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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug ipa/100994] [12 Regression] wrong code with "-O1 -finline-small-functions -fipa-cp" Date: Wed, 09 Jun 2021 19:02:00 +0000 [thread overview] Message-ID: <bug-100994-4-aLNssWSbu8@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-100994-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100994 --- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Though, SRA isn't really needed, consider following testcase with -O2 -fno-early-inlining -fno-tree-sra -fno-tree-fre struct S { unsigned b : 4; unsigned c : 9; } const d; __attribute__((noipa)) void foo (void) {} static int bar (const struct S l) { ((struct S *)&l)->b += 2; ((struct S *)&l)->c += 4; foo (); return l.b + l.c; } int main () { bar (d); return 0; } This also worked fine with r12-433 and segfaults with r12-434 because it will store to d.b and d.c (instead of modifying an automatic variable). But even if it doesn't bind to a static .rodata variable where stores will segfault, but binds to caller's automatic variable, this binding might change the caller's variable. Perhaps the tree-inline.c change is fine for Ada, but it doesn't seem to be safe for C/C++.
next prev parent reply other threads:[~2021-06-09 19:02 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-06-09 14:29 [Bug ipa/100994] New: " suochenyao at 163 dot com 2021-06-09 18:24 ` [Bug ipa/100994] [12 Regression] " jakub at gcc dot gnu.org 2021-06-09 18:31 ` jakub at gcc dot gnu.org 2021-06-09 18:39 ` jakub at gcc dot gnu.org 2021-06-09 19:02 ` jakub at gcc dot gnu.org [this message] 2021-06-09 19:07 ` jakub at gcc dot gnu.org 2021-06-09 19:41 ` msebor at gcc dot gnu.org 2021-06-09 21:28 ` ebotcazou at gcc dot gnu.org 2021-06-09 21:30 ` ebotcazou at gcc dot gnu.org 2021-06-09 21:32 ` pinskia at gcc dot gnu.org
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