https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113026
Bug ID: 113026
Summary: Bogus -Wstringop-overflow warning on simple memcpy
type loop
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: bergner at gcc dot gnu.org
Target Milestone: ---
The following testcase has a bogus warning on trunk back to at least gcc 11.
bergner@ltcden2-lp1:LTC193379$ cat bug.c
char dst[16];
long n = 16;
void
foo (char *src)
{
for (long i = 0; i < n; i++)
dst[i] = src[i];
}
bergner@ltcden2-lp1:LTC193379$ /opt/gcc-nightly/trunk/bin/gcc -S -O3
-mcpu=power8 bug.c
bug.c: In function ‘foo’:
bug.c:8:12: warning: writing 1 byte into a region of size 0
[-Wstringop-overflow=]
8 | dst[i] = src[i];
| ~~~~~~~^~~~~~~~
bug.c:1:6: note: at offset 16 into destination object ‘dst’ of size 16
1 | char dst[16];
| ^~~
bug.c:8:12: warning: writing 1 byte into a region of size 0
[-Wstringop-overflow=]
8 | dst[i] = src[i];
| ~~~~~~~^~~~~~~~
bug.c:1:6: note: at offset 17 into destination object ‘dst’ of size 16
1 | char dst[16];
| ^~~
