PR 78534 Change character length from int to size_t

In order to handle large character lengths on (L)LP64 targets, switch
the GFortran character length from an int to a size_t.

This is an ABI change, as procedures with character arguments take
hidden arguments with the character length.

I also changed the _size member in vtables from int to size_t, as
there were some cases where character lengths and sizes were
apparently mixed up and caused regressions otherwise. Although I
haven't tested, this might enable very large derived types as well.

Also, as there are some places in the frontend were negative character
lengths are used as special flag values, in the frontend the character
length is handled as a signed variable of the same size as a size_t,
although in the runtime library it really is size_t.

I haven't changed the character length variables for the co-array
intrinsics, as this is something that may need to be synchronized with
OpenCoarrays.

This is v5 of the patch. v4 was applied but caused breakage on big
endian targets. These have been fixed and tested, thanks to access to
the GCC compile farm.

Overview of v4 of the patch: v3 was applied but had to reverted due to
breaking bootstrap. The fix is in resolve.c:resolve_charlen, where
it's necessary to check that an expression is constant before using
mpz_sgn.

Overview of v3 of the patch: All the issues pointed out by FX's review
of v2 have been fixed. In particular, there are now new functions
gfc_mpz_get_hwi and gfc_mpz_set_hwi, similar to the GMP functions
mpz_get_si and mpz_set_si, except that they get/set a HOST_WIDE_INT
instead of a long value. Similarly, gfc_get_int_expr now takes a
HOST_WIDE_INT instead of a long, gfc_extract_long is replaced by
gfc_extract_hwi. Also, the preliminary work to handle
gfc_charlen_type_node being unsigned has been removed.

Regtested on x86_64-pc-linux-gnu, i686-pc-linux-gnu and
powerpc64-unknown-linux-gnu. Also regtested all three targets by
modifying gfortran-dg.exp to also test with "-g -flto", no new
failures observed.

frontend:

