pointer to
   the found character.

   Note that the last character of the buffer is *always* a newline,
   as forced by _cpp_convert_input.  This fact can be used to avoid
   explicitly looking for the end of the buffer.  */

/* Configure gives us an ifdef test.  */
#ifndef WORDS_BIGENDIAN
#define WORDS_BIGENDIAN 0
#endif

/* We'd like the largest integer that fits into a register.  There's nothing
   in <stdint.h> that gives us that.  For most hosts this is unsigned long,
   but MS decided on an LLP64 model.  Thankfully when building with GCC we
   can get the "real" word size.  */
#ifdef __GNUC__
typedef unsigned int word_type __attribute__((__mode__(__word__)));
#else
typedef unsigned long word_type;
#endif

/* The code below is only expecting sizes 4 or 8.
   Die at compile-time if this expectation is violated.  */
typedef char check_word_type_size
  [(sizeof(word_type) == 8 || sizeof(word_type) == 4) * 2 - 1];

/* Return X with the first N bytes forced to values that won't match one
   of the interesting characters.  Note that NUL is not interesting.  */

static inline word_type
acc_char_mask_misalign (word_type val, unsigned int n)
{
  word_type mask = -1;
  if (WORDS_BIGENDIAN)
    mask >>= n * 8;
  else
    mask <<= n * 8;
  return val & mask;
}

/* Return X replicated to all byte positions within WORD_TYPE.  */

static inline word_type
acc_char_replicate (uchar x)
{
  word_type ret;

  ret = (x << 24) | (x << 16) | (x << 8) | x;
  if (sizeof(word_type) == 8)
    ret = (ret << 16 << 16) | ret;
  return ret;
}

/* Return non-zero if some byte of VAL is (probably) C.  */

static inline word_type
acc_char_cmp (word_type val, word_type c)
{
#if defined(__GNUC__) && defined(__alpha__)
  /* We can get exact results using a compare-bytes instruction.  
     Get (val == c) via (0 >= (val ^ c)).  */
  return __builtin_alpha_cmpbge (0, val ^ c);
#else
  word_type magic = 0x7efefefeU;
  if (sizeof(word_type) == 8)
    magic = (magic << 16 << 16) | 0xfefefefeU;
  magic |= 1;

  val ^= c;
  return ((val + magic) ^ ~val) & ~magic;
#endif
}

/* Given the result of acc_char_cmp is non-zero, return the index of
   the found character.  If this was a false positive, return -1.  */

static inline int
acc_char_index (word_type cmp ATTRIBUTE_UNUSED,
		word_type val ATTRIBUTE_UNUSED)
{
#if defined(__GNUC__) && defined(__alpha__) && !WORDS_BIGENDIAN
  /* The cmpbge instruction sets *bits* of the result corresponding to
     matches in the bytes with no false positives.  */
  return __builtin_ctzl (cmp);
#else
  unsigned int i;

  /* ??? It would be nice to force unrolling here,
     and have all of these constants folded.  */
  for (i = 0; i < sizeof(word_type); ++i)
    {
      uchar c;
      if (WORDS_BIGENDIAN)
	c = (val >> (sizeof(word_type) - i - 1) * 8) & 0xff;
      else
	c = (val >> i * 8) & 0xff;

      if (c == '\n' || c == '\r' || c == '\\' || c == '?')
	return i;
    }

  return -1;
#endif
}

/* A version of the fast scanner using bit fiddling techniques.
 
   For 32-bit words, one would normally perform 16 comparisons and
   16 branches.  With this algorithm one performs 24 arithmetic
   operations and one branch.  Whether this is faster with a 32-bit
   word size is going to be somewhat system dependent.

   For 64-bit words, we eliminate twice the number of comparisons
   and branches without increasing the number of arithmetic operations.
   It's almost certainly going to be a win with 64-bit word size.  */

static const uchar * search_line_acc_char (const uchar *, const uchar *)
  ATTRIBUTE_UNUSED;

static const uchar *
search_line_acc_char (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
{
  const word_type repl_nl = acc_char_replicate ('\n');
  const word_type repl_cr = acc_char_replicate ('\r');
  const word_type repl_bs = acc_char_replicate ('\\');
  const word_type repl_qm = acc_char_replicate ('?');

  unsigned int misalign;
  const word_type *p;
  word_type val, t;
  
  /* Align the buffer.  Mask out any bytes from before the beginning.  */
  p = (word_type *)((uintptr_t)s & -sizeof(word_type));
  val = *p;
  misalign = (uintptr_t)s & (sizeof(word_type) - 1);
  if (misalign)
    val = acc_char_mask_misalign (val, misalign);

  /* Main loop.  */
  while (1)
    {
      t  = acc_char_cmp (val, repl_nl);
      t |= acc_char_cmp (val, repl_cr);
      t |= acc_char_cmp (val, repl_bs);
      t |= acc_char_cmp (val, repl_qm);

      if (__builtin_expect (t != 0, 0))
	{
	  int i = acc_char_index (t, val);
	  if (i >= 0)
	    return (const uchar *)p + i;
	}

      val = *++p;
    }
}

/* Disable on Solaris 2/x86 until the following problem can be properly
   autoconfed:

   The Solaris 10+ assembler tags objects with the instruction set
   extensions used, so SSE4.2 executables cannot run on machines that
   don't support that extension.  */

#if (GCC_VERSION >= 4005) && (__GNUC__ >= 5 || !defined(__PIC__)) && (defined(__i386__) || defined(__x86_64__)) && !(defined(__sun__) && defined(__svr4__))

/* Replicated character data to be shared between implementations.
   Recall that outside of a context with vector support we can't
   define compatible vector types, therefore these are all defined
   in terms of raw characters.  */
static const char repl_chars[4][16] __attribute__((aligned(16))) = {
  { '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n',
    '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n' },
  { '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r',
    '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r' },
  { '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\',
    '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\' },
  { '?', '?', '?', '?', '?', '?', '?', '?',
    '?', '?', '?', '?', '?', '?', '?', '?' },
};

/* A version of the fast scanner using MMX vectorized byte compare insns.

   This uses the PMOVMSKB instruction which was introduced with "MMX2",
   which was packaged into SSE1; it is also present in the AMD MMX
   extension.  Mark the function as using "sse" so that we emit a real
   "emms" instruction, rather than the 3dNOW "femms" instruction.  */

static const uchar *
#ifndef __SSE__
__attribute__((__target__("sse")))
#endif
search_line_mmx (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
{
  typedef char v8qi __attribute__ ((__vector_size__ (8)));
  typedef int __m64 __attribute__ ((__vector_size__ (8), __may_alias__));

  const v8qi repl_nl = *(const v8qi *)repl_chars[0];
  const v8qi repl_cr = *(const v8qi *)repl_chars[1];
  const v8qi repl_bs = *(const v8qi *)repl_chars[2];
  const v8qi repl_qm = *(const v8qi *)repl_chars[3];

  unsigned int misalign, found, mask;
  const v8qi *p;
  v8qi data, t, c;

  /* Align the source pointer.  While MMX doesn't generate unaligned data
     faults, this allows us to safely scan to the end of the buffer without
     reading beyond the end of the last page.  */
  misalign = (uintptr_t)s & 7;
  p = (const v8qi *)((uintptr_t)s & -8);
  data = *p;

  /* Create a mask for the bytes that are valid within the first
     16-byte block.  The Idea here is that the AND with the mask
     within the loop is "free", since we need some AND or TEST
     insn in order to set the flags for the branch anyway.  */
  mask = -1u << misalign;

  /* Main loop processing 8 bytes at a time.  */
  goto start;
  do
    {
      data = *++p;
      mask = -1;

    start:
      t = __builtin_ia32_pcmpeqb(data, repl_nl);
      c = __builtin_ia32_pcmpeqb(data, repl_cr);
      t = (v8qi) __builtin_ia32_por ((__m64)t, (__m64)c);
      c = __builtin_ia32_pcmpeqb(data, repl_bs);
      t = (v8qi) __builtin_ia32_por ((__m64)t, (__m64)c);
      c = __builtin_ia32_pcmpeqb(data, repl_qm);
      t = (v8qi) __builtin_ia32_por ((__m64)t, (__m64)c);
      found = __builtin_ia32_pmovmskb (t);
      found &= mask;
    }
  while (!found);

  __builtin_ia32_emms ();

  /* FOUND contains 1 in bits for which we matched a relevant
     character.  Conversion to the byte index is trivial.  */
  found = __builtin_ctz(found);
  return (const uchar *)p + found;
}

/* A version of the fast scanner using SSE2 vectorized byte compare insns.  */

static const uchar *
#ifndef __SSE2__
__attribute__((__target__("sse2")))
#endif
search_line_sse2 (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
{
  typedef char v16qi __attribute__ ((__vector_size__ (16)));

  const v16qi repl_nl = *(const v16qi *)repl_chars[0];
  const v16qi repl_cr = *(const v16qi *)repl_chars[1];
  const v16qi repl_bs = *(const v16qi *)repl_chars[2];
  const v16qi repl_qm = *(const v16qi *)repl_chars[3];

  unsigned int misalign, found, mask;
  const v16qi *p;
  v16qi data, t;

  /* Align the source pointer.  */
  misalign = (uintptr_t)s & 15;
  p = (const v16qi *)((uintptr_t)s & -16);
  data = *p;

  /* Create a mask for the bytes that are valid within the first
     16-byte block.  The Idea here is that the AND with the mask
     within the loop is "free", since we need some AND or TEST
     insn in order to set the flags for the branch anyway.  */
  mask = -1u << misalign;

  /* Main loop processing 16 bytes at a time.  */
  goto start;
  do
    {
      data = *++p;
      mask = -1;

    start:
      t  = __builtin_ia32_pcmpeqb128(data, repl_nl);
      t |= __builtin_ia32_pcmpeqb128(data, repl_cr);
      t |= __builtin_ia32_pcmpeqb128(data, repl_bs);
      t |= __builtin_ia32_pcmpeqb128(data, repl_qm);
      found = __builtin_ia32_pmovmskb128 (t);
      found &= mask;
    }
  while (!found);

  /* FOUND contains 1 in bits for which we matched a relevant
     character.  Conversion to the byte index is trivial.  */
  found = __builtin_ctz(found);
  return (const uchar *)p + found;
}

#ifdef HAVE_SSE4
/* A version of the fast scanner using SSE 4.2 vectorized string insns.  */

static const uchar *
#ifndef __SSE4_2__
__attribute__((__target__("sse4.2")))
#endif
search_line_sse42 (const uchar *s, const uchar *end)
{
  typedef char v16qi __attribute__ ((__vector_size__ (16)));
  static const v16qi search = { '\n', '\r', '?', '\\' };

  uintptr_t si = (uintptr_t)s;
  uintptr_t index;

  /* Check for unaligned input.  */
  if (si & 15)
    {
      v16qi sv;

      if (__builtin_expect (end - s < 16, 0)
	  && __builtin_expect ((si & 0xfff) > 0xff0, 0))
	{
	  /* There are less than 16 bytes left in the buffer, and less
	     than 16 bytes left on the page.  Reading 16 bytes at this
	     point might generate a spurious page fault.  Defer to the
	     SSE2 implementation, which already handles alignment.  */
	  return search_line_sse2 (s, end);
	}

      /* ??? The builtin doesn't understand that the PCMPESTRI read from
	 memory need not be aligned.  */
      sv = __builtin_ia32_loaddqu ((const char *) s);
      index = __builtin_ia32_pcmpestri128 (search, 4, sv, 16, 0);

      if (__builtin_expect (index < 16, 0))
	goto found;

      /* Advance the pointer to an aligned address.  We will re-scan a
	 few bytes, but we no longer need care for reading past the
	 end of a page, since we're guaranteed a match.  */
      s = (const uchar *)((si + 15) & -16);
    }

  /* Main loop, processing 16 bytes at a time.  */
#ifdef __GCC_ASM_FLAG_OUTPUTS__
  while (1)
    {
      char f;

      /* By using inline assembly instead of the builtin,
	 we can use the result, as well as the flags set.  */
      __asm ("%vpcmpestri\t$0, %2, %3"
	     : "=c"(index), "=@ccc"(f)
	     : "m"(*s), "x"(search), "a"(4), "d"(16));
      if (f)
	break;
      
      s += 16;
    }
#else
  s -= 16;
  /* By doing the whole loop in inline assembly,
     we can make proper use of the flags set.  */
  __asm (      ".balign 16\n"
	"0:	add $16, %1\n"
	"	%vpcmpestri\t$0, (%1), %2\n"
	"	jnc 0b"
	: "=&c"(index), "+r"(s)
	: "x"(search), "a"(4), "d"(16));
#endif

 found:
  return s + index;
}

#else
/* Work around out-dated assemblers without sse4 support.  */
#define search_line_sse42 search_line_sse2
#endif

/* Check the CPU capabilities.  */

#include "../gcc/config/i386/cpuid.h"

typedef const uchar * (*search_line_fast_type) (const uchar *, const uchar *);
static search_line_fast_type search_line_fast;

#define HAVE_init_vectorized_lexer 1
static inline void
init_vectorized_lexer (void)
{
  unsigned dummy, ecx = 0, edx = 0;
  search_line_fast_type impl = search_line_acc_char;
  int minimum = 0;

#if defined(__SSE4_2__)
  minimum = 3;
#elif defined(__SSE2__)
  minimum = 2;
#elif defined(__SSE__)
  minimum = 1;
#endif

  if (minimum == 3)
    impl = search_line_sse42;
  else if (__get_cpuid (1, &dummy, &dummy, &ecx, &edx) || minimum == 2)
    {
      if (minimum == 3 || (ecx & bit_SSE4_2))
        impl = search_line_sse42;
      else if (minimum == 2 || (edx & bit_SSE2))
	impl = search_line_sse2;
      else if (minimum == 1 || (edx & bit_SSE))
	impl = search_line_mmx;
    }
  else if (__get_cpuid (0x80000001, &dummy, &dummy, &dummy, &edx))
    {
      if (minimum == 1
	  || (edx & (bit_MMXEXT | bit_CMOV)) == (bit_MMXEXT | bit_CMOV))
	impl = search_line_mmx;
    }

  search_line_fast = impl;
}

#elif defined(_ARCH_PWR8) && defined(__ALTIVEC__)

/* A vection of the fast scanner using AltiVec vectorized byte compares
   and VSX unaligned loads (when VSX is available).  This is otherwise
   the same as the pre-GCC 5 version.  */

ATTRIBUTE_NO_SANITIZE_UNDEFINED
static const uchar *
search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
{
  typedef __attribute__((altivec(vector))) unsigned char vc;

  const vc repl_nl = {
    '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n', 
    '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n'
  };
  const vc repl_cr = {
    '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r', 
    '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r'
  };
  const vc repl_bs = {
    '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\', 
    '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\'
  };
  const vc repl_qm = {
    '?', '?', '?', '?', '?', '?', '?', '?', 
    '?', '?', '?', '?', '?', '?', '?', '?', 
  };
  const vc zero = { 0 };

  vc data, t;

  /* Main loop processing 16 bytes at a time.  */
  do
    {
      vc m_nl, m_cr, m_bs, m_qm;

      data = __builtin_vec_vsx_ld (0, s);
      s += 16;

      m_nl = (vc) __builtin_vec_cmpeq(data, repl_nl);
      m_cr = (vc) __builtin_vec_cmpeq(data, repl_cr);
      m_bs = (vc) __builtin_vec_cmpeq(data, repl_bs);
      m_qm = (vc) __builtin_vec_cmpeq(data, repl_qm);
      t = (m_nl | m_cr) | (m_bs | m_qm);

