public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "pangbw at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/106818] code is genereated differently with or without 'extern' Date: Fri, 02 Sep 2022 22:29:21 +0000 [thread overview] Message-ID: <bug-106818-4-4W1QzeZCAr@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-106818-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106818 --- Comment #5 from baoshan <pangbw at gmail dot com> --- Per Andrew's request: For GCC built for RISC-V, With the following code: struct sss_t { int i; int j; } sss; extern char array[sizeof(struct sss_t )]; void foo() { struct sss_t *p = (struct sss_t *)array; p->i = 10; } The following asm is generated: foo(): lui a5,%hi(array) li a4,10 sb a4,%lo(array)(a5) sb zero,%lo(array+1)(a5) sb zero,%lo(array+2)(a5) sb zero,%lo(array+3)(a5) ret sss: .zero 8 While if remove the 'extern' from the C code, the following asm is generated: foo(): lui a5,%hi(array) li a4,10 sw a4,%lo(array)(a5) ret array: .zero 8 sss: .zero 8
next prev parent reply other threads:[~2022-09-02 22:29 UTC|newest] Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-09-02 19:26 [Bug c/106818] New: " pangbw at gmail dot com 2022-09-02 19:28 ` [Bug c/106818] " pangbw at gmail dot com 2022-09-02 19:37 ` pinskia at gcc dot gnu.org 2022-09-02 19:38 ` [Bug middle-end/106818] " pinskia at gcc dot gnu.org 2022-09-02 20:03 ` palmer at gcc dot gnu.org 2022-09-02 22:29 ` pangbw at gmail dot com [this message] 2022-09-02 22:33 ` pangbw at gmail dot com 2022-09-02 22:37 ` pinskia at gcc dot gnu.org 2022-09-02 23:59 ` palmer at gcc dot gnu.org 2022-09-05 10:15 ` rguenth at gcc dot gnu.org 2022-10-21 16:22 ` pinskia at gcc dot gnu.org 2022-10-21 16:31 ` [Bug target/106818] riscv produces bad low_sum while doing expansion of strict aligned stores/load pinskia at gcc dot gnu.org 2022-10-21 16:33 ` pinskia at gcc dot gnu.org 2023-11-29 18:45 ` pinskia 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-106818-4-4W1QzeZCAr@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).