2018-01-05  Janne Blomqvist  <jb@gcc.gnu.org>

	PR fortran/78534
	PR fortran/66310
	* array.c (got_charlen): Use gfc_charlen_int_kind.
	* class.c (gfc_find_derived_vtab): Use gfc_size_kind instead of
	hardcoded kind.
	(find_intrinsic_vtab): Likewise.
	* decl.c (match_char_length): Use gfc_charlen_int_kind.
	(add_init_expr_to_sym): Use gfc_charlen_t and gfc_charlen_int_kind.
	(gfc_match_implicit): Use gfc_charlen_int_kind.
	* dump-parse-tree.c (show_char_const): Use gfc_charlen_t and size_t.
	(show_expr): Use HOST_WIDE_INT_PRINT_DEC.
	* expr.c (gfc_get_character_expr): Length parameter of type
	gfc_charlen_t.
	(gfc_get_int_expr): Value argument of type HOST_WIDE_INT.
	(gfc_extract_hwi): New function.
	(simplify_const_ref): Make string_len of type gfc_charlen_t.
	(gfc_simplify_expr): Use HOST_WIDE_INT for substring refs.
	* frontend-passes.c (optimize_trim): Use gfc_charlen_int_kind.
	* gfortran.h (gfc_mpz_get_hwi): New prototype.
	(gfc_mpz_set_hwi): Likewise.
	(gfc_charlen_t): New typedef.
	(gfc_expr): Use gfc_charlen_t for character lengths.
	(gfc_size_kind): New extern variable.
	(gfc_extract_hwi): New prototype.
	(gfc_get_character_expr): Use gfc_charlen_t for character length.
	(gfc_get_int_expr): Use HOST_WIDE_INT type for value argument.
	* gfortran.texi: Update description of hidden string length argument.
	* iresolve.c (check_charlen_present): Use gfc_charlen_int_kind.
	(gfc_resolve_char_achar): Likewise.
	(gfc_resolve_repeat): Pass string length directly without
	temporary, use gfc_charlen_int_kind.
	(gfc_resolve_transfer): Use gfc_charlen_int_kind.
	* match.c (select_intrinsic_set_tmp): Use HOST_WIDE_INT for charlen.
	* misc.c (gfc_mpz_get_hwi): New function.
	(gfc_mpz_set_hwi): New function.
	* module.c (atom_int): Change type from int to HOST_WIDE_INT.
	(parse_integer): Don't complain about large integers.
	(write_atom): Use HOST_WIDE_INT for integers.
	(mio_integer): Handle integer type mismatch.
	(mio_hwi): New function.
	(mio_intrinsic_op): Use HOST_WIDE_INT.
	(mio_array_ref): Likewise.
	(mio_expr): Likewise.
	* primary.c (match_substring): Use gfc_charlen_int_kind.
	* resolve.c (resolve_substring_charlen): Use gfc_charlen_int_kind.
	(resolve_character_operator): Likewise.
	(resolve_assoc_var): Likewise.
	(resolve_select_type): Use HOST_WIDE_INT for charlen, use snprintf.
	(resolve_charlen): Use mpz_sgn to determine sign.
	* simplify.c (gfc_simplify_repeat): Use HOST_WIDE_INT/gfc_charlen_t
	instead of long.
	* symbol.c (generate_isocbinding_symbol): Use gfc_charlen_int_kind.
	* target-memory.c (size_character): Length argument of type
	gfc_charlen_t.
	(gfc_encode_character): Likewise.
	(gfc_interpret_character): Use gfc_charlen_t.
	* target-memory.h (gfc_encode_character): Modify prototype.
	* trans-array.c (gfc_trans_array_ctor_element): Use existing type.
	(get_array_ctor_var_strlen): Use gfc_conv_mpz_to_tree_type.
	(trans_array_constructor): Use existing type.
	(get_array_charlen): Likewise.
	* trans-const.c (gfc_conv_mpz_to_tree_type): New function.
	* trans-const.h (gfc_conv_mpz_to_tree_type): New prototype.
	* trans-decl.c (gfc_trans_deferred_vars): Use existing type.
	(add_argument_checking): Likewise.
	* trans-expr.c (gfc_class_len_or_zero_get): Build const of type
	gfc_charlen_type_node.
	(gfc_conv_intrinsic_to_class): Use gfc_charlen_int_kind instead of
	4, fold_convert to correct type.
	(gfc_conv_class_to_class): Build const of type size_type_node for
	size.
	(gfc_copy_class_to_class): Likewise.
	(gfc_conv_string_length): Use same type in expression.
	(gfc_conv_substring): Likewise, use HOST_WIDE_INT for charlen.
	(gfc_conv_string_tmp): Make sure len is of the right type.
	(gfc_conv_concat_op): Use same type in expression.
	(gfc_conv_procedure_call): Likewise.
	(fill_with_spaces): Comment out memset() block due to spurious
	-Wstringop-overflow warnings.
	(gfc_trans_string_copy): Use gfc_charlen_type_node.
	(alloc_scalar_allocatable_for_subcomponent_assignment):
	fold_convert to right type.
	(gfc_trans_subcomponent_assign): Likewise.
	(trans_class_vptr_len_assignment): Build const of correct type.
	(gfc_trans_pointer_assignment): Likewise.
	(alloc_scalar_allocatable_for_assignment): fold_convert to right
	type in expr.
	(trans_class_assignment): Build const of correct type.
	* trans-intrinsic.c (gfc_conv_associated): Likewise.
	(gfc_conv_intrinsic_repeat): Do calculation in sizetype.
	* trans-io.c (gfc_build_io_library_fndecls): Use
	gfc_charlen_type_node for character lengths.
	(set_string): Convert to right type in assignment.
	* trans-stmt.c (gfc_trans_label_assign): Build const of
	gfc_charlen_type_node.
	(trans_associate_var): Likewise.
	(gfc_trans_character_select): Likewise.
	(gfc_trans_allocate): Likewise, don't typecast strlen result.
	(gfc_trans_deallocate): Don't typecast strlen result.
	* trans-types.c (gfc_size_kind): New variable.
	(gfc_init_types): Determine gfc_charlen_int_kind and gfc_size_kind
	from size_type_node.
	* trans-types.h: Fix comment.

testsuite:

