public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "jwzeng at nuaa dot edu.cn" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/112344] New: [14 Regression] Wrong code at -O2 on x86_64-pc-linux-gnu Date: Thu, 02 Nov 2023 06:30:44 +0000 [thread overview] Message-ID: <bug-112344-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112344 Bug ID: 112344 Summary: [14 Regression] Wrong code at -O2 on x86_64-pc-linux-gnu Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: jwzeng at nuaa dot edu.cn Target Milestone: --- I compiled the following code with gcc at -O2, and it produces the wrong code. The correct output result should be 13, but 73 was output under -O2. This bug seems to only exist on gcc-trunk. The gcc-tk used below is the earliest version I can use that triggers this bug. Compiler explorer: https://godbolt.org/z/8hq64asT5 ```c $ cat test.c int printf(const char *, ...); int a; void b() { long c = 3; unsigned int d = 50253292; int e = 2147483648; for (; a < 5; a++) do { e += 4; d -= c; } while (e < 20); printf("%d\n", d); } int main() { b(); } $ $ gcc-tk test.c -O2; ./test.c 73 $ $ gcc-tk test.c -O0; ./test.c 13 $ gcc-tk test.c -O1; ./test.c 13 $ gcc-tk test.c -O3; ./test.c 13 $ gcc-tk test.c -Os; ./test.c 13 $ ccomp test.c -O1; ./a.out 13 $ $ gcc-tk --version gcc (GCC) 14.0.0 20230922 (experimental) [master r14-4213-gd35e12e1c0] Copyright (C) 2023 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ $ ccomp --version The CompCert C verified compiler, version 3.12 ```
next reply other threads:[~2023-11-02 6:30 UTC|newest] Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-11-02 6:30 jwzeng at nuaa dot edu.cn [this message] 2023-11-02 6:41 ` [Bug middle-end/112344] " pinskia at gcc dot gnu.org 2023-11-02 6:42 ` pinskia at gcc dot gnu.org 2023-11-02 6:47 ` jwzeng at nuaa dot edu.cn 2023-11-02 6:49 ` pinskia at gcc dot gnu.org 2023-11-02 10:06 ` rguenth at gcc dot gnu.org 2023-11-21 19:22 ` jakub at gcc dot gnu.org 2023-11-21 19:23 ` jakub at gcc dot gnu.org 2023-11-22 7:43 ` rguenth at gcc dot gnu.org 2023-11-22 9:10 ` rguenth at gcc dot gnu.org 2023-11-22 10:06 ` rguenth at gcc dot gnu.org 2023-11-22 14:40 ` cvs-commit at gcc dot gnu.org 2023-11-22 14:41 ` rguenth at gcc dot gnu.org 2023-11-24 7:50 ` cvs-commit at gcc dot gnu.org 2024-02-18 10:07 ` cvs-commit at gcc dot gnu.org
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=bug-112344-4@http.gcc.gnu.org/bugzilla/ \ --to=gcc-bugzilla@gcc.gnu.org \ --cc=gcc-bugs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).