      /* T now contains 0xff in bytes for which we matched one of the relevant
	 characters.  We want to exit the loop if any byte in T is non-zero.
	 Below is the expansion of vec_any_ne(t, zero).  */
    }
  while (!__builtin_vec_vcmpeq_p(/*__CR6_LT_REV*/3, t, zero));

  /* Restore s to to point to the 16 bytes we just processed.  */
  s -= 16;

  {
#define N  (sizeof(vc) / sizeof(long))

    union {
      vc v;
      /* Statically assert that N is 2 or 4.  */
      unsigned long l[(N == 2 || N == 4) ? N : -1];
    } u;
    unsigned long l, i = 0;

    u.v = t;

    /* Find the first word of T that is non-zero.  */
    switch (N)
      {
      case 4:
	l = u.l[i++];
	if (l != 0)
	  break;
	s += sizeof(unsigned long);
	l = u.l[i++];
	if (l != 0)
	  break;
	s += sizeof(unsigned long);
	/* FALLTHRU */
      case 2:
	l = u.l[i++];
	if (l != 0)
	  break;
	s += sizeof(unsigned long);
	l = u.l[i];
      }

    /* L now contains 0xff in bytes for which we matched one of the
       relevant characters.  We can find the byte index by finding
       its bit index and dividing by 8.  */
#ifdef __BIG_ENDIAN__
    l = __builtin_clzl(l) >> 3;
#else
    l = __builtin_ctzl(l) >> 3;
#endif
    return s + l;

#undef N
  }
}

#elif (GCC_VERSION >= 4005) && defined(__ALTIVEC__) && defined (__BIG_ENDIAN__)

/* A vection of the fast scanner using AltiVec vectorized byte compares.
   This cannot be used for little endian because vec_lvsl/lvsr are
   deprecated for little endian and the code won't work properly.  */
/* ??? Unfortunately, attribute(target("altivec")) is not yet supported,
   so we can't compile this function without -maltivec on the command line
   (or implied by some other switch).  */

static const uchar *
search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
{
  typedef __attribute__((altivec(vector))) unsigned char vc;

  const vc repl_nl = {
    '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n', 
    '\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n'
  };
  const vc repl_cr = {
    '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r', 
    '\r', '\r', '\r', '\r', '\r', '\r', '\r', '\r'
  };
  const vc repl_bs = {
    '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\', 
    '\\', '\\', '\\', '\\', '\\', '\\', '\\', '\\'
  };
  const vc repl_qm = {
    '?', '?', '?', '?', '?', '?', '?', '?', 
    '?', '?', '?', '?', '?', '?', '?', '?', 
  };
  const vc ones = {
    -1, -1, -1, -1, -1, -1, -1, -1,
    -1, -1, -1, -1, -1, -1, -1, -1,
  };
  const vc zero = { 0 };

  vc data, mask, t;

  /* Altivec loads automatically mask addresses with -16.  This lets us
     issue the first load as early as possible.  */
  data = __builtin_vec_ld(0, (const vc *)s);

  /* Discard bytes before the beginning of the buffer.  Do this by
     beginning with all ones and shifting in zeros according to the
     mis-alignment.  The LVSR instruction pulls the exact shift we
     want from the address.  */
  mask = __builtin_vec_lvsr(0, s);
  mask = __builtin_vec_perm(zero, ones, mask);
  data &= mask;

  /* While altivec loads mask addresses, we still need to align S so
     that the offset we compute at the end is correct.  */
  s = (const uchar *)((uintptr_t)s & -16);

  /* Main loop processing 16 bytes at a time.  */
  goto start;
  do
    {
      vc m_nl, m_cr, m_bs, m_qm;

      s += 16;
      data = __builtin_vec_ld(0, (const vc *)s);

    start:
      m_nl = (vc) __builtin_vec_cmpeq(data, repl_nl);
      m_cr = (vc) __builtin_vec_cmpeq(data, repl_cr);
      m_bs = (vc) __builtin_vec_cmpeq(data, repl_bs);
      m_qm = (vc) __builtin_vec_cmpeq(data, repl_qm);
      t = (m_nl | m_cr) | (m_bs | m_qm);

      /* T now contains 0xff in bytes for which we matched one of the relevant
	 characters.  We want to exit the loop if any byte in T is non-zero.
	 Below is the expansion of vec_any_ne(t, zero).  */
    }
  while (!__builtin_vec_vcmpeq_p(/*__CR6_LT_REV*/3, t, zero));

  {
#define N  (sizeof(vc) / sizeof(long))

    union {
      vc v;
      /* Statically assert that N is 2 or 4.  */
      unsigned long l[(N == 2 || N == 4) ? N : -1];
    } u;
    unsigned long l, i = 0;

    u.v = t;

    /* Find the first word of T that is non-zero.  */
    switch (N)
      {
      case 4:
	l = u.l[i++];
	if (l != 0)
	  break;
	s += sizeof(unsigned long);
	l = u.l[i++];
	if (l != 0)
	  break;
	s += sizeof(unsigned long);
	/* FALLTHROUGH */
      case 2:
	l = u.l[i++];
	if (l != 0)
	  break;
	s += sizeof(unsigned long);
	l = u.l[i];
      }

    /* L now contains 0xff in bytes for which we matched one of the
       relevant characters.  We can find the byte index by finding
       its bit index and dividing by 8.  */
    l = __builtin_clzl(l) >> 3;
    return s + l;

#undef N
  }
}

#elif defined (__ARM_NEON) && defined (__ARM_64BIT_STATE)
#include "arm_neon.h"

/* This doesn't have to be the exact page size, but no system may use
   a size smaller than this.  ARMv8 requires a minimum page size of
   4k.  The impact of being conservative here is a small number of
   cases will take the slightly slower entry path into the main
   loop.  */

#define AARCH64_MIN_PAGE_SIZE 4096

static const uchar *
search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
{
  const uint8x16_t repl_nl = vdupq_n_u8 ('\n');
  const uint8x16_t repl_cr = vdupq_n_u8 ('\r');
  const uint8x16_t repl_bs = vdupq_n_u8 ('\\');
  const uint8x16_t repl_qm = vdupq_n_u8 ('?');
  const uint8x16_t xmask = (uint8x16_t) vdupq_n_u64 (0x8040201008040201ULL);

#ifdef __ARM_BIG_ENDIAN
  const int16x8_t shift = {8, 8, 8, 8, 0, 0, 0, 0};
#else
  const int16x8_t shift = {0, 0, 0, 0, 8, 8, 8, 8};
#endif

  unsigned int found;
  const uint8_t *p;
  uint8x16_t data;
  uint8x16_t t;
  uint16x8_t m;
  uint8x16_t u, v, w;

  /* Align the source pointer.  */
  p = (const uint8_t *)((uintptr_t)s & -16);

  /* Assuming random string start positions, with a 4k page size we'll take
     the slow path about 0.37% of the time.  */
  if (__builtin_expect ((AARCH64_MIN_PAGE_SIZE
			 - (((uintptr_t) s) & (AARCH64_MIN_PAGE_SIZE - 1)))
			< 16, 0))
    {
      /* Slow path: the string starts near a possible page boundary.  */
      uint32_t misalign, mask;

      misalign = (uintptr_t)s & 15;
      mask = (-1u << misalign) & 0xffff;
      data = vld1q_u8 (p);
      t = vceqq_u8 (data, repl_nl);
      u = vceqq_u8 (data, repl_cr);
      v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
      w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
      t = vorrq_u8 (v, w);
      t = vandq_u8 (t, xmask);
      m = vpaddlq_u8 (t);
      m = vshlq_u16 (m, shift);
      found = vaddvq_u16 (m);
      found &= mask;
      if (found)
	return (const uchar*)p + __builtin_ctz (found);
    }
  else
    {
      data = vld1q_u8 ((const uint8_t *) s);
      t = vceqq_u8 (data, repl_nl);
      u = vceqq_u8 (data, repl_cr);
      v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
      w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
      t = vorrq_u8 (v, w);
      if (__builtin_expect (vpaddd_u64 ((uint64x2_t)t) != 0, 0))
	goto done;
    }

  do
    {
      p += 16;
      data = vld1q_u8 (p);
      t = vceqq_u8 (data, repl_nl);
      u = vceqq_u8 (data, repl_cr);
      v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
      w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
      t = vorrq_u8 (v, w);
    } while (!vpaddd_u64 ((uint64x2_t)t));

done:
  /* Now that we've found the terminating substring, work out precisely where
     we need to stop.  */
  t = vandq_u8 (t, xmask);
  m = vpaddlq_u8 (t);
  m = vshlq_u16 (m, shift);
  found = vaddvq_u16 (m);
  return (((((uintptr_t) p) < (uintptr_t) s) ? s : (const uchar *)p)
	  + __builtin_ctz (found));
}

#elif defined (__ARM_NEON)
#include "arm_neon.h"

static const uchar *
search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
{
  const uint8x16_t repl_nl = vdupq_n_u8 ('\n');
  const uint8x16_t repl_cr = vdupq_n_u8 ('\r');
  const uint8x16_t repl_bs = vdupq_n_u8 ('\\');
  const uint8x16_t repl_qm = vdupq_n_u8 ('?');
  const uint8x16_t xmask = (uint8x16_t) vdupq_n_u64 (0x8040201008040201ULL);

  unsigned int misalign, found, mask;
  const uint8_t *p;
  uint8x16_t data;

  /* Align the source pointer.  */
  misalign = (uintptr_t)s & 15;
  p = (const uint8_t *)((uintptr_t)s & -16);
  data = vld1q_u8 (p);

  /* Create a mask for the bytes that are valid within the first
     16-byte block.  The Idea here is that the AND with the mask
     within the loop is "free", since we need some AND or TEST
     insn in order to set the flags for the branch anyway.  */
  mask = (-1u << misalign) & 0xffff;

  /* Main loop, processing 16 bytes at a time.  */
  goto start;

  do
    {
      uint8x8_t l;
      uint16x4_t m;
      uint32x2_t n;
      uint8x16_t t, u, v, w;

      p += 16;
      data = vld1q_u8 (p);
      mask = 0xffff;

    start:
      t = vceqq_u8 (data, repl_nl);
      u = vceqq_u8 (data, repl_cr);
      v = vorrq_u8 (t, vceqq_u8 (data, repl_bs));
      w = vorrq_u8 (u, vceqq_u8 (data, repl_qm));
      t = vandq_u8 (vorrq_u8 (v, w), xmask);
      l = vpadd_u8 (vget_low_u8 (t), vget_high_u8 (t));
      m = vpaddl_u8 (l);
      n = vpaddl_u16 (m);
      
      found = vget_lane_u32 ((uint32x2_t) vorr_u64 ((uint64x1_t) n, 
	      vshr_n_u64 ((uint64x1_t) n, 24)), 0);
      found &= mask;
    }
  while (!found);

  /* FOUND contains 1 in bits for which we matched a relevant
     character.  Conversion to the byte index is trivial.  */
  found = __builtin_ctz (found);
  return (const uchar *)p + found;
}

#else

/* We only have one accelerated alternative.  Use a direct call so that
   we encourage inlining.  */

#define search_line_fast  search_line_acc_char

#endif

/* Initialize the lexer if needed.  */

void
_cpp_init_lexer (void)
{
#ifdef HAVE_init_vectorized_lexer
  init_vectorized_lexer ();
#endif
}

/* Returns with a logical line that contains no escaped newlines or
   trigraphs.  This is a time-critical inner loop.  */
void
_cpp_clean_line (cpp_reader *pfile)
{
  cpp_buffer *buffer;
  const uchar *s;
  uchar c, *d, *p;

  buffer = pfile->buffer;
  buffer->cur_note = buffer->notes_used = 0;
  buffer->cur = buffer->line_base = buffer->next_line;
  buffer->need_line = false;
  s = buffer->next_line;

  if (!buffer->from_stage3)
    {
      const uchar *pbackslash = NULL;

      /* Fast path.  This is the common case of an un-escaped line with
	 no trigraphs.  The primary win here is by not writing any
	 data back to memory until we have to.  */
      while (1)
	{
	  /* Perform an optimized search for \n, \r, \\, ?.  */
	  s = search_line_fast (s, buffer->rlimit);

	  c = *s;
	  if (c == '\\')
	    {
	      /* Record the location of the backslash and continue.  */
	      pbackslash = s++;
	    }
	  else if (__builtin_expect (c == '?', 0))
	    {
	      if (__builtin_expect (s[1] == '?', false)
		   && _cpp_trigraph_map[s[2]])
		{
		  /* Have a trigraph.  We may or may not have to convert
		     it.  Add a line note regardless, for -Wtrigraphs.  */
		  add_line_note (buffer, s, s[2]);
		  if (CPP_OPTION (pfile, trigraphs))
		    {
		      /* We do, and that means we have to switch to the
		         slow path.  */
		      d = (uchar *) s;
		      *d = _cpp_trigraph_map[s[2]];
		      s += 2;
		      goto slow_path;
		    }
		}
	      /* Not a trigraph.  Continue on fast-path.  */
	      s++;
	    }
	  else
	    break;
	}

      /* This must be \r or \n.  We're either done, or we'll be forced
	 to write back to the buffer and continue on the slow path.  */
      d = (uchar *) s;

      if (__builtin_expect (s == buffer->rlimit, false))
	goto done;

      /* DOS line ending? */
      if (__builtin_expect (c == '\r', false) && s[1] == '\n')
	{
	  s++;
	  if (s == buffer->rlimit)
	    goto done;
	}

      if (__builtin_expect (pbackslash == NULL, true))
	goto done;

      /* Check for escaped newline.  */
      p = d;
      while (is_nvspace (p[-1]))
	p--;
      if (p - 1 != pbackslash)
	goto done;

      /* Have an escaped newline; process it and proceed to
	 the slow path.  */
      add_line_note (buffer, p - 1, p != d ? ' ' : '\\');
      d = p - 2;
      buffer->next_line = p - 1;

    slow_path:
      while (1)
	{
	  c = *++s;
	  *++d = c;

	  if (c == '\n' || c == '\r')
	    {
	      /* Handle DOS line endings.  */
	      if (c == '\r' && s != buffer->rlimit && s[1] == '\n')
		s++;
	      if (s == buffer->rlimit)
		break;

	      /* Escaped?  */
	      p = d;
	      while (p != buffer->next_line && is_nvspace (p[-1]))
		p--;
	      if (p == buffer->next_line || p[-1] != '\\')
		break;

	      add_line_note (buffer, p - 1, p != d ? ' ': '\\');
	      d = p - 2;
	      buffer->next_line = p - 1;
	    }
	  else if (c == '?' && s[1] == '?' && _cpp_trigraph_map[s[2]])
	    {
	      /* Add a note regardless, for the benefit of -Wtrigraphs.  */
	      add_line_note (buffer, d, s[2]);
	      if (CPP_OPTION (pfile, trigraphs))
		{
		  *d = _cpp_trigraph_map[s[2]];
		  s += 2;
		}
	    }
	}
    }
  else
    {
      while (*s != '\n' && *s != '\r')
	s++;
      d = (uchar *) s;

