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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug ipa/103830] [12 Regression] null pointer access optimized away by removing function call at -Og Date: Fri, 28 Jan 2022 12:04:20 +0000 [thread overview] Message-ID: <bug-103830-4-i5pGKLMVRe@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-103830-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103830 --- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> --- A fix in the source would be: void MyClass::call() { volatile char * volatile null = nullptr; *null = 1; /* line 26 */ } which then compiles to movq $0, -8(%rsp) movq -8(%rsp), %rax movb $1, (%rax) ret (some "advanced" means using some asm() to hide the constant from the compiler might also work)
next prev parent reply other threads:[~2022-01-28 12:04 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-12-26 10:00 [Bug rtl-optimization/103830] New: volatile optimized away bernd.edlinger at hotmail dot de 2021-12-26 10:10 ` [Bug rtl-optimization/103830] " pinskia at gcc dot gnu.org 2021-12-26 10:19 ` [Bug ipa/103830] [12 Regression] null pointer access optimized away by removing function call at -Og pinskia at gcc dot gnu.org 2021-12-27 16:20 ` jakub at gcc dot gnu.org 2022-01-04 13:35 ` rguenth at gcc dot gnu.org 2022-01-04 14:52 ` hubicka at kam dot mff.cuni.cz 2022-01-28 12:02 ` rguenth at gcc dot gnu.org 2022-01-28 12:04 ` rguenth at gcc dot gnu.org [this message] 2022-01-28 12:06 ` rguenth at gcc dot gnu.org 2022-01-28 12:08 ` bernd.edlinger at hotmail dot de
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