diff options
| author | Richard Biener <rguenther@suse.de> | 2022-06-15 10:54:48 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2022-07-19 11:25:31 +0200 |
| commit | 4f34a9e8d5ffcef99a212180d58718b00bdbb7d2 (patch) | |
| tree | 6b57b1a30275b7b0a5d1be74d469af5529161996 | |
| parent | 1fe7321a6ce0dcb05763c8f1850a066824516342 (diff) | |
tree-optimization/105969 - FPE with array diagnostics
For a [0][0] array we have to be careful when dividing by the element
size which is zero for the outermost dimension. Luckily the division
is only for an overflow check which is pointless for array size zero.
2022-06-15 Richard Biener <rguenther@suse.de>
PR tree-optimization/105969
* gimple-ssa-sprintf.cc (get_origin_and_offset_r): Avoid division
by zero in overflow check.
* gcc.dg/pr105969.c: New testcase.
(cherry picked from commit edb9330c29fe8a0a0b76df6fafd6a223a4d0e41f)
| -rw-r--r-- | gcc/gimple-ssa-sprintf.cc | 2 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr105969.c | 13 |
2 files changed, 14 insertions, 1 deletions
diff --git a/gcc/gimple-ssa-sprintf.cc b/gcc/gimple-ssa-sprintf.cc index 9bd17bcca92..c0405ab32db 100644 --- a/gcc/gimple-ssa-sprintf.cc +++ b/gcc/gimple-ssa-sprintf.cc @@ -2319,7 +2319,7 @@ get_origin_and_offset_r (tree x, HOST_WIDE_INT *fldoff, HOST_WIDE_INT *fldsize, if (byteoff < HOST_WIDE_INT_MAX && elbytes < HOST_WIDE_INT_MAX - && byteoff / elbytes == idx) + && (elbytes == 0 || byteoff / elbytes == idx)) { /* For in-bounds constant offsets into constant-sized arrays bump up *OFF, and for what's likely arrays or structs of diff --git a/gcc/testsuite/gcc.dg/pr105969.c b/gcc/testsuite/gcc.dg/pr105969.c new file mode 100644 index 00000000000..52c63fc2efe --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr105969.c @@ -0,0 +1,13 @@ +/* { dg-do compile } */ +/* { dg-options "-Wall" } */ + +struct A +{ + char a[0][0][0]; +}; +extern struct A b[][2]; +void f (void) +{ + __builtin_sprintf (b[0][0].a[1][0], "%s", b[0][0].a[1][0]); /* { dg-warning "past the end" } */ + /* { dg-warning "overlaps destination" "" { target *-*-* } .-1 } */ +} |