public inbox for gcc-cvs@sourceware.org help / color / mirror / Atom feed
From: Richard Biener <rguenth@gcc.gnu.org> To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-7467] middle-end/110055 - avoid CLOBBERing static variables Date: Fri, 23 Jun 2023 10:30:00 +0000 (GMT) [thread overview] Message-ID: <20230623103000.B85C63858421@sourceware.org> (raw) https://gcc.gnu.org/g:b0856bb588c76e16a518b459a8c9a012dc2b4e21 commit r13-7467-gb0856bb588c76e16a518b459a8c9a012dc2b4e21 Author: Richard Biener <rguenther@suse.de> Date: Mon Jun 5 08:56:53 2023 +0200 middle-end/110055 - avoid CLOBBERing static variables The gimplifier can elide initialized constant automatic variables to static storage in which case TARGET_EXPR gimplification needs to avoid emitting a CLOBBER for them since their lifetime is no longer limited. Failing to do so causes spurious dangling-pointer diagnostics on the added testcase for some targets. PR middle-end/110055 * gimplify.cc (gimplify_target_expr): Do not emit CLOBBERs for variables which have static storage duration after gimplifying their initializers. * g++.dg/warn/Wdangling-pointer-pr110055.C: New testcase. (cherry picked from commit 84eec2916fa68cd2e2b3a2cf764f2ba595cce843) Diff: --- gcc/gimplify.cc | 4 +++- gcc/testsuite/g++.dg/warn/Wdangling-pointer-pr110055.C | 16 ++++++++++++++++ 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc index ade6e335da7..aece89a3e9b 100644 --- a/gcc/gimplify.cc +++ b/gcc/gimplify.cc @@ -7154,8 +7154,10 @@ gimplify_target_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p) gimplify_and_add (init, &init_pre_p); /* Add a clobber for the temporary going out of scope, like - gimplify_bind_expr. */ + gimplify_bind_expr. But only if we did not promote the + temporary to static storage. */ if (gimplify_ctxp->in_cleanup_point_expr + && !TREE_STATIC (temp) && needs_to_live_in_memory (temp)) { if (flag_stack_reuse == SR_ALL) diff --git a/gcc/testsuite/g++.dg/warn/Wdangling-pointer-pr110055.C b/gcc/testsuite/g++.dg/warn/Wdangling-pointer-pr110055.C new file mode 100644 index 00000000000..77dbbf380b6 --- /dev/null +++ b/gcc/testsuite/g++.dg/warn/Wdangling-pointer-pr110055.C @@ -0,0 +1,16 @@ +// { dg-do compile } +// { dg-require-effective-target c++11 } +// { dg-options "-O3 -fno-exceptions -Wdangling-pointer" } + +#include <cstdint> +#include <vector> + +struct Data { + std::vector<uint16_t> v = {1, 1}; +}; + +int main() +{ + Data a; + Data b; +}
reply other threads:[~2023-06-23 10:30 UTC|newest] Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=20230623103000.B85C63858421@sourceware.org \ --to=rguenth@gcc.gnu.org \ --cc=gcc-cvs@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).