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From: "bouanto at zoho dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/114768] New: Volatile reads can be optimized away
Date: Thu, 18 Apr 2024 13:19:52 +0000	[thread overview]
Message-ID: <bug-114768-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114768

            Bug ID: 114768
           Summary: Volatile reads can be optimized away
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: bouanto at zoho dot com
  Target Milestone: ---

In the following code:

void test(int *ptr) {
    *ptr = *(volatile int *)ptr;
}

The volatile read is optimized away and GCC produces the following asm:

test(int*):
        ret

Godbolt link: https://gcc.godbolt.org/z/rabToGfqj

Clang produces the following code:

test(int*):                              # @test(int*)
        mov     eax, dword ptr [rdi]
        ret

which is likely to be the expected behavior.

             reply	other threads:[~2024-04-18 13:19 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-18 13:19 bouanto at zoho dot com [this message]
2024-04-18 13:21 ` [Bug rtl-optimization/114768] " rguenth at gcc dot gnu.org
2024-04-18 13:21 ` jakub at gcc dot gnu.org
2024-04-18 13:23 ` rguenth at gcc dot gnu.org
2024-04-18 13:46 ` jakub at gcc dot gnu.org
2024-04-18 13:53 ` segher at gcc dot gnu.org
2024-04-18 13:57 ` segher at gcc dot gnu.org
2024-04-19  6:48 ` cvs-commit at gcc dot gnu.org
2024-04-19  6:49 ` jakub at gcc dot gnu.org
2024-04-19 10:38 ` cvs-commit at gcc dot gnu.org
2024-04-21  4:09 ` cvs-commit at gcc dot gnu.org
2024-04-23  6:43 ` jakub at gcc dot gnu.org
2024-06-11 10:38 ` cvs-commit at gcc dot gnu.org
2024-06-11 10:53 ` jakub at gcc dot gnu.org

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