      /* Handle DOS line endings.  */
      if (*s == '\r' && s != buffer->rlimit && s[1] == '\n')
	s++;
    }

 done:
  *d = '\n';
  /* A sentinel note that should never be processed.  */
  add_line_note (buffer, d + 1, '\n');
  buffer->next_line = s + 1;
}

/* Return true if the trigraph indicated by NOTE should be warned
   about in a comment.  */
static bool
warn_in_comment (cpp_reader *pfile, _cpp_line_note *note)
{
  const uchar *p;

  /* Within comments we don't warn about trigraphs, unless the
     trigraph forms an escaped newline, as that may change
     behavior.  */
  if (note->type != '/')
    return false;

  /* If -trigraphs, then this was an escaped newline iff the next note
     is coincident.  */
  if (CPP_OPTION (pfile, trigraphs))
    return note[1].pos == note->pos;

  /* Otherwise, see if this forms an escaped newline.  */
  p = note->pos + 3;
  while (is_nvspace (*p))
    p++;

  /* There might have been escaped newlines between the trigraph and the
     newline we found.  Hence the position test.  */
  return (*p == '\n' && p < note[1].pos);
}

/* Process the notes created by add_line_note as far as the current
   location.  */
void
_cpp_process_line_notes (cpp_reader *pfile, int in_comment)
{
  cpp_buffer *buffer = pfile->buffer;

  for (;;)
    {
      _cpp_line_note *note = &buffer->notes[buffer->cur_note];
      unsigned int col;

      if (note->pos > buffer->cur)
	break;

      buffer->cur_note++;
      col = CPP_BUF_COLUMN (buffer, note->pos + 1);

      if (note->type == '\\' || note->type == ' ')
	{
	  if (note->type == ' ' && !in_comment)
	    cpp_error_with_line (pfile, CPP_DL_WARNING, pfile->line_table->highest_line, col,
				 "backslash and newline separated by space");

	  if (buffer->next_line > buffer->rlimit)
	    {
	      cpp_error_with_line (pfile, CPP_DL_PEDWARN, pfile->line_table->highest_line, col,
				   "backslash-newline at end of file");
	      /* Prevent "no newline at end of file" warning.  */
	      buffer->next_line = buffer->rlimit;
	    }

	  buffer->line_base = note->pos;
	  CPP_INCREMENT_LINE (pfile, 0);
	}
      else if (_cpp_trigraph_map[note->type])
	{
	  if (CPP_OPTION (pfile, warn_trigraphs)
	      && (!in_comment || warn_in_comment (pfile, note)))
	    {
	      if (CPP_OPTION (pfile, trigraphs))
		cpp_warning_with_line (pfile, CPP_W_TRIGRAPHS,
                                       pfile->line_table->highest_line, col,
				       "trigraph ??%c converted to %c",
				       note->type,
				       (int) _cpp_trigraph_map[note->type]);
	      else
		{
		  cpp_warning_with_line 
		    (pfile, CPP_W_TRIGRAPHS,
                     pfile->line_table->highest_line, col,
		     "trigraph ??%c ignored, use -trigraphs to enable",
		     note->type);
		}
	    }
	}
      else if (note->type == 0)
	/* Already processed in lex_raw_string.  */;
      else
	abort ();
    }
}

/* Skip a C-style block comment.  We find the end of the comment by
   seeing if an asterisk is before every '/' we encounter.  Returns
   nonzero if comment terminated by EOF, zero otherwise.

   Buffer->cur points to the initial asterisk of the comment.  */
bool
_cpp_skip_block_comment (cpp_reader *pfile)
{
  cpp_buffer *buffer = pfile->buffer;
  const uchar *cur = buffer->cur;
  uchar c;

  cur++;
  if (*cur == '/')
    cur++;

  for (;;)
    {
      /* People like decorating comments with '*', so check for '/'
	 instead for efficiency.  */
      c = *cur++;

      if (c == '/')
	{
	  if (cur[-2] == '*')
	    break;

	  /* Warn about potential nested comments, but not if the '/'
	     comes immediately before the true comment delimiter.
	     Don't bother to get it right across escaped newlines.  */
	  if (CPP_OPTION (pfile, warn_comments)
	      && cur[0] == '*' && cur[1] != '/')
	    {
	      buffer->cur = cur;
	      cpp_warning_with_line (pfile, CPP_W_COMMENTS,
				     pfile->line_table->highest_line,
				     CPP_BUF_COL (buffer),
				     "\"/*\" within comment");
	    }
	}
      else if (c == '\n')
	{
	  unsigned int cols;
	  buffer->cur = cur - 1;
	  _cpp_process_line_notes (pfile, true);
	  if (buffer->next_line >= buffer->rlimit)
	    return true;
	  _cpp_clean_line (pfile);

	  cols = buffer->next_line - buffer->line_base;
	  CPP_INCREMENT_LINE (pfile, cols);

	  cur = buffer->cur;
	}
    }

  buffer->cur = cur;
  _cpp_process_line_notes (pfile, true);
  return false;
}

/* Skip a C++ line comment, leaving buffer->cur pointing to the
   terminating newline.  Handles escaped newlines.  Returns nonzero
   if a multiline comment.  */
static int
skip_line_comment (cpp_reader *pfile)
{
  cpp_buffer *buffer = pfile->buffer;
  location_t orig_line = pfile->line_table->highest_line;

  while (*buffer->cur != '\n')
    buffer->cur++;

  _cpp_process_line_notes (pfile, true);
  return orig_line != pfile->line_table->highest_line;
}

/* Skips whitespace, saving the next non-whitespace character.  */
static void
skip_whitespace (cpp_reader *pfile, cppchar_t c)
{
  cpp_buffer *buffer = pfile->buffer;
  bool saw_NUL = false;

  do
    {
      /* Horizontal space always OK.  */
      if (c == ' ' || c == '\t')
	;
      /* Just \f \v or \0 left.  */
      else if (c == '\0')
	saw_NUL = true;
      else if (pfile->state.in_directive && CPP_PEDANTIC (pfile))
	cpp_error_with_line (pfile, CPP_DL_PEDWARN, pfile->line_table->highest_line,
			     CPP_BUF_COL (buffer),
			     "%s in preprocessing directive",
			     c == '\f' ? "form feed" : "vertical tab");

      c = *buffer->cur++;
    }
  /* We only want non-vertical space, i.e. ' ' \t \f \v \0.  */
  while (is_nvspace (c));

  if (saw_NUL)
    cpp_error (pfile, CPP_DL_WARNING, "null character(s) ignored");

  buffer->cur--;
}

/* See if the characters of a number token are valid in a name (no
   '.', '+' or '-').  */
static int
name_p (cpp_reader *pfile, const cpp_string *string)
{
  unsigned int i;

  for (i = 0; i < string->len; i++)
    if (!is_idchar (string->text[i]))
      return 0;

  return 1;
}

/* After parsing an identifier or other sequence, produce a warning about
   sequences not in NFC/NFKC.  */
static void
warn_about_normalization (cpp_reader *pfile, 
			  const cpp_token *token,
			  const struct normalize_state *s)
{
  if (CPP_OPTION (pfile, warn_normalize) < NORMALIZE_STATE_RESULT (s)
      && !pfile->state.skipping)
    {
      /* Make sure that the token is printed using UCNs, even
	 if we'd otherwise happily print UTF-8.  */
      unsigned char *buf = XNEWVEC (unsigned char, cpp_token_len (token));
      size_t sz;

      sz = cpp_spell_token (pfile, token, buf, false) - buf;
      if (NORMALIZE_STATE_RESULT (s) == normalized_C)
	cpp_warning_with_line (pfile, CPP_W_NORMALIZE, token->src_loc, 0,
			       "`%.*s' is not in NFKC", (int) sz, buf);
      else
	cpp_warning_with_line (pfile, CPP_W_NORMALIZE, token->src_loc, 0,
			       "`%.*s' is not in NFC", (int) sz, buf);
      free (buf);
    }
}

static const cppchar_t utf8_signifier = 0xC0;

/* Returns TRUE if the sequence starting at buffer->cur is valid in
   an identifier.  FIRST is TRUE if this starts an identifier.  */
static bool
forms_identifier_p (cpp_reader *pfile, int first,
		    struct normalize_state *state)
{
  cpp_buffer *buffer = pfile->buffer;

  if (*buffer->cur == '$')
    {
      if (!CPP_OPTION (pfile, dollars_in_ident))
	return false;

      buffer->cur++;
      if (CPP_OPTION (pfile, warn_dollars) && !pfile->state.skipping)
	{
	  CPP_OPTION (pfile, warn_dollars) = 0;
	  cpp_error (pfile, CPP_DL_PEDWARN, "'$' in identifier or number");
	}

      return true;
    }

  /* Is this a syntactically valid UCN or a valid UTF-8 char?  */
  if (CPP_OPTION (pfile, extended_identifiers))
    {
      cppchar_t s;
      if (*buffer->cur >= utf8_signifier)
	{
	  if (_cpp_valid_utf8 (pfile, &buffer->cur, buffer->rlimit, 1 + !first,
			       state, &s))
	    return true;
	}
      else if (*buffer->cur == '\\'
	       && (buffer->cur[1] == 'u' || buffer->cur[1] == 'U'))
	{
	  buffer->cur += 2;
	  if (_cpp_valid_ucn (pfile, &buffer->cur, buffer->rlimit, 1 + !first,
			      state, &s, NULL, NULL))
	    return true;
	  buffer->cur -= 2;
	}
    }

  return false;
}

/* Helper function to issue error about improper __VA_OPT__ use.  */
static void
maybe_va_opt_error (cpp_reader *pfile)
{
  if (CPP_PEDANTIC (pfile) && !CPP_OPTION (pfile, va_opt))
    {
      /* __VA_OPT__ should not be accepted at all, but allow it in
	 system headers.  */
      if (!cpp_in_system_header (pfile))
	cpp_error (pfile, CPP_DL_PEDWARN,
		   "__VA_OPT__ is not available until C++2a");
    }
  else if (!pfile->state.va_args_ok)
    {
      /* __VA_OPT__ should only appear in the replacement list of a
	 variadic macro.  */
      cpp_error (pfile, CPP_DL_PEDWARN,
		 "__VA_OPT__ can only appear in the expansion"
		 " of a C++2a variadic macro");
    }
}

/* Helper function to get the cpp_hashnode of the identifier BASE.  */
static cpp_hashnode *
lex_identifier_intern (cpp_reader *pfile, const uchar *base)
{
  cpp_hashnode *result;
  const uchar *cur;
  unsigned int len;
  unsigned int hash = HT_HASHSTEP (0, *base);

  cur = base + 1;
  while (ISIDNUM (*cur))
    {
      hash = HT_HASHSTEP (hash, *cur);
      cur++;
    }
  len = cur - base;
  hash = HT_HASHFINISH (hash, len);
  result = CPP_HASHNODE (ht_lookup_with_hash (pfile->hash_table,
					      base, len, hash, HT_ALLOC));

  /* Rarely, identifiers require diagnostics when lexed.  */
  if (__builtin_expect ((result->flags & NODE_DIAGNOSTIC)
			&& !pfile->state.skipping, 0))
    {
      /* It is allowed to poison the same identifier twice.  */
      if ((result->flags & NODE_POISONED) && !pfile->state.poisoned_ok)
	cpp_error (pfile, CPP_DL_ERROR, "attempt to use poisoned \"%s\"",
		   NODE_NAME (result));

      /* Constraint 6.10.3.5: __VA_ARGS__ should only appear in the
	 replacement list of a variadic macro.  */
      if (result == pfile->spec_nodes.n__VA_ARGS__
	  && !pfile->state.va_args_ok)
	{
	  if (CPP_OPTION (pfile, cplusplus))
	    cpp_error (pfile, CPP_DL_PEDWARN,
		       "__VA_ARGS__ can only appear in the expansion"
		       " of a C++11 variadic macro");
	  else
	    cpp_error (pfile, CPP_DL_PEDWARN,
		       "__VA_ARGS__ can only appear in the expansion"
		       " of a C99 variadic macro");
	}

      if (result == pfile->spec_nodes.n__VA_OPT__)
	maybe_va_opt_error (pfile);

      /* For -Wc++-compat, warn about use of C++ named operators.  */
      if (result->flags & NODE_WARN_OPERATOR)
	cpp_warning (pfile, CPP_W_CXX_OPERATOR_NAMES,
		     "identifier \"%s\" is a special operator name in C++",
		     NODE_NAME (result));
    }

  return result;
}

/* Get the cpp_hashnode of an identifier specified by NAME in
   the current cpp_reader object.  If none is found, NULL is returned.  */
cpp_hashnode *
_cpp_lex_identifier (cpp_reader *pfile, const char *name)
{
  cpp_hashnode *result;
  result = lex_identifier_intern (pfile, (uchar *) name);
  return result;
}

/* Lex an identifier starting at BUFFER->CUR - 1.  */
static cpp_hashnode *
lex_identifier (cpp_reader *pfile, const uchar *base, bool starts_ucn,
		struct normalize_state *nst, cpp_hashnode **spelling)
{
  cpp_hashnode *result;
  const uchar *cur;
  unsigned int len;
  unsigned int hash = HT_HASHSTEP (0, *base);

  cur = pfile->buffer->cur;
  if (! starts_ucn)
    {
      while (ISIDNUM (*cur))
	{
	  hash = HT_HASHSTEP (hash, *cur);
	  cur++;
	}
      NORMALIZE_STATE_UPDATE_IDNUM (nst, *(cur - 1));
    }
  pfile->buffer->cur = cur;
  if (starts_ucn || forms_identifier_p (pfile, false, nst))
    {
      /* Slower version for identifiers containing UCNs
	 or extended chars (including $).  */
      do {
	while (ISIDNUM (*pfile->buffer->cur))
	  {
	    NORMALIZE_STATE_UPDATE_IDNUM (nst, *pfile->buffer->cur);
	    pfile->buffer->cur++;
	  }
      } while (forms_identifier_p (pfile, false, nst));
      result = _cpp_interpret_identifier (pfile, base,
					  pfile->buffer->cur - base);
      *spelling = cpp_lookup (pfile, base, pfile->buffer->cur - base);
    }
  else
    {
      len = cur - base;
      hash = HT_HASHFINISH (hash, len);

      result = CPP_HASHNODE (ht_lookup_with_hash (pfile->hash_table,
						  base, len, hash, HT_ALLOC));
      *spelling = result;
    }

  /* Rarely, identifiers require diagnostics when lexed.  */
  if (__builtin_expect ((result->flags & NODE_DIAGNOSTIC)
			&& !pfile->state.skipping, 0))
    {
      /* It is allowed to poison the same identifier twice.  */
      if ((result->flags & NODE_POISONED) && !pfile->state.poisoned_ok)
	cpp_error (pfile, CPP_DL_ERROR, "attempt to use poisoned \"%s\"",
		   NODE_NAME (result));

      /* Constraint 6.10.3.5: __VA_ARGS__ should only appear in the
	 replacement list of a variadic macro.  */
      if (result == pfile->spec_nodes.n__VA_ARGS__
	  && !pfile->state.va_args_ok)
	{
	  if (CPP_OPTION (pfile, cplusplus))
	    cpp_error (pfile, CPP_DL_PEDWARN,
		       "__VA_ARGS__ can only appear in the expansion"
		       " of a C++11 variadic macro");
	  else
	    cpp_error (pfile, CPP_DL_PEDWARN,
		       "__VA_ARGS__ can only appear in the expansion"
		       " of a C99 variadic macro");
	}

