https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78305
Bug ID: 78305 Summary: Wrong constant folding Product: gcc Version: 7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: ishiura-compiler at ml dot kwansei.ac.jp Target Milestone: --- GCC 7.0.0 for x86_64 miscompiles the following code. % cat test.c int main (void) { int a = 2; int b = 1; int t = -1 * ( -0x40000000 * a / ( -0x20000000 + b ) ) / -1; if (t != 4) __builtin_abort(); return 0; } % gcc-7.0 test.c % ./a.out zsh: abort (core dumped) ./a.out % gcc-7.0 -v Using built-in specs. COLLECT_GCC=gcc-7.0 COLLECT_LTO_WRAPPER=/home/cappie/opt/gcc-7.0.0/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../configure --prefix=/home/cappie/opt/gcc-7.0.0 --disable-nls --disable-multilib --program-suffix=-7.0 --enable-languages=c Thread model: posix gcc version 7.0.0 20161108 (experimental) (GCC)