2018-01-05  Janne Blomqvist  <jb@gcc.gnu.org>

	PR fortran/78534
	PR fortran/66310
	* gfortran.dg/char_cast_1.f90: Update scan pattern.
	* gfortran.dg/dependency_49.f90: Likewise.
	* gfortran.dg/repeat_4.f90: Use integers of kind C_SIZE_T.
	* gfortran.dg/repeat_7.f90: New test for PR 66310.
	* gfortran.dg/scan_2.f90: Handle potential cast in assignment.
	* gfortran.dg/string_1.f90: Limit to ilp32 targets.
	* gfortran.dg/string_1_lp64.f90: New test.
	* gfortran.dg/string_3.f90: Limit to ilp32 targets.
	* gfortran.dg/string_3_lp64.f90: New test.

libgfortran:

2019-01-05  Janne Blomqvist  <jb@gcc.gnu.org>

	PR fortran/78534
	* intrinsics/args.c (getarg_i4): Use gfc_charlen_type.
	(get_command_argument_i4): Likewise.
	(get_command_i4): Likewise.
	* intrinsics/chmod.c (chmod_internal): Likewise.
	* intrinsics/env.c (get_environment_variable_i4): Likewise.
	* intrinsics/extends_type_of.c (struct vtype): Use size_t for size
	member.
	* intrinsics/gerror.c (gerror): Use gfc_charlen_type.
	* intrinsics/getlog.c (getlog): Likewise.
	* intrinsics/hostnm.c (hostnm_0): Likewise.
	* intrinsics/string_intrinsics_inc.c (string_len_trim): Rework to
	work if gfc_charlen_type is unsigned.
	(string_scan): Likewise.
	* io/transfer.c (transfer_character): Modify prototype.
	(transfer_character_write): Likewise.
	(transfer_character_wide): Likewise.
	(transfer_character_wide_write): Likewise.
	(transfer_array): Typecast to avoid signed-unsigned comparison.
	* io/unit.c (is_trim_ok): Use gfc_charlen_type.
	* io/write.c (namelist_write): Likewise.
	* libgfortran.h (gfc_charlen_type): Change typedef to size_t.

From-SVN: r256284

12 files changed, 41 insertions, 41 deletions

diff --git a/libgfortran/intrinsics/args.c b/libgfortran/intrinsics/args.c
index b01b0e8f01c..4c0e5df6341 100644
--- a/libgfortran/intrinsics/args.c
+++ b/libgfortran/intrinsics/args.c
@@ -37,7 +37,6 @@ void
 getarg_i4 (GFC_INTEGER_4 *pos, char  *val, gfc_charlen_type val_len)
 {
   int argc;
-  int arglen;
   char **argv;
 
   get_args (&argc, &argv);
@@ -49,7 +48,7 @@ getarg_i4 (GFC_INTEGER_4 *pos, char  *val, gfc_charlen_type val_len)
 
   if ((*pos) + 1 <= argc  && *pos >=0 )
     {
-      arglen = strlen (argv[*pos]);
+      gfc_charlen_type arglen = strlen (argv[*pos]);
       if (arglen > val_len)
 	arglen = val_len;
       memcpy (val, argv[*pos], arglen);
@@ -119,7 +118,8 @@ get_command_argument_i4 (GFC_INTEGER_4 *number, char *value,
 			 GFC_INTEGER_4 *length, GFC_INTEGER_4 *status, 
 			 gfc_charlen_type value_len)
 {
-  int argc, arglen = 0, stat_flag = GFC_GC_SUCCESS;
+  int argc, stat_flag = GFC_GC_SUCCESS;
+  gfc_charlen_type arglen = 0;
   char **argv;
 
   if (number == NULL )
@@ -195,10 +195,10 @@ void
 get_command_i4 (char *command, GFC_INTEGER_4 *length, GFC_INTEGER_4 *status,
 		gfc_charlen_type command_len)
 {
-  int i, argc, arglen, thisarg;
+  int i, argc, thisarg;
   int stat_flag = GFC_GC_SUCCESS;
-  int tot_len = 0;
   char **argv;
+  gfc_charlen_type arglen, tot_len = 0;
 