      /* __VA_OPT__ should only appear in the replacement list of a
	 variadic macro.  */
      if (result == pfile->spec_nodes.n__VA_OPT__)
	maybe_va_opt_error (pfile);

      /* For -Wc++-compat, warn about use of C++ named operators.  */
      if (result->flags & NODE_WARN_OPERATOR)
	cpp_warning (pfile, CPP_W_CXX_OPERATOR_NAMES,
		     "identifier \"%s\" is a special operator name in C++",
		     NODE_NAME (result));
    }

  return result;
}

/* Lex a number to NUMBER starting at BUFFER->CUR - 1.  */
static void
lex_number (cpp_reader *pfile, cpp_string *number,
	    struct normalize_state *nst)
{
  const uchar *cur;
  const uchar *base;
  uchar *dest;

  base = pfile->buffer->cur - 1;
  do
    {
      cur = pfile->buffer->cur;

      /* N.B. ISIDNUM does not include $.  */
      while (ISIDNUM (*cur) || *cur == '.' || DIGIT_SEP (*cur)
	     || VALID_SIGN (*cur, cur[-1]))
	{
	  NORMALIZE_STATE_UPDATE_IDNUM (nst, *cur);
	  cur++;
	}
      /* A number can't end with a digit separator.  */
      while (cur > pfile->buffer->cur && DIGIT_SEP (cur[-1]))
	--cur;

      pfile->buffer->cur = cur;
    }
  while (forms_identifier_p (pfile, false, nst));

  number->len = cur - base;
  dest = _cpp_unaligned_alloc (pfile, number->len + 1);
  memcpy (dest, base, number->len);
  dest[number->len] = '\0';
  number->text = dest;
}

/* Create a token of type TYPE with a literal spelling.  */
static void
create_literal (cpp_reader *pfile, cpp_token *token, const uchar *base,
		unsigned int len, enum cpp_ttype type)
{
  uchar *dest = _cpp_unaligned_alloc (pfile, len + 1);

  memcpy (dest, base, len);
  dest[len] = '\0';
  token->type = type;
  token->val.str.len = len;
  token->val.str.text = dest;
}

/* Subroutine of lex_raw_string: Append LEN chars from BASE to the buffer
   sequence from *FIRST_BUFF_P to LAST_BUFF_P.  */

static void
bufring_append (cpp_reader *pfile, const uchar *base, size_t len,
		_cpp_buff **first_buff_p, _cpp_buff **last_buff_p)
{
  _cpp_buff *first_buff = *first_buff_p;
  _cpp_buff *last_buff = *last_buff_p;

  if (first_buff == NULL)
    first_buff = last_buff = _cpp_get_buff (pfile, len);
  else if (len > BUFF_ROOM (last_buff))
    {
      size_t room = BUFF_ROOM (last_buff);
      memcpy (BUFF_FRONT (last_buff), base, room);
      BUFF_FRONT (last_buff) += room;
      base += room;
      len -= room;
      last_buff = _cpp_append_extend_buff (pfile, last_buff, len);
    }

  memcpy (BUFF_FRONT (last_buff), base, len);
  BUFF_FRONT (last_buff) += len;

  *first_buff_p = first_buff;
  *last_buff_p = last_buff;
}


/* Returns true if a macro has been defined.
   This might not work if compile with -save-temps,
   or preprocess separately from compilation.  */

static bool
is_macro(cpp_reader *pfile, const uchar *base)
{
  const uchar *cur = base;
  if (! ISIDST (*cur))
    return false;
  unsigned int hash = HT_HASHSTEP (0, *cur);
  ++cur;
  while (ISIDNUM (*cur))
    {
      hash = HT_HASHSTEP (hash, *cur);
      ++cur;
    }
  hash = HT_HASHFINISH (hash, cur - base);

  cpp_hashnode *result = CPP_HASHNODE (ht_lookup_with_hash (pfile->hash_table,
					base, cur - base, hash, HT_NO_INSERT));

  return result && cpp_macro_p (result);
}

/* Returns true if a literal suffix does not have the expected form
   and is defined as a macro.  */

static bool
is_macro_not_literal_suffix(cpp_reader *pfile, const uchar *base)
{
  /* User-defined literals outside of namespace std must start with a single
     underscore, so assume anything of that form really is a UDL suffix.
     We don't need to worry about UDLs defined inside namespace std because
     their names are reserved, so cannot be used as macro names in valid
     programs.  */
  if (base[0] == '_' && base[1] != '_')
    return false;
  return is_macro (pfile, base);
}

/* Lexes a raw string.  The stored string contains the spelling, including
   double quotes, delimiter string, '(' and ')', any leading
   'L', 'u', 'U' or 'u8' and 'R' modifier.  It returns the type of the
   literal, or CPP_OTHER if it was not properly terminated.

   The spelling is NUL-terminated, but it is not guaranteed that this
   is the first NUL since embedded NULs are preserved.  */

static void
lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base,
		const uchar *cur)
{
  uchar raw_prefix[17];
  uchar temp_buffer[18];
  const uchar *orig_base;
  unsigned int raw_prefix_len = 0, raw_suffix_len = 0;
  enum raw_str_phase { RAW_STR_PREFIX, RAW_STR, RAW_STR_SUFFIX };
  raw_str_phase phase = RAW_STR_PREFIX;
  enum cpp_ttype type;
  size_t total_len = 0;
  /* Index into temp_buffer during phases other than RAW_STR,
     during RAW_STR phase 17 to tell BUF_APPEND that nothing should
     be appended to temp_buffer.  */
  size_t temp_buffer_len = 0;
  _cpp_buff *first_buff = NULL, *last_buff = NULL;
  size_t raw_prefix_start;
  _cpp_line_note *note = &pfile->buffer->notes[pfile->buffer->cur_note];

  type = (*base == 'L' ? CPP_WSTRING :
	  *base == 'U' ? CPP_STRING32 :
	  *base == 'u' ? (base[1] == '8' ? CPP_UTF8STRING : CPP_STRING16)
	  : CPP_STRING);

#define BUF_APPEND(STR,LEN)					\
      do {							\
	bufring_append (pfile, (const uchar *)(STR), (LEN),	\
			&first_buff, &last_buff);		\
	total_len += (LEN);					\
	if (__builtin_expect (temp_buffer_len < 17, 0)		\
	    && (const uchar *)(STR) != base			\
	    && (LEN) <= 2)					\
	  {							\
	    memcpy (temp_buffer + temp_buffer_len,		\
		    (const uchar *)(STR), (LEN));		\
	    temp_buffer_len += (LEN);				\
	  }							\
      } while (0)

  orig_base = base;
  ++cur;
  raw_prefix_start = cur - base;
  for (;;)
    {
      cppchar_t c;

      /* If we previously performed any trigraph or line splicing
	 transformations, undo them in between the opening and closing
	 double quote.  */
      while (note->pos < cur)
	++note;
      for (; note->pos == cur; ++note)
	{
	  switch (note->type)
	    {
	    case '\\':
	    case ' ':
	      /* Restore backslash followed by newline.  */
	      BUF_APPEND (base, cur - base);
	      base = cur;
	      BUF_APPEND ("\\", 1);
	    after_backslash:
	      if (note->type == ' ')
		{
		  /* GNU backslash whitespace newline extension.  FIXME
		     could be any sequence of non-vertical space.  When we
		     can properly restore any such sequence, we should mark
		     this note as handled so _cpp_process_line_notes
		     doesn't warn.  */
		  BUF_APPEND (" ", 1);
		}

	      BUF_APPEND ("\n", 1);
	      break;

	    case 0:
	      /* Already handled.  */
	      break;

	    default:
	      if (_cpp_trigraph_map[note->type])
		{
		  /* Don't warn about this trigraph in
		     _cpp_process_line_notes, since trigraphs show up as
		     trigraphs in raw strings.  */
		  uchar type = note->type;
		  note->type = 0;

		  if (!CPP_OPTION (pfile, trigraphs))
		    /* If we didn't convert the trigraph in the first
		       place, don't do anything now either.  */
		    break;

		  BUF_APPEND (base, cur - base);
		  base = cur;
		  BUF_APPEND ("??", 2);

		  /* ??/ followed by newline gets two line notes, one for
		     the trigraph and one for the backslash/newline.  */
		  if (type == '/' && note[1].pos == cur)
		    {
		      if (note[1].type != '\\'
			  && note[1].type != ' ')
			abort ();
		      BUF_APPEND ("/", 1);
		      ++note;
		      goto after_backslash;
		    }
		  else
		    {
		      /* Skip the replacement character.  */
		      base = ++cur;
		      BUF_APPEND (&type, 1);
		      c = type;
		      goto check_c;
		    }
		}
	      else
		abort ();
	      break;
	    }
	}
      c = *cur++;
      if (__builtin_expect (temp_buffer_len < 17, 0))
	temp_buffer[temp_buffer_len++] = c;

     check_c:
      if (phase == RAW_STR_PREFIX)
	{
	  while (raw_prefix_len < temp_buffer_len)
	    {
	      raw_prefix[raw_prefix_len] = temp_buffer[raw_prefix_len];
	      switch (raw_prefix[raw_prefix_len])
		{
		case ' ': case '(': case ')': case '\\': case '\t':
		case '\v': case '\f': case '\n': default:
		  break;
		/* Basic source charset except the above chars.  */
		case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
		case 'g': case 'h': case 'i': case 'j': case 'k': case 'l':
		case 'm': case 'n': case 'o': case 'p': case 'q': case 'r':
		case 's': case 't': case 'u': case 'v': case 'w': case 'x':
		case 'y': case 'z':
		case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
		case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
		case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
		case 'S': case 'T': case 'U': case 'V': case 'W': case 'X':
		case 'Y': case 'Z':
		case '0': case '1': case '2': case '3': case '4': case '5':
		case '6': case '7': case '8': case '9':
		case '_': case '{': case '}': case '#': case '[': case ']':
		case '<': case '>': case '%': case ':': case ';': case '.':
		case '?': case '*': case '+': case '-': case '/': case '^':
		case '&': case '|': case '~': case '!': case '=': case ',':
		case '"': case '\'':
		  if (raw_prefix_len < 16)
		    {
		      raw_prefix_len++;
		      continue;
		    }
		  break;
		}

	      if (raw_prefix[raw_prefix_len] != '(')
		{
		  int col = CPP_BUF_COLUMN (pfile->buffer, cur) + 1;
		  if (raw_prefix_len == 16)
		    cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc,
					 col, "raw string delimiter longer "
					      "than 16 characters");
		  else if (raw_prefix[raw_prefix_len] == '\n')
		    cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc,
					 col, "invalid new-line in raw "
					      "string delimiter");
		  else
		    cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc,
					 col, "invalid character '%c' in "
					      "raw string delimiter",
					 (int) raw_prefix[raw_prefix_len]);
		  pfile->buffer->cur = orig_base + raw_prefix_start - 1;
		  create_literal (pfile, token, orig_base,
				  raw_prefix_start - 1, CPP_OTHER);
		  if (first_buff)
		    _cpp_release_buff (pfile, first_buff);
		  return;
		}
	      raw_prefix[raw_prefix_len] = '"';
	      phase = RAW_STR;
	      /* Nothing should be appended to temp_buffer during
		 RAW_STR phase.  */
	      temp_buffer_len = 17;
	      break;
	    }
	  continue;
	}
      else if (phase == RAW_STR_SUFFIX)
	{
	  while (raw_suffix_len <= raw_prefix_len
		 && raw_suffix_len < temp_buffer_len
		 && temp_buffer[raw_suffix_len] == raw_prefix[raw_suffix_len])
	    raw_suffix_len++;
	  if (raw_suffix_len > raw_prefix_len)
	    break;
	  if (raw_suffix_len == temp_buffer_len)
	    continue;
	  phase = RAW_STR;
	  /* Nothing should be appended to temp_buffer during
	     RAW_STR phase.  */
	  temp_buffer_len = 17;
	}
      if (c == ')')
	{
	  phase = RAW_STR_SUFFIX;
	  raw_suffix_len = 0;
	  temp_buffer_len = 0;
	}
      else if (c == '\n')
	{
	  if (pfile->state.in_directive
	      || (pfile->state.parsing_args
		  && pfile->buffer->next_line >= pfile->buffer->rlimit))
	    {
	      cur--;
	      type = CPP_OTHER;
	      cpp_error_with_line (pfile, CPP_DL_ERROR, token->src_loc, 0,
				   "unterminated raw string");
	      break;
	    }

	  BUF_APPEND (base, cur - base);

	  if (pfile->buffer->cur < pfile->buffer->rlimit)
	    CPP_INCREMENT_LINE (pfile, 0);
	  pfile->buffer->need_line = true;

	  pfile->buffer->cur = cur-1;
	  _cpp_process_line_notes (pfile, false);
	  if (!_cpp_get_fresh_line (pfile))
	    {
	      location_t src_loc = token->src_loc;
	      token->type = CPP_EOF;
	      /* Tell the compiler the line number of the EOF token.  */
	      token->src_loc = pfile->line_table->highest_line;
	      token->flags = BOL;
	      if (first_buff != NULL)
		_cpp_release_buff (pfile, first_buff);
	      cpp_error_with_line (pfile, CPP_DL_ERROR, src_loc, 0,
				   "unterminated raw string");
	      return;
	    }

	  cur = base = pfile->buffer->cur;
	  note = &pfile->buffer->notes[pfile->buffer->cur_note];
	}
    }

  if (CPP_OPTION (pfile, user_literals))
    {
      /* If a string format macro, say from inttypes.h, is placed touching
	 a string literal it could be parsed as a C++11 user-defined string
	 literal thus breaking the program.  */
      if (is_macro_not_literal_suffix (pfile, cur))
	{
	  /* Raise a warning, but do not consume subsequent tokens.  */
	  if (CPP_OPTION (pfile, warn_literal_suffix) && !pfile->state.skipping)
	    cpp_warning_with_line (pfile, CPP_W_LITERAL_SUFFIX,
				   token->src_loc, 0,
				   "invalid suffix on literal; C++11 requires "
				   "a space between literal and string macro");
	}
      /* Grab user defined literal suffix.  */
      else if (ISIDST (*cur))
	{
	  type = cpp_userdef_string_add_type (type);
	  ++cur;

	  while (ISIDNUM (*cur))
	    ++cur;
	}
    }

  pfile->buffer->cur = cur;
  if (first_buff == NULL)
    create_literal (pfile, token, base, cur - base, type);
  else
    {
      uchar *dest = _cpp_unaligned_alloc (pfile, total_len + (cur - base) + 1);

      token->type = type;
      token->val.str.len = total_len + (cur - base);
      token->val.str.text = dest;
      last_buff = first_buff;
      while (last_buff != NULL)
	{
	  memcpy (dest, last_buff->base,
		  BUFF_FRONT (last_buff) - last_buff->base);
	  dest += BUFF_FRONT (last_buff) - last_buff->base;
	  last_buff = last_buff->next;
	}
      _cpp_release_buff (pfile, first_buff);
      memcpy (dest, base, cur - base);
      dest[cur - base] = '\0';
    }
}

/* Lexes a string, character constant, or angle-bracketed header file
   name.  The stored string contains the spelling, including opening
   quote and any leading 'L', 'u', 'U' or 'u8' and optional
   'R' modifier.  It returns the type of the literal, or CPP_OTHER
   if it was not properly terminated, or CPP_LESS for an unterminated
   header name which must be relexed as normal tokens.

