http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57876
Bug ID: 57876 Summary: wrong code at -O3 on x86_64-linux-gnu in 32-bit mode Product: gcc Version: 4.9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: su at cs dot ucdavis.edu The current gcc trunk mis-compiles the following code on x86_64-linux at -O3 in 32-bit mode. This is a regression from 4.8.x. $ gcc-trunk -v gcc version 4.9.0 20130710 (experimental) [trunk revision 200864] (GCC) $ $ gcc-trunk -m32 -O3 small.c $ a.out 0 $ gcc-trunk -m32 -O2 small.c $ a.out 1 $ gcc-4.8 -m32 -O3 small.c $ a.out 1 $ ---------------------------------------------------- int printf (const char *, ...); int a, b = 1, c, *d = &c, f, *g, h, j; static int e; int main () { int i; for (i = 0; i < 2; i++) { long long k = b; int l; for (f = 0; f < 8; f++) { int *m = &e; j = *d; h = a * j - 1; *m = (h == 0) < k; g = &l; } } printf ("%d\n", e); return 0; }