   if (command == NULL && length == NULL && status == NULL)
     return; /* No need to do anything.  */
diff --git a/libgfortran/intrinsics/chmod.c b/libgfortran/intrinsics/chmod.c
index d08edc7e146..1299159a7f1 100644
--- a/libgfortran/intrinsics/chmod.c
+++ b/libgfortran/intrinsics/chmod.c
@@ -64,7 +64,6 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 static int
 chmod_internal (char *file, char *mode, gfc_charlen_type mode_len)
 {
-  int i;
   bool ugo[3];
   bool rwxXstugo[9];
   int set_mode, part;
@@ -104,7 +103,7 @@ chmod_internal (char *file, char *mode, gfc_charlen_type mode_len)
   honor_umask = false;
 #endif
 
-  for (i = 0; i < mode_len; i++)
+  for (gfc_charlen_type i = 0; i < mode_len; i++)
     {
       if (!continue_clause)
 	{
diff --git a/libgfortran/intrinsics/env.c b/libgfortran/intrinsics/env.c
index 165f8372935..a2f9498e27f 100644
--- a/libgfortran/intrinsics/env.c
+++ b/libgfortran/intrinsics/env.c
@@ -93,7 +93,8 @@ get_environment_variable_i4 (char *name, char *value, GFC_INTEGER_4 *length,
 			     gfc_charlen_type name_len,
 			     gfc_charlen_type value_len)
 {
-  int stat = GFC_SUCCESS, res_len = 0;
+  int stat = GFC_SUCCESS;
+  gfc_charlen_type res_len = 0;
   char *name_nt;
   char *res;
 
diff --git a/libgfortran/intrinsics/extends_type_of.c b/libgfortran/intrinsics/extends_type_of.c
index b2b8396dbb2..72f40d4f42a 100644
--- a/libgfortran/intrinsics/extends_type_of.c
+++ b/libgfortran/intrinsics/extends_type_of.c
@@ -30,7 +30,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 typedef struct vtype
 {
   GFC_INTEGER_4 hash;
-  GFC_INTEGER_4 size;
+  size_t size;
   struct vtype *extends;
 }
 vtype;
diff --git a/libgfortran/intrinsics/gerror.c b/libgfortran/intrinsics/gerror.c
index c414ab80daf..fc51aad09a7 100644
--- a/libgfortran/intrinsics/gerror.c
+++ b/libgfortran/intrinsics/gerror.c
@@ -39,7 +39,7 @@ export_proto_np(PREFIX(gerror));
 void 
 PREFIX(gerror) (char * msg, gfc_charlen_type msg_len)
 {
-  int p_len;
+  gfc_charlen_type p_len;
   char *p;
 
   p = gf_strerror (errno, msg, msg_len);
diff --git a/libgfortran/intrinsics/getlog.c b/libgfortran/intrinsics/getlog.c
index 7b8f04b7064..518e20faec2 100644
--- a/libgfortran/intrinsics/getlog.c
+++ b/libgfortran/intrinsics/getlog.c
@@ -70,7 +70,6 @@ export_proto_np(PREFIX(getlog));
 void
 PREFIX(getlog) (char * login, gfc_charlen_type login_len)
 {
-  int p_len;
   char *p;
 
   memset (login, ' ', login_len); /* Blank the string.  */
@@ -107,7 +106,7 @@ PREFIX(getlog) (char * login, gfc_charlen_type login_len)
   if (p == NULL)
     goto cleanup;
 
-  p_len = strlen (p);
+  gfc_charlen_type p_len = strlen (p);
   if (login_len < p_len)
     p_len = login_len;
   memcpy (login, p, p_len);
diff --git a/libgfortran/intrinsics/hostnm.c b/libgfortran/intrinsics/hostnm.c
index 62560e92ecd..53d9aec943c 100644
--- a/libgfortran/intrinsics/hostnm.c
+++ b/libgfortran/intrinsics/hostnm.c
@@ -88,8 +88,8 @@ w32_gethostname (char *name, size_t len)
 static int
 hostnm_0 (char *name, gfc_charlen_type name_len)
 {
-  int val, i;
   char p[HOST_NAME_MAX + 1];
+  int val;
 
   memset (name, ' ', name_len);
 