   The spelling is NUL-terminated, but it is not guaranteed that this
   is the first NUL since embedded NULs are preserved.  */
static void
lex_string (cpp_reader *pfile, cpp_token *token, const uchar *base)
{
  bool saw_NUL = false;
  const uchar *cur;
  cppchar_t terminator;
  enum cpp_ttype type;

  cur = base;
  terminator = *cur++;
  if (terminator == 'L' || terminator == 'U')
    terminator = *cur++;
  else if (terminator == 'u')
    {
      terminator = *cur++;
      if (terminator == '8')
	terminator = *cur++;
    }
  if (terminator == 'R')
    {
      lex_raw_string (pfile, token, base, cur);
      return;
    }
  if (terminator == '"')
    type = (*base == 'L' ? CPP_WSTRING :
	    *base == 'U' ? CPP_STRING32 :
	    *base == 'u' ? (base[1] == '8' ? CPP_UTF8STRING : CPP_STRING16)
			 : CPP_STRING);
  else if (terminator == '\'')
    type = (*base == 'L' ? CPP_WCHAR :
	    *base == 'U' ? CPP_CHAR32 :
	    *base == 'u' ? (base[1] == '8' ? CPP_UTF8CHAR : CPP_CHAR16)
			 : CPP_CHAR);
  else
    terminator = '>', type = CPP_HEADER_NAME;

  for (;;)
    {
      cppchar_t c = *cur++;

      /* In #include-style directives, terminators are not escapable.  */
      if (c == '\\' && !pfile->state.angled_headers && *cur != '\n')
	cur++;
      else if (c == terminator)
	break;
      else if (c == '\n')
	{
	  cur--;
	  /* Unmatched quotes always yield undefined behavior, but
	     greedy lexing means that what appears to be an unterminated
	     header name may actually be a legitimate sequence of tokens.  */
	  if (terminator == '>')
	    {
	      token->type = CPP_LESS;
	      return;
	    }
	  type = CPP_OTHER;
	  break;
	}
      else if (c == '\0')
	saw_NUL = true;
    }

  if (saw_NUL && !pfile->state.skipping)
    cpp_error (pfile, CPP_DL_WARNING,
	       "null character(s) preserved in literal");

  if (type == CPP_OTHER && CPP_OPTION (pfile, lang) != CLK_ASM)
    cpp_error (pfile, CPP_DL_PEDWARN, "missing terminating %c character",
	       (int) terminator);

  if (CPP_OPTION (pfile, user_literals))
    {
      /* If a string format macro, say from inttypes.h, is placed touching
	 a string literal it could be parsed as a C++11 user-defined string
	 literal thus breaking the program.  */
      if (is_macro_not_literal_suffix (pfile, cur))
	{
	  /* Raise a warning, but do not consume subsequent tokens.  */
	  if (CPP_OPTION (pfile, warn_literal_suffix) && !pfile->state.skipping)
	    cpp_warning_with_line (pfile, CPP_W_LITERAL_SUFFIX,
				   token->src_loc, 0,
				   "invalid suffix on literal; C++11 requires "
				   "a space between literal and string macro");
	}
      /* Grab user defined literal suffix.  */
      else if (ISIDST (*cur))
	{
	  type = cpp_userdef_char_add_type (type);
	  type = cpp_userdef_string_add_type (type);
          ++cur;

	  while (ISIDNUM (*cur))
	    ++cur;
	}
    }
  else if (CPP_OPTION (pfile, cpp_warn_cxx11_compat)
	   && is_macro (pfile, cur)
	   && !pfile->state.skipping)
    cpp_warning_with_line (pfile, CPP_W_CXX11_COMPAT,
			   token->src_loc, 0, "C++11 requires a space "
			   "between string literal and macro");

  pfile->buffer->cur = cur;
  create_literal (pfile, token, base, cur - base, type);
}

/* Return the comment table. The client may not make any assumption
   about the ordering of the table.  */
cpp_comment_table *
cpp_get_comments (cpp_reader *pfile)
{
  return &pfile->comments;
}

/* Append a comment to the end of the comment table. */
static void 
store_comment (cpp_reader *pfile, cpp_token *token) 
{
  int len;

  if (pfile->comments.allocated == 0)
    {
      pfile->comments.allocated = 256; 
      pfile->comments.entries = (cpp_comment *) xmalloc
	(pfile->comments.allocated * sizeof (cpp_comment));
    }

  if (pfile->comments.count == pfile->comments.allocated)
    {
      pfile->comments.allocated *= 2;
      pfile->comments.entries = (cpp_comment *) xrealloc
	(pfile->comments.entries,
	 pfile->comments.allocated * sizeof (cpp_comment));
    }

  len = token->val.str.len;

  /* Copy comment. Note, token may not be NULL terminated. */
  pfile->comments.entries[pfile->comments.count].comment = 
    (char *) xmalloc (sizeof (char) * (len + 1));
  memcpy (pfile->comments.entries[pfile->comments.count].comment,
	  token->val.str.text, len);
  pfile->comments.entries[pfile->comments.count].comment[len] = '\0';

  /* Set source location. */
  pfile->comments.entries[pfile->comments.count].sloc = token->src_loc;

  /* Increment the count of entries in the comment table. */
  pfile->comments.count++;
}

/* The stored comment includes the comment start and any terminator.  */
static void
save_comment (cpp_reader *pfile, cpp_token *token, const unsigned char *from,
	      cppchar_t type)
{
  unsigned char *buffer;
  unsigned int len, clen, i;

  len = pfile->buffer->cur - from + 1; /* + 1 for the initial '/'.  */

  /* C++ comments probably (not definitely) have moved past a new
     line, which we don't want to save in the comment.  */
  if (is_vspace (pfile->buffer->cur[-1]))
    len--;

  /* If we are currently in a directive or in argument parsing, then
     we need to store all C++ comments as C comments internally, and
     so we need to allocate a little extra space in that case.

     Note that the only time we encounter a directive here is
     when we are saving comments in a "#define".  */
  clen = ((pfile->state.in_directive || pfile->state.parsing_args)
	  && type == '/') ? len + 2 : len;

  buffer = _cpp_unaligned_alloc (pfile, clen);

  token->type = CPP_COMMENT;
  token->val.str.len = clen;
  token->val.str.text = buffer;

  buffer[0] = '/';
  memcpy (buffer + 1, from, len - 1);

  /* Finish conversion to a C comment, if necessary.  */
  if ((pfile->state.in_directive || pfile->state.parsing_args) && type == '/')
    {
      buffer[1] = '*';
      buffer[clen - 2] = '*';
      buffer[clen - 1] = '/';
      /* As there can be in a C++ comments illegal sequences for C comments
         we need to filter them out.  */
      for (i = 2; i < (clen - 2); i++)
        if (buffer[i] == '/' && (buffer[i - 1] == '*' || buffer[i + 1] == '*'))
          buffer[i] = '|';
    }

  /* Finally store this comment for use by clients of libcpp. */
  store_comment (pfile, token);
}

/* Returns true if comment at COMMENT_START is a recognized FALLTHROUGH
   comment.  */

static bool
fallthrough_comment_p (cpp_reader *pfile, const unsigned char *comment_start)
{
  const unsigned char *from = comment_start + 1;

  switch (CPP_OPTION (pfile, cpp_warn_implicit_fallthrough))
    {
      /* For both -Wimplicit-fallthrough=0 and -Wimplicit-fallthrough=5 we
	 don't recognize any comments.  The latter only checks attributes,
	 the former doesn't warn.  */
    case 0:
    default:
      return false;
      /* -Wimplicit-fallthrough=1 considers any comment, no matter what
	 content it has.  */
    case 1:
      return true;
    case 2:
      /* -Wimplicit-fallthrough=2 looks for (case insensitive)
	 .*falls?[ \t-]*thr(u|ough).* regex.  */
      for (; (size_t) (pfile->buffer->cur - from) >= sizeof "fallthru" - 1;
	   from++)
	{
	  /* Is there anything like strpbrk with upper boundary, or
	     memchr looking for 2 characters rather than just one?  */
	  if (from[0] != 'f' && from[0] != 'F')
	    continue;
	  if (from[1] != 'a' && from[1] != 'A')
	    continue;
	  if (from[2] != 'l' && from[2] != 'L')
	    continue;
	  if (from[3] != 'l' && from[3] != 'L')
	    continue;
	  from += sizeof "fall" - 1;
	  if (from[0] == 's' || from[0] == 'S')
	    from++;
	  while (*from == ' ' || *from == '\t' || *from == '-')
	    from++;
	  if (from[0] != 't' && from[0] != 'T')
	    continue;
	  if (from[1] != 'h' && from[1] != 'H')
	    continue;
	  if (from[2] != 'r' && from[2] != 'R')
	    continue;
	  if (from[3] == 'u' || from[3] == 'U')
	    return true;
	  if (from[3] != 'o' && from[3] != 'O')
	    continue;
	  if (from[4] != 'u' && from[4] != 'U')
	    continue;
	  if (from[5] != 'g' && from[5] != 'G')
	    continue;
	  if (from[6] != 'h' && from[6] != 'H')
	    continue;
	  return true;
	}
      return false;
    case 3:
    case 4:
      break;
    }

  /* Whole comment contents:
     -fallthrough
     @fallthrough@
   */
  if (*from == '-' || *from == '@')
    {
      size_t len = sizeof "fallthrough" - 1;
      if ((size_t) (pfile->buffer->cur - from - 1) < len)
	return false;
      if (memcmp (from + 1, "fallthrough", len))
	return false;
      if (*from == '@')
	{
	  if (from[len + 1] != '@')
	    return false;
	  len++;
	}
      from += 1 + len;
    }
  /* Whole comment contents (regex):
     lint -fallthrough[ \t]*
   */
  else if (*from == 'l')
    {
      size_t len = sizeof "int -fallthrough" - 1;
      if ((size_t) (pfile->buffer->cur - from - 1) < len)
	return false;
      if (memcmp (from + 1, "int -fallthrough", len))
	return false;
      from += 1 + len;
      while (*from == ' ' || *from == '\t')
	from++;
    }
  /* Whole comment contents (regex):
     [ \t]*FALLTHR(U|OUGH)[ \t]*
   */
  else if (CPP_OPTION (pfile, cpp_warn_implicit_fallthrough) == 4)
    {
      while (*from == ' ' || *from == '\t')
	from++;
      if ((size_t) (pfile->buffer->cur - from)  < sizeof "FALLTHRU" - 1)
	return false;
      if (memcmp (from, "FALLTHR", sizeof "FALLTHR" - 1))
	return false;
      from += sizeof "FALLTHR" - 1;
      if (*from == 'U')
	from++;
      else if ((size_t) (pfile->buffer->cur - from)  < sizeof "OUGH" - 1)
	return false;
      else if (memcmp (from, "OUGH", sizeof "OUGH" - 1))
	return false;
      else
	from += sizeof "OUGH" - 1;
      while (*from == ' ' || *from == '\t')
	from++;
    }
  /* Whole comment contents (regex):
     [ \t.!]*(ELSE,? |INTENTIONAL(LY)? )?FALL(S | |-)?THR(OUGH|U)[ \t.!]*(-[^\n\r]*)?
     [ \t.!]*(Else,? |Intentional(ly)? )?Fall((s | |-)[Tt]|t)hr(ough|u)[ \t.!]*(-[^\n\r]*)?
     [ \t.!]*([Ee]lse,? |[Ii]ntentional(ly)? )?fall(s | |-)?thr(ough|u)[ \t.!]*(-[^\n\r]*)?
   */
  else
    {
      while (*from == ' ' || *from == '\t' || *from == '.' || *from == '!')
	from++;
      unsigned char f = *from;
      bool all_upper = false;
      if (f == 'E' || f == 'e')
	{
	  if ((size_t) (pfile->buffer->cur - from)
	      < sizeof "else fallthru" - 1)
	    return false;
	  if (f == 'E' && memcmp (from + 1, "LSE", sizeof "LSE" - 1) == 0)
	    all_upper = true;
	  else if (memcmp (from + 1, "lse", sizeof "lse" - 1))
	    return false;
	  from += sizeof "else" - 1;
	  if (*from == ',')
	    from++;
	  if (*from != ' ')
	    return false;
	  from++;
	  if (all_upper && *from == 'f')
	    return false;
	  if (f == 'e' && *from == 'F')
	    return false;
	  f = *from;
	}
      else if (f == 'I' || f == 'i')
	{
	  if ((size_t) (pfile->buffer->cur - from)
	      < sizeof "intentional fallthru" - 1)
	    return false;
	  if (f == 'I' && memcmp (from + 1, "NTENTIONAL",
				  sizeof "NTENTIONAL" - 1) == 0)
	    all_upper = true;
	  else if (memcmp (from + 1, "ntentional",
			   sizeof "ntentional" - 1))
	    return false;
	  from += sizeof "intentional" - 1;
	  if (*from == ' ')
	    {
	      from++;
	      if (all_upper && *from == 'f')
		return false;
	    }
	  else if (all_upper)
	    {
	      if (memcmp (from, "LY F", sizeof "LY F" - 1))
		return false;
	      from += sizeof "LY " - 1;
	    }
	  else
	    {
	      if (memcmp (from, "ly ", sizeof "ly " - 1))
		return false;
	      from += sizeof "ly " - 1;
	    }
	  if (f == 'i' && *from == 'F')
	    return false;
	  f = *from;
	}
      if (f != 'F' && f != 'f')
	return false;
      if ((size_t) (pfile->buffer->cur - from) < sizeof "fallthru" - 1)
	return false;
      if (f == 'F' && memcmp (from + 1, "ALL", sizeof "ALL" - 1) == 0)
	all_upper = true;
      else if (all_upper)
	return false;
      else if (memcmp (from + 1, "all", sizeof "all" - 1))
	return false;
      from += sizeof "fall" - 1;
      if (*from == (all_upper ? 'S' : 's') && from[1] == ' ')
	from += 2;
      else if (*from == ' ' || *from == '-')
	from++;
      else if (*from != (all_upper ? 'T' : 't'))
	return false;
      if ((f == 'f' || *from != 'T') && (all_upper || *from != 't'))
	return false;
      if ((size_t) (pfile->buffer->cur - from) < sizeof "thru" - 1)
	return false;
      if (memcmp (from + 1, all_upper ? "HRU" : "hru", sizeof "hru" - 1))
	{
	  if ((size_t) (pfile->buffer->cur - from) < sizeof "through" - 1)
	    return false;
	  if (memcmp (from + 1, all_upper ? "HROUGH" : "hrough",
		      sizeof "hrough" - 1))
	    return false;
	  from += sizeof "through" - 1;
	}
      else
	from += sizeof "thru" - 1;
      while (*from == ' ' || *from == '\t' || *from == '.' || *from == '!')
	from++;
      if (*from == '-')
	{
	  from++;
	  if (*comment_start == '*')
	    {
	      do
		{
		  while (*from && *from != '*'
			 && *from != '\n' && *from != '\r')
		    from++;
		  if (*from != '*' || from[1] == '/')
		    break;
		  from++;
		}
	      while (1);
	    }
	  else
	    while (*from && *from != '\n' && *from != '\r')
	      from++;
	}
    }
  /* C block comment.  */
  if (*comment_start == '*')
    {
      if (*from != '*' || from[1] != '/')
	return false;
    }
  /* C++ line comment.  */
  else if (*from != '\n')
    return false;

  return true;
}

/* Allocate COUNT tokens for RUN.  */
void
_cpp_init_tokenrun (tokenrun *run, unsigned int count)
{
  run->base = XNEWVEC (cpp_token, count);
  run->limit = run->base + count;
  run->next = NULL;
}

