public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "biggs at biggs dot xyz" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/110694] New: False Positive -Werror=free-nonheap-object Date: Mon, 17 Jul 2023 00:54:48 +0000 [thread overview] Message-ID: <bug-110694-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110694 Bug ID: 110694 Summary: False Positive -Werror=free-nonheap-object Product: gcc Version: 13.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: biggs at biggs dot xyz Target Milestone: --- Created attachment 55559 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55559&action=edit Source File Observed on Trunk and 13.1.1 Consider: ```c #include <stdlib.h> typedef struct S S; struct S { int* i; }; static S* s_constructor(void) { S* s = malloc(sizeof(*s)); if (s) s->i = calloc(1, sizeof(*(s->i))); return s; } static void s_destructor(S* s) { if (!s) return; free(s->i); free(s); } static void s_destructor2(S s[static 1]) { free(s->i); free(s); } int main(void) { S* s = s_constructor(); s_destructor(s); s = s_constructor(); if (s) s_destructor2(s); s = (void*) 0; return EXIT_SUCCESS; } ``` Compiling with gcc -Wall -Werror produces the error: <source>: In function 's_destructor2': <source>:23:5: error: 'free' called on unallocated object 's' [-Werror=free-nonheap-object] 23 | free(s); | ^~~~~~~ <source>:21:29: note: declared here 21 | static void s_destructor2(S s[static 1]) { | ~~^~~~~~~~~~~ cc1: all warnings being treated as errors However, there is no error when compiled with -O1 or higher optimization flag. I don't think s_destructor2(S s[static 1]) should emit an error in the first place though. The function definition should be compatible with s_destructor(S* s).
next reply other threads:[~2023-07-17 0:54 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-07-17 0:54 biggs at biggs dot xyz [this message] 2023-07-17 0:59 ` [Bug middle-end/110694] [11/12/13/14 Regression] " pinskia at gcc dot gnu.org 2023-11-01 19:07 ` roman.zilka at gmail dot com 2024-03-07 23:28 ` law 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-110694-4@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).