@@ -99,8 +99,7 @@ hostnm_0 (char *name, gfc_charlen_type name_len)
 
   if (val == 0)
   {
-    i = -1;
-    while (i < name_len && p[++i] != '\0')
+    for (gfc_charlen_type i = 0; i < name_len && p[i] != '\0'; i++)
       name[i] = p[i];
   }
 
diff --git a/libgfortran/intrinsics/string_intrinsics_inc.c b/libgfortran/intrinsics/string_intrinsics_inc.c
index 350642d3354..bfec683f528 100644
--- a/libgfortran/intrinsics/string_intrinsics_inc.c
+++ b/libgfortran/intrinsics/string_intrinsics_inc.c
@@ -177,23 +177,25 @@ string_trim (gfc_charlen_type *len, CHARTYPE **dest, gfc_charlen_type slen,
 gfc_charlen_type
 string_len_trim (gfc_charlen_type len, const CHARTYPE *s)
 {
-  const gfc_charlen_type long_len = (gfc_charlen_type) sizeof (unsigned long);
-  gfc_charlen_type i;
+  if (len <= 0)
+    return 0;
 
-  i = len - 1;
+  const size_t long_len = sizeof (unsigned long);
+
+  size_t i = len - 1;
 
   /* If we've got the standard (KIND=1) character type, we scan the string in
      long word chunks to speed it up (until a long word is hit that does not
      consist of ' 's).  */
   if (sizeof (CHARTYPE) == 1 && i >= long_len)
     {
-      int starting;
+      size_t starting;
       unsigned long blank_longword;
 
       /* Handle the first characters until we're aligned on a long word
 	 boundary.  Actually, s + i + 1 must be properly aligned, because
 	 s + i will be the last byte of a long word read.  */
-      starting = ((unsigned long)
+      starting = (
 #ifdef __INTPTR_TYPE__
 		  (__INTPTR_TYPE__)
 #endif
@@ -224,14 +226,15 @@ string_len_trim (gfc_charlen_type len, const CHARTYPE *s)
 	      break;
 	    }
 	}
-
-      /* Now continue for the last characters with naive approach below.  */
-      assert (i >= 0);
     }
 
   /* Simply look for the first non-blank character.  */
-  while (i >= 0 && s[i] == ' ')
-    --i;
+  while (s[i] == ' ')
+    {
+      if (i == 0)
+	return 0;
+      --i;
+    }
   return i + 1;
 }
 
@@ -327,12 +330,12 @@ string_scan (gfc_charlen_type slen, const CHARTYPE *str,
 
   if (back)
     {
-      for (i = slen - 1; i >= 0; i--)
+      for (i = slen; i != 0; i--)
 	{
 	  for (j = 0; j < setlen; j++)
 	    {
-	      if (str[i] == set[j])
-		return (i + 1);
+	      if (str[i - 1] == set[j])
+		return i;
 	    }
 	}
     }
diff --git a/libgfortran/io/transfer.c b/libgfortran/io/transfer.c
index c6431686851..4aafcd0cb57 100644
--- a/libgfortran/io/transfer.c
+++ b/libgfortran/io/transfer.c
@@ -93,17 +93,17 @@ export_proto(transfer_logical);
 extern void transfer_logical_write (st_parameter_dt *, void *, int);
 export_proto(transfer_logical_write);
 
-extern void transfer_character (st_parameter_dt *, void *, int);
+extern void transfer_character (st_parameter_dt *, void *, gfc_charlen_type);
 export_proto(transfer_character);
 
-extern void transfer_character_write (st_parameter_dt *, void *, int);
+extern void transfer_character_write (st_parameter_dt *, void *, gfc_charlen_type);
 export_proto(transfer_character_write);
 
-extern void transfer_character_wide (st_parameter_dt *, void *, int, int);
+extern void transfer_character_wide (st_parameter_dt *, void *, gfc_charlen_type, int);
 export_proto(transfer_character_wide);
 
 extern void transfer_character_wide_write (st_parameter_dt *,
-					   void *, int, int);
+					   void *, gfc_charlen_type, int);
 export_proto(transfer_character_wide_write);
 
 extern void transfer_complex (st_parameter_dt *, void *, int);
@@ -2331,7 +2331,7 @@ transfer_logical_write (st_parameter_dt *dtp, void *p, int kind)
 }
 
 void
-transfer_character (st_parameter_dt *dtp, void *p, int len)
+transfer_character (st_parameter_dt *dtp, void *p, gfc_charlen_type len)
 {
   static char *empty_string[0];
 
