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From: "shaohua.li at inf dot ethz.ch" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/107293] New: Wrong code at -Os on x86_64-linux-gnu Date: Mon, 17 Oct 2022 12:06:09 +0000 [thread overview] Message-ID: <bug-107293-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107293 Bug ID: 107293 Summary: Wrong code at -Os on x86_64-linux-gnu Product: gcc Version: 13.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: shaohua.li at inf dot ethz.ch Target Milestone: --- % gcc-tk -v Using built-in specs. COLLECT_GCC=gcc-tk COLLECT_LTO_WRAPPER=/zdata/shaoli/compilers/ccbuilder-compilers/gcc-acdb24166d13d87c374e578d2ad5d58249171930/libexec/gcc/x86_64-pc-linux-gnu/13.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../configure --disable-multilib --disable-bootstrap --enable-languages=c,c++ --prefix=/zdata/shaoli/compilers/ccbuilder-compilers/gcc-acdb24166d13d87c374e578d2ad5d58249171930 Thread model: posix Supported LTO compression algorithms: zlib gcc version 13.0.0 20221017 (experimental) (GCC) % % gcc-tk -w -O0 a.c && ./a.out 1 % gcc-tk -w -Os a.c && ./a.out 0 % cat a.c short a; int b[1]; int c(int p) { return (p < 0) ? 0 : 10 + ((p / 100 - 16) / 4); } void f(int n) { while (1) { int m = n; while ((m ) ) m /= 2; break; } } void g() { int h = a = 0; for (; h + a <= 0; a++) { if (b[c(a - 6)]) break; f(a); } } int main() { g(); __builtin_printf("%d\n", a); } % Compiler explorer: https://godbolt.org/z/e7sssT7cq
next reply other threads:[~2022-10-17 12:06 UTC|newest] Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-10-17 12:06 shaohua.li at inf dot ethz.ch [this message] 2022-10-17 12:11 ` [Bug tree-optimization/107293] Wrong code at -Os on x86_64-linux-gnu since r13-2876-g2460f7cdef7ef9c9 marxin at gcc dot gnu.org 2022-10-17 12:47 ` rguenth at gcc dot gnu.org 2022-10-17 16:59 ` aldyh at gcc dot gnu.org 2022-10-17 18:56 ` cvs-commit at gcc dot gnu.org 2022-10-17 18:57 ` aldyh at gcc dot gnu.org 2022-10-21 6:28 ` pinskia at gcc dot gnu.org
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