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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/109778] New: Wrong code at -O3 on x86_64-linux-gnu since GCC-12.2 Date: Mon, 08 May 2023 19:18:28 +0000 [thread overview] Message-ID: <bug-109778-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109778 Bug ID: 109778 Summary: Wrong code at -O3 on x86_64-linux-gnu since GCC-12.2 Product: gcc Version: 14.0 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 trunk at -O3 emits wrong code. This seems to be a bug since gcc-12.2 Compiler explorer: https://godbolt.org/z/E5aqnMK6Y $ cat a.c int printf(const char *, ...); int a, b, c, d; int *e = &c; unsigned f(unsigned char g) { g = 1 | g << 1; g = g >> 4 | g << 4; return g; } void h(unsigned g) { *e = 8 > f(g + 86) - 86; } int main() { d = a && b; h(d + 4); printf("%d\n", c); } $ $ gcc-tk -O0 a.c && ./a.out 1 $ gcc-tk -O3 a.c && ./a.out 0 $ $ gcc-tk -v Using built-in specs. COLLECT_GCC=gcc-tk COLLECT_LTO_WRAPPER=/zdata/shaoli/compilers/ccbuilder-compilers/gcc-b7fe38c14e5f1bc32950c7b2ffc8537c7c381af4/libexec/gcc/x86_64-pc-linux-gnu/14.0.0/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-b7fe38c14e5f1bc32950c7b2ffc8537c7c381af4 Thread model: posix Supported LTO compression algorithms: zlib gcc version 14.0.0 20230506 (experimental) (GCC) $
next reply other threads:[~2023-05-08 19:18 UTC|newest] Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-05-08 19:18 shaohua.li at inf dot ethz.ch [this message] 2023-05-08 19:30 ` [Bug tree-optimization/109778] [12/13/14 Regression] Wrong code at -O1 and above " pinskia at gcc dot gnu.org 2023-05-08 19:31 ` [Bug tree-optimization/109778] [13/14 Regression] Wrong code at -O1 and above on x86_64-linux-gnu pinskia at gcc dot gnu.org 2023-05-08 19:36 ` jakub at gcc dot gnu.org 2023-05-08 22:09 ` jakub at gcc dot gnu.org 2023-05-09 7:38 ` rguenth at gcc dot gnu.org 2023-05-09 10:11 ` cvs-commit at gcc dot gnu.org 2023-05-09 10:19 ` cvs-commit at gcc dot gnu.org 2023-05-09 10:23 ` [Bug tree-optimization/109778] [10/11/12/13 " jakub at gcc dot gnu.org 2023-05-09 10:49 ` cvs-commit at gcc dot gnu.org 2023-05-09 10:49 ` cvs-commit at gcc dot gnu.org 2023-05-09 10:56 ` cvs-commit at gcc dot gnu.org 2023-05-09 10:56 ` cvs-commit at gcc dot gnu.org 2023-05-09 11:04 ` cvs-commit at gcc dot gnu.org 2023-05-09 11:04 ` cvs-commit at gcc dot gnu.org 2023-05-09 11:10 ` cvs-commit at gcc dot gnu.org 2023-05-09 11:10 ` cvs-commit at gcc dot gnu.org 2023-05-21 16:56 ` jakub at gcc dot gnu.org
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