/* Returns the next tokenrun, or creates one if there is none.  */
static tokenrun *
next_tokenrun (tokenrun *run)
{
  if (run->next == NULL)
    {
      run->next = XNEW (tokenrun);
      run->next->prev = run;
      _cpp_init_tokenrun (run->next, 250);
    }

  return run->next;
}

/* Return the number of not yet processed token in a given
   context.  */
int
_cpp_remaining_tokens_num_in_context (cpp_context *context)
{
  if (context->tokens_kind == TOKENS_KIND_DIRECT)
    return (LAST (context).token - FIRST (context).token);
  else if (context->tokens_kind == TOKENS_KIND_INDIRECT
	   || context->tokens_kind == TOKENS_KIND_EXTENDED)
    return (LAST (context).ptoken - FIRST (context).ptoken);
  else
      abort ();
}

/* Returns the token present at index INDEX in a given context.  If
   INDEX is zero, the next token to be processed is returned.  */
static const cpp_token*
_cpp_token_from_context_at (cpp_context *context, int index)
{
  if (context->tokens_kind == TOKENS_KIND_DIRECT)
    return &(FIRST (context).token[index]);
  else if (context->tokens_kind == TOKENS_KIND_INDIRECT
	   || context->tokens_kind == TOKENS_KIND_EXTENDED)
    return FIRST (context).ptoken[index];
 else
   abort ();
}

/* Look ahead in the input stream.  */
const cpp_token *
cpp_peek_token (cpp_reader *pfile, int index)
{
  cpp_context *context = pfile->context;
  const cpp_token *peektok;
  int count;

  /* First, scan through any pending cpp_context objects.  */
  while (context->prev)
    {
      ptrdiff_t sz = _cpp_remaining_tokens_num_in_context (context);

      if (index < (int) sz)
        return _cpp_token_from_context_at (context, index);
      index -= (int) sz;
      context = context->prev;
    }

  /* We will have to read some new tokens after all (and do so
     without invalidating preceding tokens).  */
  count = index;
  pfile->keep_tokens++;

  /* For peeked tokens temporarily disable line_change reporting,
     until the tokens are parsed for real.  */
  void (*line_change) (cpp_reader *, const cpp_token *, int)
    = pfile->cb.line_change;
  pfile->cb.line_change = NULL;

  do
    {
      peektok = _cpp_lex_token (pfile);
      if (peektok->type == CPP_EOF)
	{
	  index--;
	  break;
	}
    }
  while (index--);

  _cpp_backup_tokens_direct (pfile, count - index);
  pfile->keep_tokens--;
  pfile->cb.line_change = line_change;

  return peektok;
}

/* Allocate a single token that is invalidated at the same time as the
   rest of the tokens on the line.  Has its line and col set to the
   same as the last lexed token, so that diagnostics appear in the
   right place.  */
cpp_token *
_cpp_temp_token (cpp_reader *pfile)
{
  cpp_token *old, *result;
  ptrdiff_t sz = pfile->cur_run->limit - pfile->cur_token;
  ptrdiff_t la = (ptrdiff_t) pfile->lookaheads;

  old = pfile->cur_token - 1;
  /* Any pre-existing lookaheads must not be clobbered.  */
  if (la)
    {
      if (sz <= la)
        {
          tokenrun *next = next_tokenrun (pfile->cur_run);

          if (sz < la)
            memmove (next->base + 1, next->base,
                     (la - sz) * sizeof (cpp_token));

          next->base[0] = pfile->cur_run->limit[-1];
        }

      if (sz > 1)
        memmove (pfile->cur_token + 1, pfile->cur_token,
                 MIN (la, sz - 1) * sizeof (cpp_token));
    }

  if (!sz && pfile->cur_token == pfile->cur_run->limit)
    {
      pfile->cur_run = next_tokenrun (pfile->cur_run);
      pfile->cur_token = pfile->cur_run->base;
    }

  result = pfile->cur_token++;
  result->src_loc = old->src_loc;
  return result;
}

/* Lex a token into RESULT (external interface).  Takes care of issues
   like directive handling, token lookahead, multiple include
   optimization and skipping.  */
const cpp_token *
_cpp_lex_token (cpp_reader *pfile)
{
  cpp_token *result;

  for (;;)
    {
      if (pfile->cur_token == pfile->cur_run->limit)
	{
	  pfile->cur_run = next_tokenrun (pfile->cur_run);
	  pfile->cur_token = pfile->cur_run->base;
	}
      /* We assume that the current token is somewhere in the current
	 run.  */
      if (pfile->cur_token < pfile->cur_run->base
	  || pfile->cur_token >= pfile->cur_run->limit)
	abort ();

      if (pfile->lookaheads)
	{
	  pfile->lookaheads--;
	  result = pfile->cur_token++;
	}
      else
	result = _cpp_lex_direct (pfile);

      if (result->flags & BOL)
	{
	  /* Is this a directive.  If _cpp_handle_directive returns
	     false, it is an assembler #.  */
	  if (result->type == CPP_HASH
	      /* 6.10.3 p 11: Directives in a list of macro arguments
		 gives undefined behavior.  This implementation
		 handles the directive as normal.  */
	      && pfile->state.parsing_args != 1)
	    {
	      if (_cpp_handle_directive (pfile, result->flags & PREV_WHITE))
		{
		  if (pfile->directive_result.type == CPP_PADDING)
		    continue;
		  result = &pfile->directive_result;
		}
	    }
	  else if (pfile->state.in_deferred_pragma)
	    result = &pfile->directive_result;

	  if (pfile->cb.line_change && !pfile->state.skipping)
	    pfile->cb.line_change (pfile, result, pfile->state.parsing_args);
	}

      /* We don't skip tokens in directives.  */
      if (pfile->state.in_directive || pfile->state.in_deferred_pragma)
	break;

      /* Outside a directive, invalidate controlling macros.  At file
	 EOF, _cpp_lex_direct takes care of popping the buffer, so we never
	 get here and MI optimization works.  */
      pfile->mi_valid = false;

      if (!pfile->state.skipping || result->type == CPP_EOF)
	break;
    }

  return result;
}

/* Returns true if a fresh line has been loaded.  */
bool
_cpp_get_fresh_line (cpp_reader *pfile)
{
  int return_at_eof;

  /* We can't get a new line until we leave the current directive.  */
  if (pfile->state.in_directive)
    return false;

  for (;;)
    {
      cpp_buffer *buffer = pfile->buffer;

      if (!buffer->need_line)
	return true;

      if (buffer->next_line < buffer->rlimit)
	{
	  _cpp_clean_line (pfile);
	  return true;
	}

      /* First, get out of parsing arguments state.  */
      if (pfile->state.parsing_args)
	return false;

      /* End of buffer.  Non-empty files should end in a newline.  */
      if (buffer->buf != buffer->rlimit
	  && buffer->next_line > buffer->rlimit
	  && !buffer->from_stage3)
	{
	  /* Clip to buffer size.  */
	  buffer->next_line = buffer->rlimit;
	}

      return_at_eof = buffer->return_at_eof;
      _cpp_pop_buffer (pfile);
      if (pfile->buffer == NULL || return_at_eof)
	return false;
    }
}

#define IF_NEXT_IS(CHAR, THEN_TYPE, ELSE_TYPE)		\
  do							\
    {							\
      result->type = ELSE_TYPE;				\
      if (*buffer->cur == CHAR)				\
	buffer->cur++, result->type = THEN_TYPE;	\
    }							\
  while (0)

/* Lex a token into pfile->cur_token, which is also incremented, to
   get diagnostics pointing to the correct location.

   Does not handle issues such as token lookahead, multiple-include
   optimization, directives, skipping etc.  This function is only
   suitable for use by _cpp_lex_token, and in special cases like
   lex_expansion_token which doesn't care for any of these issues.

   When meeting a newline, returns CPP_EOF if parsing a directive,
   otherwise returns to the start of the token buffer if permissible.
   Returns the location of the lexed token.  */
cpp_token *
_cpp_lex_direct (cpp_reader *pfile)
{
  cppchar_t c;
  cpp_buffer *buffer;
  const unsigned char *comment_start;
  bool fallthrough_comment = false;
  cpp_token *result = pfile->cur_token++;

 fresh_line:
  result->flags = 0;
  buffer = pfile->buffer;
  if (buffer->need_line)
    {
      if (pfile->state.in_deferred_pragma)
	{
	  result->type = CPP_PRAGMA_EOL;
	  pfile->state.in_deferred_pragma = false;
	  if (!pfile->state.pragma_allow_expansion)
	    pfile->state.prevent_expansion--;
	  return result;
	}
      if (!_cpp_get_fresh_line (pfile))
	{
	  result->type = CPP_EOF;
	  if (!pfile->state.in_directive)
	    {
	      /* Tell the compiler the line number of the EOF token.  */
	      result->src_loc = pfile->line_table->highest_line;
	      result->flags = BOL;
	    }
	  return result;
	}
      if (buffer != pfile->buffer)
	fallthrough_comment = false;
      if (!pfile->keep_tokens)
	{
	  pfile->cur_run = &pfile->base_run;
	  result = pfile->base_run.base;
	  pfile->cur_token = result + 1;
	}
      result->flags = BOL;
      if (pfile->state.parsing_args == 2)
	result->flags |= PREV_WHITE;
    }
  buffer = pfile->buffer;
 update_tokens_line:
  result->src_loc = pfile->line_table->highest_line;

 skipped_white:
  if (buffer->cur >= buffer->notes[buffer->cur_note].pos
      && !pfile->overlaid_buffer)
    {
      _cpp_process_line_notes (pfile, false);
      result->src_loc = pfile->line_table->highest_line;
    }
  c = *buffer->cur++;

  if (pfile->forced_token_location)
    result->src_loc = pfile->forced_token_location;
  else
    result->src_loc = linemap_position_for_column (pfile->line_table,
					  CPP_BUF_COLUMN (buffer, buffer->cur));

  switch (c)
    {
    case ' ': case '\t': case '\f': case '\v': case '\0':
      result->flags |= PREV_WHITE;
      skip_whitespace (pfile, c);
      goto skipped_white;

    case '\n':
      /* Increment the line, unless this is the last line ...  */
      if (buffer->cur < buffer->rlimit
	  /* ... or this is a #include, (where _cpp_stack_file needs to
	     unwind by one line) ...  */
	  || (pfile->state.in_directive > 1
	      /* ... except traditional-cpp increments this elsewhere.  */
	      && !CPP_OPTION (pfile, traditional)))
	CPP_INCREMENT_LINE (pfile, 0);
      buffer->need_line = true;
      goto fresh_line;

    case '0': case '1': case '2': case '3': case '4':
    case '5': case '6': case '7': case '8': case '9':
      {
	struct normalize_state nst = INITIAL_NORMALIZE_STATE;
	result->type = CPP_NUMBER;
	lex_number (pfile, &result->val.str, &nst);
	warn_about_normalization (pfile, result, &nst);
	break;
      }

    case 'L':
    case 'u':
    case 'U':
    case 'R':
      /* 'L', 'u', 'U', 'u8' or 'R' may introduce wide characters,
	 wide strings or raw strings.  */
      if (c == 'L' || CPP_OPTION (pfile, rliterals)
	  || (c != 'R' && CPP_OPTION (pfile, uliterals)))
	{
	  if ((*buffer->cur == '\'' && c != 'R')
	      || *buffer->cur == '"'
	      || (*buffer->cur == 'R'
		  && c != 'R'
		  && buffer->cur[1] == '"'
		  && CPP_OPTION (pfile, rliterals))
	      || (*buffer->cur == '8'
		  && c == 'u'
		  && ((buffer->cur[1] == '"' || (buffer->cur[1] == '\''
				&& CPP_OPTION (pfile, utf8_char_literals)))
		      || (buffer->cur[1] == 'R' && buffer->cur[2] == '"'
			  && CPP_OPTION (pfile, rliterals)))))
	    {
	      lex_string (pfile, result, buffer->cur - 1);
	      break;
	    }
	}
      /* Fall through.  */

    case '_':
    case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
    case 'g': case 'h': case 'i': case 'j': case 'k': case 'l':
    case 'm': case 'n': case 'o': case 'p': case 'q': case 'r':
    case 's': case 't':           case 'v': case 'w': case 'x':
    case 'y': case 'z':
    case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
    case 'G': case 'H': case 'I': case 'J': case 'K':
    case 'M': case 'N': case 'O': case 'P': case 'Q':
    case 'S': case 'T':           case 'V': case 'W': case 'X':
    case 'Y': case 'Z':
      result->type = CPP_NAME;
      {
	struct normalize_state nst = INITIAL_NORMALIZE_STATE;
	result->val.node.node = lex_identifier (pfile, buffer->cur - 1, false,
						&nst,
						&result->val.node.spelling);
	warn_about_normalization (pfile, result, &nst);
      }

      /* Convert named operators to their proper types.  */
      if (result->val.node.node->flags & NODE_OPERATOR)
	{
	  result->flags |= NAMED_OP;
	  result->type = (enum cpp_ttype) result->val.node.node->directive_index;
	}

      /* Signal FALLTHROUGH comment followed by another token.  */
      if (fallthrough_comment)
	result->flags |= PREV_FALLTHROUGH;
      break;

    case '\'':
    case '"':
      lex_string (pfile, result, buffer->cur - 1);
      break;

    case '/':
      /* A potential block or line comment.  */
      comment_start = buffer->cur;
      c = *buffer->cur;
      
      if (c == '*')
	{
	  if (_cpp_skip_block_comment (pfile))
	    cpp_error (pfile, CPP_DL_ERROR, "unterminated comment");
	}
      else if (c == '/' && ! CPP_OPTION (pfile, traditional))
	{
	  /* Don't warn for system headers.  */
	  if (cpp_in_system_header (pfile))
	    ;
	  /* Warn about comments if pedantically GNUC89, and not
	     in system headers.  */
	  else if (CPP_OPTION (pfile, lang) == CLK_GNUC89
		   && CPP_PEDANTIC (pfile)
		   && ! buffer->warned_cplusplus_comments)
	    {
	      if (cpp_error (pfile, CPP_DL_PEDWARN,
			     "C++ style comments are not allowed in ISO C90"))
		cpp_error (pfile, CPP_DL_NOTE,
			   "(this will be reported only once per input file)");
	      buffer->warned_cplusplus_comments = 1;
	    }
	  /* Or if specifically desired via -Wc90-c99-compat.  */
	  else if (CPP_OPTION (pfile, cpp_warn_c90_c99_compat) > 0
		   && ! CPP_OPTION (pfile, cplusplus)
		   && ! buffer->warned_cplusplus_comments)
	    {
	      if (cpp_error (pfile, CPP_DL_WARNING,
			     "C++ style comments are incompatible with C90"))
		cpp_error (pfile, CPP_DL_NOTE,
			   "(this will be reported only once per input file)");
	      buffer->warned_cplusplus_comments = 1;
	    }
	  /* In C89/C94, C++ style comments are forbidden.  */
	  else if ((CPP_OPTION (pfile, lang) == CLK_STDC89
		    || CPP_OPTION (pfile, lang) == CLK_STDC94))
	    {
	      /* But don't be confused about valid code such as
	         - // immediately followed by *,
		 - // in a preprocessing directive,
		 - // in an #if 0 block.  */
	      if (buffer->cur[1] == '*'
		  || pfile->state.in_directive
		  || pfile->state.skipping)
		{
		  result->type = CPP_DIV;
		  break;
		}
	      else if (! buffer->warned_cplusplus_comments)
		{
		  if (cpp_error (pfile, CPP_DL_ERROR,
				 "C++ style comments are not allowed in "
				 "ISO C90"))
		    cpp_error (pfile, CPP_DL_NOTE,
			       "(this will be reported only once per input "
			       "file)");
		  buffer->warned_cplusplus_comments = 1;
		}
	    }
	  if (skip_line_comment (pfile) && CPP_OPTION (pfile, warn_comments))
	    cpp_warning (pfile, CPP_W_COMMENTS, "multi-line comment");
	}
      else if (c == '=')
	{
	  buffer->cur++;
	  result->type = CPP_DIV_EQ;
	  break;
	}
      else
	{
	  result->type = CPP_DIV;
	  break;
	}

      if (fallthrough_comment_p (pfile, comment_start))
	fallthrough_comment = true;

      if (pfile->cb.comment)
	{
	  size_t len = pfile->buffer->cur - comment_start;
	  pfile->cb.comment (pfile, result->src_loc, comment_start - 1,
			     len + 1);
	}

      if (!pfile->state.save_comments)
	{
	  result->flags |= PREV_WHITE;
	  goto update_tokens_line;
	}

      if (fallthrough_comment)
	result->flags |= PREV_FALLTHROUGH;

