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From: "msebor at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/104958] New: missing -Wdangling-pointer leaking local address through struct member Date: Wed, 16 Mar 2022 15:56:33 +0000 [thread overview] Message-ID: <bug-104958-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104958 Bug ID: 104958 Summary: missing -Wdangling-pointer leaking local address through struct member Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: msebor at gcc dot gnu.org Target Milestone: --- As discussed in https://gcc.gnu.org/pipermail/gcc-patches/2022-February/590230.html both functions in the following test case leak the address of the local variable to their caller and should trigger a -Wdangling pointer but only one of them does. The patch submitted to implement this missing functionality was deferred until GCC 13: https://gcc.gnu.org/pipermail/gcc-patches/attachments/20220210/2641dce0/attachment-0003.bin $ cat x.c && gcc -S -Wall x.c struct S { void *p; }; void f (struct S *p) { int j; p->p = &j; // -Wdangling-pointer } struct S g (void) { int i; struct S s = { &i }; // missing -Wdangling-pointer return s; } x.c: In function ‘f’: x.c:6:8: warning: storing the address of local variable ‘j’ in ‘*p.p’ [-Wdangling-pointer=] 6 | p->p = &j; // -Wdangling-pointer | ~~~~~^~~~ x.c:5:7: note: ‘j’ declared here 5 | int j; | ^ x.c:5:7: note: ‘p’ declared here
next reply other threads:[~2022-03-16 15:56 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-03-16 15:56 msebor at gcc dot gnu.org [this message] 2022-03-16 15:57 ` [Bug middle-end/104958] " msebor at gcc dot gnu.org 2022-12-11 1:55 ` pinskia at gcc dot gnu.org 2022-12-11 1:56 ` pinskia at gcc dot gnu.org
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