@@ -2349,13 +2349,13 @@ transfer_character (st_parameter_dt *dtp, void *p, int len)
 }
 
 void
-transfer_character_write (st_parameter_dt *dtp, void *p, int len)
+transfer_character_write (st_parameter_dt *dtp, void *p, gfc_charlen_type len)
 {
   transfer_character (dtp, p, len);
 }
 
 void
-transfer_character_wide (st_parameter_dt *dtp, void *p, int len, int kind)
+transfer_character_wide (st_parameter_dt *dtp, void *p, gfc_charlen_type len, int kind)
 {
   static char *empty_string[0];
 
@@ -2373,7 +2373,7 @@ transfer_character_wide (st_parameter_dt *dtp, void *p, int len, int kind)
 }
 
 void
-transfer_character_wide_write (st_parameter_dt *dtp, void *p, int len, int kind)
+transfer_character_wide_write (st_parameter_dt *dtp, void *p, gfc_charlen_type len, int kind)
 {
   transfer_character_wide (dtp, p, len, kind);
 }
@@ -2410,7 +2410,7 @@ transfer_array (st_parameter_dt *dtp, gfc_array_char *desc, int kind,
     return;
 
   iotype = (bt) GFC_DESCRIPTOR_TYPE (desc);
-  size = iotype == BT_CHARACTER ? charlen : GFC_DESCRIPTOR_SIZE (desc);
+  size = iotype == BT_CHARACTER ? (index_type) charlen : GFC_DESCRIPTOR_SIZE (desc);
 
   rank = GFC_DESCRIPTOR_RANK (desc);
   for (n = 0; n < rank; n++)
diff --git a/libgfortran/io/unit.c b/libgfortran/io/unit.c
index 0b62ad9cedf..559dba92635 100644
--- a/libgfortran/io/unit.c
+++ b/libgfortran/io/unit.c
@@ -432,10 +432,9 @@ is_trim_ok (st_parameter_dt *dtp)
   if (dtp->common.flags & IOPARM_DT_HAS_FORMAT)
     {
       char *p = dtp->format;
-      off_t i;
       if (dtp->common.flags & IOPARM_DT_HAS_BLANK)
 	return false;
-      for (i = 0; i < dtp->format_len; i++)
+      for (gfc_charlen_type i = 0; i < dtp->format_len; i++)
 	{
 	  if (p[i] == '/') return false;
 	  if (p[i] == 'b' || p[i] == 'B')
diff --git a/libgfortran/io/write.c b/libgfortran/io/write.c
index bd2fb16bf3b..c04d243dc08 100644
--- a/libgfortran/io/write.c
+++ b/libgfortran/io/write.c
@@ -2394,7 +2394,7 @@ namelist_write (st_parameter_dt *dtp)
   write_character (dtp, "&", 1, 1, NODELIM);
 
   /* Write namelist name in upper case - f95 std.  */
-  for (i = 0 ;i < dtp->namelist_name_len ;i++ )
+  for (gfc_charlen_type i = 0; i < dtp->namelist_name_len; i++ )
     {
       c = toupper ((int) dtp->namelist_name[i]);
       write_character (dtp, &c, 1 ,1, NODELIM);
diff --git a/libgfortran/libgfortran.h b/libgfortran/libgfortran.h
index 6243a359dba..84df19e3c6f 100644
--- a/libgfortran/libgfortran.h
+++ b/libgfortran/libgfortran.h
@@ -255,7 +255,7 @@ typedef GFC_INTEGER_4 GFC_IO_INT;
 typedef ptrdiff_t index_type;
 
 /* The type used for the lengths of character variables.  */
-typedef GFC_INTEGER_4 gfc_charlen_type;
+typedef size_t gfc_charlen_type;
 
 /* Definitions of CHARACTER data types:
      - CHARACTER(KIND=1) corresponds to the C char type,