      /* Save the comment as a token in its own right.  */
      save_comment (pfile, result, comment_start, c);
      break;

    case '<':
      if (pfile->state.angled_headers)
	{
	  lex_string (pfile, result, buffer->cur - 1);
	  if (result->type != CPP_LESS)
	    break;
	}

      result->type = CPP_LESS;
      if (*buffer->cur == '=')
	{
	  buffer->cur++, result->type = CPP_LESS_EQ;
	  if (*buffer->cur == '>'
	      && CPP_OPTION (pfile, cplusplus)
	      && CPP_OPTION (pfile, lang) >= CLK_GNUCXX2A)
	    buffer->cur++, result->type = CPP_SPACESHIP;
	}
      else if (*buffer->cur == '<')
	{
	  buffer->cur++;
	  IF_NEXT_IS ('=', CPP_LSHIFT_EQ, CPP_LSHIFT);
	}
      else if (CPP_OPTION (pfile, digraphs))
	{
	  if (*buffer->cur == ':')
	    {
	      /* C++11 [2.5/3 lex.pptoken], "Otherwise, if the next
		 three characters are <:: and the subsequent character
		 is neither : nor >, the < is treated as a preprocessor
		 token by itself".  */
	      if (CPP_OPTION (pfile, cplusplus)
		  && CPP_OPTION (pfile, lang) != CLK_CXX98
		  && CPP_OPTION (pfile, lang) != CLK_GNUCXX
		  && buffer->cur[1] == ':'
		  && buffer->cur[2] != ':' && buffer->cur[2] != '>')
		break;

	      buffer->cur++;
	      result->flags |= DIGRAPH;
	      result->type = CPP_OPEN_SQUARE;
	    }
	  else if (*buffer->cur == '%')
	    {
	      buffer->cur++;
	      result->flags |= DIGRAPH;
	      result->type = CPP_OPEN_BRACE;
	    }
	}
      break;

    case '>':
      result->type = CPP_GREATER;
      if (*buffer->cur == '=')
	buffer->cur++, result->type = CPP_GREATER_EQ;
      else if (*buffer->cur == '>')
	{
	  buffer->cur++;
	  IF_NEXT_IS ('=', CPP_RSHIFT_EQ, CPP_RSHIFT);
	}
      break;

    case '%':
      result->type = CPP_MOD;
      if (*buffer->cur == '=')
	buffer->cur++, result->type = CPP_MOD_EQ;
      else if (CPP_OPTION (pfile, digraphs))
	{
	  if (*buffer->cur == ':')
	    {
	      buffer->cur++;
	      result->flags |= DIGRAPH;
	      result->type = CPP_HASH;
	      if (*buffer->cur == '%' && buffer->cur[1] == ':')
		buffer->cur += 2, result->type = CPP_PASTE, result->val.token_no = 0;
	    }
	  else if (*buffer->cur == '>')
	    {
	      buffer->cur++;
	      result->flags |= DIGRAPH;
	      result->type = CPP_CLOSE_BRACE;
	    }
	}
      break;

    case '.':
      result->type = CPP_DOT;
      if (ISDIGIT (*buffer->cur))
	{
	  struct normalize_state nst = INITIAL_NORMALIZE_STATE;
	  result->type = CPP_NUMBER;
	  lex_number (pfile, &result->val.str, &nst);
	  warn_about_normalization (pfile, result, &nst);
	}
      else if (*buffer->cur == '.' && buffer->cur[1] == '.')
	buffer->cur += 2, result->type = CPP_ELLIPSIS;
      else if (*buffer->cur == '*' && CPP_OPTION (pfile, cplusplus))
	buffer->cur++, result->type = CPP_DOT_STAR;
      break;

    case '+':
      result->type = CPP_PLUS;
      if (*buffer->cur == '+')
	buffer->cur++, result->type = CPP_PLUS_PLUS;
      else if (*buffer->cur == '=')
	buffer->cur++, result->type = CPP_PLUS_EQ;
      break;

    case '-':
      result->type = CPP_MINUS;
      if (*buffer->cur == '>')
	{
	  buffer->cur++;
	  result->type = CPP_DEREF;
	  if (*buffer->cur == '*' && CPP_OPTION (pfile, cplusplus))
	    buffer->cur++, result->type = CPP_DEREF_STAR;
	}
      else if (*buffer->cur == '-')
	buffer->cur++, result->type = CPP_MINUS_MINUS;
      else if (*buffer->cur == '=')
	buffer->cur++, result->type = CPP_MINUS_EQ;
      break;

    case '&':
      result->type = CPP_AND;
      if (*buffer->cur == '&')
	buffer->cur++, result->type = CPP_AND_AND;
      else if (*buffer->cur == '=')
	buffer->cur++, result->type = CPP_AND_EQ;
      break;

    case '|':
      result->type = CPP_OR;
      if (*buffer->cur == '|')
	buffer->cur++, result->type = CPP_OR_OR;
      else if (*buffer->cur == '=')
	buffer->cur++, result->type = CPP_OR_EQ;
      break;

    case ':':
      result->type = CPP_COLON;
      if (*buffer->cur == ':' && CPP_OPTION (pfile, scope))
	buffer->cur++, result->type = CPP_SCOPE;
      else if (*buffer->cur == '>' && CPP_OPTION (pfile, digraphs))
	{
	  buffer->cur++;
	  result->flags |= DIGRAPH;
	  result->type = CPP_CLOSE_SQUARE;
	}
      break;

    case '*': IF_NEXT_IS ('=', CPP_MULT_EQ, CPP_MULT); break;
    case '=': IF_NEXT_IS ('=', CPP_EQ_EQ, CPP_EQ); break;
    case '!': IF_NEXT_IS ('=', CPP_NOT_EQ, CPP_NOT); break;
    case '^': IF_NEXT_IS ('=', CPP_XOR_EQ, CPP_XOR); break;
    case '#': IF_NEXT_IS ('#', CPP_PASTE, CPP_HASH); result->val.token_no = 0; break;

    case '?': result->type = CPP_QUERY; break;
    case '~': result->type = CPP_COMPL; break;
    case ',': result->type = CPP_COMMA; break;
    case '(': result->type = CPP_OPEN_PAREN; break;
    case ')': result->type = CPP_CLOSE_PAREN; break;
    case '[': result->type = CPP_OPEN_SQUARE; break;
    case ']': result->type = CPP_CLOSE_SQUARE; break;
    case '{': result->type = CPP_OPEN_BRACE; break;
    case '}': result->type = CPP_CLOSE_BRACE; break;
    case ';': result->type = CPP_SEMICOLON; break;

      /* @ is a punctuator in Objective-C.  */
    case '@': result->type = CPP_ATSIGN; break;

    default:
      {
	const uchar *base = --buffer->cur;

	/* Check for an extended identifier ($ or UCN or UTF-8).  */
	struct normalize_state nst = INITIAL_NORMALIZE_STATE;
	if (forms_identifier_p (pfile, true, &nst))
	  {
	    result->type = CPP_NAME;
	    result->val.node.node = lex_identifier (pfile, base, true, &nst,
						    &result->val.node.spelling);
	    warn_about_normalization (pfile, result, &nst);
	    break;
	  }

	/* Otherwise this will form a CPP_OTHER token.  Parse valid UTF-8 as a
	   single token.  */
	buffer->cur++;
	if (c >= utf8_signifier)
	  {
	    const uchar *pstr = base;
	    cppchar_t s;
	    if (_cpp_valid_utf8 (pfile, &pstr, buffer->rlimit, 0, NULL, &s))
	      buffer->cur = pstr;
	  }
	create_literal (pfile, result, base, buffer->cur - base, CPP_OTHER);
	break;
      }

    }

  /* Potentially convert the location of the token to a range.  */
  if (result->src_loc >= RESERVED_LOCATION_COUNT
      && result->type != CPP_EOF)
    {
      /* Ensure that any line notes are processed, so that we have the
	 correct physical line/column for the end-point of the token even
	 when a logical line is split via one or more backslashes.  */
      if (buffer->cur >= buffer->notes[buffer->cur_note].pos
	  && !pfile->overlaid_buffer)
	_cpp_process_line_notes (pfile, false);

      source_range tok_range;
      tok_range.m_start = result->src_loc;
      tok_range.m_finish
	= linemap_position_for_column (pfile->line_table,
				       CPP_BUF_COLUMN (buffer, buffer->cur));

      result->src_loc = COMBINE_LOCATION_DATA (pfile->line_table,
					       result->src_loc,
					       tok_range, NULL);
    }

  return result;
}

/* An upper bound on the number of bytes needed to spell TOKEN.
   Does not include preceding whitespace.  */
unsigned int
cpp_token_len (const cpp_token *token)
{
  unsigned int len;

  switch (TOKEN_SPELL (token))
    {
    default:		len = 6;				break;
    case SPELL_LITERAL:	len = token->val.str.len;		break;
    case SPELL_IDENT:	len = NODE_LEN (token->val.node.node) * 10;	break;
    }

  return len;
}

/* Parse UTF-8 out of NAMEP and place a \U escape in BUFFER.
   Return the number of bytes read out of NAME.  (There are always
   10 bytes written to BUFFER.)  */

static size_t
utf8_to_ucn (unsigned char *buffer, const unsigned char *name)
{
  int j;
  int ucn_len = 0;
  int ucn_len_c;
  unsigned t;
  unsigned long utf32;
  
  /* Compute the length of the UTF-8 sequence.  */
  for (t = *name; t & 0x80; t <<= 1)
    ucn_len++;
  
  utf32 = *name & (0x7F >> ucn_len);
  for (ucn_len_c = 1; ucn_len_c < ucn_len; ucn_len_c++)
    {
      utf32 = (utf32 << 6) | (*++name & 0x3F);
      
      /* Ill-formed UTF-8.  */
      if ((*name & ~0x3F) != 0x80)
	abort ();
    }
  
  *buffer++ = '\\';
  *buffer++ = 'U';
  for (j = 7; j >= 0; j--)
    *buffer++ = "0123456789abcdef"[(utf32 >> (4 * j)) & 0xF];
  return ucn_len;
}

/* Given a token TYPE corresponding to a digraph, return a pointer to
   the spelling of the digraph.  */
static const unsigned char *
cpp_digraph2name (enum cpp_ttype type)
{
  return digraph_spellings[(int) type - (int) CPP_FIRST_DIGRAPH];
}

/* Write the spelling of an identifier IDENT, using UCNs, to BUFFER.
   The buffer must already contain the enough space to hold the
   token's spelling.  Returns a pointer to the character after the
   last character written.  */
unsigned char *
_cpp_spell_ident_ucns (unsigned char *buffer, cpp_hashnode *ident)
{
  size_t i;
  const unsigned char *name = NODE_NAME (ident);
	  
  for (i = 0; i < NODE_LEN (ident); i++)
    if (name[i] & ~0x7F)
      {
	i += utf8_to_ucn (buffer, name + i) - 1;
	buffer += 10;
      }
    else
      *buffer++ = name[i];

  return buffer;
}

/* Write the spelling of a token TOKEN to BUFFER.  The buffer must
   already contain the enough space to hold the token's spelling.
   Returns a pointer to the character after the last character written.
   FORSTRING is true if this is to be the spelling after translation
   phase 1 (with the original spelling of extended identifiers), false
   if extended identifiers should always be written using UCNs (there is
   no option for always writing them in the internal UTF-8 form).
   FIXME: Would be nice if we didn't need the PFILE argument.  */
unsigned char *
cpp_spell_token (cpp_reader *pfile, const cpp_token *token,
		 unsigned char *buffer, bool forstring)
{
  switch (TOKEN_SPELL (token))
    {
    case SPELL_OPERATOR:
      {
	const unsigned char *spelling;
	unsigned char c;

	if (token->flags & DIGRAPH)
	  spelling = cpp_digraph2name (token->type);
	else if (token->flags & NAMED_OP)
	  goto spell_ident;
	else
	  spelling = TOKEN_NAME (token);

	while ((c = *spelling++) != '\0')
	  *buffer++ = c;
      }
      break;

    spell_ident:
    case SPELL_IDENT:
      if (forstring)
	{
	  memcpy (buffer, NODE_NAME (token->val.node.spelling),
		  NODE_LEN (token->val.node.spelling));
	  buffer += NODE_LEN (token->val.node.spelling);
	}
      else
	buffer = _cpp_spell_ident_ucns (buffer, token->val.node.node);
      break;

    case SPELL_LITERAL:
      memcpy (buffer, token->val.str.text, token->val.str.len);
      buffer += token->val.str.len;
      break;

    case SPELL_NONE:
      cpp_error (pfile, CPP_DL_ICE,
		 "unspellable token %s", TOKEN_NAME (token));
      break;
    }

  return buffer;
}

/* Returns TOKEN spelt as a null-terminated string.  The string is
   freed when the reader is destroyed.  Useful for diagnostics.  */
unsigned char *
cpp_token_as_text (cpp_reader *pfile, const cpp_token *token)
{ 
  unsigned int len = cpp_token_len (token) + 1;
  unsigned char *start = _cpp_unaligned_alloc (pfile, len), *end;

  end = cpp_spell_token (pfile, token, start, false);
  end[0] = '\0';

  return start;
}

/* Returns a pointer to a string which spells the token defined by
   TYPE and FLAGS.  Used by C front ends, which really should move to
   using cpp_token_as_text.  */
const char *
cpp_type2name (enum cpp_ttype type, unsigned char flags)
{
  if (flags & DIGRAPH)
    return (const char *) cpp_digraph2name (type);
  else if (flags & NAMED_OP)
    return cpp_named_operator2name (type);

  return (const char *) token_spellings[type].name;
}

/* Writes the spelling of token to FP, without any preceding space.
   Separated from cpp_spell_token for efficiency - to avoid stdio
   double-buffering.  */
void
cpp_output_token (const cpp_token *token, FILE *fp)
{
  switch (TOKEN_SPELL (token))
    {
    case SPELL_OPERATOR:
      {
	const unsigned char *spelling;
	int c;

	if (token->flags & DIGRAPH)
	  spelling = cpp_digraph2name (token->type);
	else if (token->flags & NAMED_OP)
	  goto spell_ident;
	else
	  spelling = TOKEN_NAME (token);

	c = *spelling;
	do
	  putc (c, fp);
	while ((c = *++spelling) != '\0');
      }
      break;

    spell_ident:
    case SPELL_IDENT:
      {
	size_t i;
	const unsigned char * name = NODE_NAME (token->val.node.node);
	
	for (i = 0; i < NODE_LEN (token->val.node.node); i++)
	  if (name[i] & ~0x7F)
	    {
	      unsigned char buffer[10];
	      i += utf8_to_ucn (buffer, name + i) - 1;
	      fwrite (buffer, 1, 10, fp);
	    }
	  else
	    fputc (NODE_NAME (token->val.node.node)[i], fp);
      }
      break;

    case SPELL_LITERAL:
      fwrite (token->val.str.text, 1, token->val.str.len, fp);
      break;

    case SPELL_NONE:
      /* An error, most probably.  */
      break;
    }
}

/* Compare two tokens.  */
int
_cpp_equiv_tokens (const cpp_token *a, const cpp_token *b)
{
  if (a->type == b->type && a->flags == b->flags)
    switch (TOKEN_SPELL (a))
      {
      default:			/* Keep compiler happy.  */
      case SPELL_OPERATOR:
	/* token_no is used to track where multiple consecutive ##
	   tokens were originally located.  */
	return (a->type != CPP_PASTE || a->val.token_no == b->val.token_no);
      case SPELL_NONE:
	return (a->type != CPP_MACRO_ARG
		|| (a->val.macro_arg.arg_no == b->val.macro_arg.arg_no
		    && a->val.macro_arg.spelling == b->val.macro_arg.spelling));
      case SPELL_IDENT:
	return (a->val.node.node == b->val.node.node
		&& a->val.node.spelling == b->val.node.spelling);
      case SPELL_LITERAL:
	return (a->val.str.len == b->val.str.len
		&& !memcmp (a->val.str.text, b->val.str.text,
			    a->val.str.len));
      }

  return 0;
}

/* Returns nonzero if a space should be inserted to avoid an
   accidental token paste for output.  For simplicity, it is
   conservative, and occasionally advises a space where one is not
   needed, e.g. "." and ".2".  */
int
cpp_avoid_paste (cpp_reader *pfile, const cpp_token *token1,
		 const cpp_token *token2)
{
  enum cpp_ttype a = token1->type, b = token2->type;
  cppchar_t c;

  if (token1->flags & NAMED_OP)
    a = CPP_NAME;
  if (token2->flags & NAMED_OP)
    b = CPP_NAME;

  c = EOF;
  if (token2->flags & DIGRAPH)
    c = digraph_spellings[(int) b - (int) CPP_FIRST_DIGRAPH][0];
  else if (token_spellings[b].category == SPELL_OPERATOR)
    c = token_spellings[b].name[0];

  /* Quickly get everything that can paste with an '='.  */
  if ((int) a <= (int) CPP_LAST_EQ && c == '=')
    return 1;

  switch (a)
    {
    case CPP_GREATER:	return c == '>';
    case CPP_LESS:	return c == '<' || c == '%' || c == ':';
    case CPP_PLUS:	return c == '+';
    case CPP_MINUS:	return c == '-' || c == '>';
    case CPP_DIV:	return c == '/' || c == '*'; /* Comments.  */
    case CPP_MOD:	return c == ':' || c == '>';
    case CPP_AND:	return c == '&';
    case CPP_OR:	return c == '|';
    case CPP_COLON:	return c == ':' || c == '>';
    case CPP_DEREF:	return c == '*';
    case CPP_DOT:	return c == '.' || c == '%' || b == CPP_NUMBER;
    case CPP_HASH:	return c == '#' || c == '%'; /* Digraph form.  */
    case CPP_NAME:	return ((b == CPP_NUMBER
				 && name_p (pfile, &token2->val.str))
				|| b == CPP_NAME
				|| b == CPP_CHAR || b == CPP_STRING); /* L */
    case CPP_NUMBER:	return (b == CPP_NUMBER || b == CPP_NAME
				|| c == '.' || c == '+' || c == '-');
				      /* UCNs */
    case CPP_OTHER:	return ((token1->val.str.text[0] == '\\'
				 && b == CPP_NAME)
				|| (CPP_OPTION (pfile, objc)
				    && token1->val.str.text[0] == '@'
				    && (b == CPP_NAME || b == CPP_STRING)));
    case CPP_LESS_EQ:	return c == '>';
    case CPP_STRING:
    case CPP_WSTRING:
    case CPP_UTF8STRING:
    case CPP_STRING16:
    case CPP_STRING32:	return (CPP_OPTION (pfile, user_literals)
				&& (b == CPP_NAME
				    || (TOKEN_SPELL (token2) == SPELL_LITERAL
					&& ISIDST (token2->val.str.text[0]))));

    default:		break;
    }

  return 0;
}

/* Output all the remaining tokens on the current line, and a newline
   character, to FP.  Leading whitespace is removed.  If there are
   macros, special token padding is not performed.  */
void
cpp_output_line (cpp_reader *pfile, FILE *fp)
{
  const cpp_token *token;

  token = cpp_get_token (pfile);
  while (token->type != CPP_EOF)
    {
      cpp_output_token (token, fp);
      token = cpp_get_token (pfile);
      if (token->flags & PREV_WHITE)
	putc (' ', fp);
    }

  putc ('\n', fp);
}

/* Return a string representation of all the remaining tokens on the
   current line.  The result is allocated using xmalloc and must be
   freed by the caller.  */
unsigned char *
cpp_output_line_to_string (cpp_reader *pfile, const unsigned char *dir_name)
{
  const cpp_token *token;
  unsigned int out = dir_name ? ustrlen (dir_name) : 0;
  unsigned int alloced = 120 + out;
  unsigned char *result = (unsigned char *) xmalloc (alloced);

  /* If DIR_NAME is empty, there are no initial contents.  */
  if (dir_name)
    {
      sprintf ((char *) result, "#%s ", dir_name);
      out += 2;
    }

  token = cpp_get_token (pfile);
  while (token->type != CPP_EOF)
    {
      unsigned char *last;
      /* Include room for a possible space and the terminating nul.  */
      unsigned int len = cpp_token_len (token) + 2;

      if (out + len > alloced)
	{
	  alloced *= 2;
	  if (out + len > alloced)
	    alloced = out + len;
	  result = (unsigned char *) xrealloc (result, alloced);
	}

      last = cpp_spell_token (pfile, token, &result[out], 0);
      out = last - result;

      token = cpp_get_token (pfile);
      if (token->flags & PREV_WHITE)
	result[out++] = ' ';
    }

  result[out] = '\0';
  return result;
}

/* Memory buffers.  Changing these three constants can have a dramatic
   effect on performance.  The values here are reasonable defaults,
   but might be tuned.  If you adjust them, be sure to test across a
   range of uses of cpplib, including heavy nested function-like macro
   expansion.  Also check the change in peak memory usage (NJAMD is a
   good tool for this).  */
#define MIN_BUFF_SIZE 8000
#define BUFF_SIZE_UPPER_BOUND(MIN_SIZE) (MIN_BUFF_SIZE + (MIN_SIZE) * 3 / 2)
#define EXTENDED_BUFF_SIZE(BUFF, MIN_EXTRA) \
	(MIN_EXTRA + ((BUFF)->limit - (BUFF)->cur) * 2)

#if MIN_BUFF_SIZE > BUFF_SIZE_UPPER_BOUND (0)
  #error BUFF_SIZE_UPPER_BOUND must be at least as large as MIN_BUFF_SIZE!
#endif

/* Create a new allocation buffer.  Place the control block at the end
   of the buffer, so that buffer overflows will cause immediate chaos.  */
static _cpp_buff *
new_buff (size_t len)
{
  _cpp_buff *result;
  unsigned char *base;

  if (len < MIN_BUFF_SIZE)
    len = MIN_BUFF_SIZE;
  len = CPP_ALIGN (len);

#ifdef ENABLE_VALGRIND_ANNOTATIONS
  /* Valgrind warns about uses of interior pointers, so put _cpp_buff
     struct first.  */
  size_t slen = CPP_ALIGN2 (sizeof (_cpp_buff), 2 * DEFAULT_ALIGNMENT);
  base = XNEWVEC (unsigned char, len + slen);
  result = (_cpp_buff *) base;
  base += slen;
#else
  base = XNEWVEC (unsigned char, len + sizeof (_cpp_buff));
  result = (_cpp_buff *) (base + len);
#endif
  result->base = base;
  result->cur = base;
  result->limit = base + len;
  result->next = NULL;
  return result;
}

/* Place a chain of unwanted allocation buffers on the free list.  */
void
_cpp_release_buff (cpp_reader *pfile, _cpp_buff *buff)
{
  _cpp_buff *end = buff;

  while (end->next)
    end = end->next;
  end->next = pfile->free_buffs;
  pfile->free_buffs = buff;
}

/* Return a free buffer of size at least MIN_SIZE.  */
_cpp_buff *
_cpp_get_buff (cpp_reader *pfile, size_t min_size)
{
  _cpp_buff *result, **p;

  for (p = &pfile->free_buffs;; p = &(*p)->next)
    {
      size_t size;

      if (*p == NULL)
	return new_buff (min_size);
      result = *p;
      size = result->limit - result->base;
      /* Return a buffer that's big enough, but don't waste one that's
         way too big.  */
      if (size >= min_size && size <= BUFF_SIZE_UPPER_BOUND (min_size))
	break;
    }

  *p = result->next;
  result->next = NULL;
  result->cur = result->base;
  return result;
}

/* Creates a new buffer with enough space to hold the uncommitted
   remaining bytes of BUFF, and at least MIN_EXTRA more bytes.  Copies
   the excess bytes to the new buffer.  Chains the new buffer after
   BUFF, and returns the new buffer.  */
_cpp_buff *
_cpp_append_extend_buff (cpp_reader *pfile, _cpp_buff *buff, size_t min_extra)
{
  size_t size = EXTENDED_BUFF_SIZE (buff, min_extra);
  _cpp_buff *new_buff = _cpp_get_buff (pfile, size);

  buff->next = new_buff;
  memcpy (new_buff->base, buff->cur, BUFF_ROOM (buff));
  return new_buff;
}

/* Creates a new buffer with enough space to hold the uncommitted
   remaining bytes of the buffer pointed to by BUFF, and at least
   MIN_EXTRA more bytes.  Copies the excess bytes to the new buffer.
   Chains the new buffer before the buffer pointed to by BUFF, and
   updates the pointer to point to the new buffer.  */
void
_cpp_extend_buff (cpp_reader *pfile, _cpp_buff **pbuff, size_t min_extra)
{
  _cpp_buff *new_buff, *old_buff = *pbuff;
  size_t size = EXTENDED_BUFF_SIZE (old_buff, min_extra);

  new_buff = _cpp_get_buff (pfile, size);
  memcpy (new_buff->base, old_buff->cur, BUFF_ROOM (old_buff));
  new_buff->next = old_buff;
  *pbuff = new_buff;
}

/* Free a chain of buffers starting at BUFF.  */
void
_cpp_free_buff (_cpp_buff *buff)
{
  _cpp_buff *next;

  for (; buff; buff = next)
    {
      next = buff->next;
#ifdef ENABLE_VALGRIND_ANNOTATIONS
      free (buff);
#else
      free (buff->base);
#endif
    }
}

/* Allocate permanent, unaligned storage of length LEN.  */
unsigned char *
_cpp_unaligned_alloc (cpp_reader *pfile, size_t len)
{
  _cpp_buff *buff = pfile->u_buff;
  unsigned char *result = buff->cur;

  if (len > (size_t) (buff->limit - result))
    {
      buff = _cpp_get_buff (pfile, len);
      buff->next = pfile->u_buff;
      pfile->u_buff = buff;
      result = buff->cur;
    }

  buff->cur = result + len;
  return result;
}

/* Allocate permanent, unaligned storage of length LEN from a_buff.
   That buffer is used for growing allocations when saving macro
   replacement lists in a #define, and when parsing an answer to an
   assertion in #assert, #unassert or #if (and therefore possibly
   whilst expanding macros).  It therefore must not be used by any
   code that they might call: specifically the lexer and the guts of
   the macro expander.

   All existing other uses clearly fit this restriction: storing
   registered pragmas during initialization.  */
unsigned char *
_cpp_aligned_alloc (cpp_reader *pfile, size_t len)
{
  _cpp_buff *buff = pfile->a_buff;
  unsigned char *result = buff->cur;

  if (len > (size_t) (buff->limit - result))
    {
      buff = _cpp_get_buff (pfile, len);
      buff->next = pfile->a_buff;
      pfile->a_buff = buff;
      result = buff->cur;
    }

  buff->cur = result + len;
  return result;
}

/* Commit or allocate storage from a buffer.  */

void *
_cpp_commit_buff (cpp_reader *pfile, size_t size)
{
  void *ptr = BUFF_FRONT (pfile->a_buff);

  if (pfile->hash_table->alloc_subobject)
    {
      void *copy = pfile->hash_table->alloc_subobject (size);
      memcpy (copy, ptr, size);
      ptr = copy;
    }
  else
    BUFF_FRONT (pfile->a_buff) += size;

  return ptr;
}

/* Say which field of TOK is in use.  */

enum cpp_token_fld_kind
cpp_token_val_index (const cpp_token *tok)
{
  switch (TOKEN_SPELL (tok))
    {
    case SPELL_IDENT:
      return CPP_TOKEN_FLD_NODE;
    case SPELL_LITERAL:
      return CPP_TOKEN_FLD_STR;
    case SPELL_OPERATOR:
      /* Operands which were originally spelled as ident keep around
         the node for the exact spelling.  */
      if (tok->flags & NAMED_OP)
	return CPP_TOKEN_FLD_NODE;
      else if (tok->type == CPP_PASTE)
	return CPP_TOKEN_FLD_TOKEN_NO;
      else
	return CPP_TOKEN_FLD_NONE;
    case SPELL_NONE:
      if (tok->type == CPP_MACRO_ARG)
	return CPP_TOKEN_FLD_ARG_NO;
      else if (tok->type == CPP_PADDING)
	return CPP_TOKEN_FLD_SOURCE;
      else if (tok->type == CPP_PRAGMA)
	return CPP_TOKEN_FLD_PRAGMA;
      /* fall through */
    default:
      return CPP_TOKEN_FLD_NONE;
    }
}

/* All tokens lexed in R after calling this function will be forced to
   have their location_t to be P, until
   cpp_stop_forcing_token_locations is called for R.  */

void
cpp_force_token_locations (cpp_reader *r, location_t loc)
{
  r->forced_token_location = loc;
}

/* Go back to assigning locations naturally for lexed tokens.  */

void
cpp_stop_forcing_token_locations (cpp_reader *r)
{
  r->forced_token_location = 0;
}