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From: "myriachan at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/94554] New: spurious -Waddress warning within "if constexpr" function-null compares Date: Fri, 10 Apr 2020 18:58:47 +0000 [thread overview] Message-ID: <bug-94554-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94554 Bug ID: 94554 Summary: spurious -Waddress warning within "if constexpr" function-null compares Product: gcc Version: 10.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: myriachan at gmail dot com Target Milestone: --- The following with -std=c++17 -Waddress: int meow() { return 1; } void kitty(int); template <int (*F)()> void test() { if constexpr (F) { kitty(F()); } else { kitty(2); } } template void test<nullptr>(); template void test<meow>(); gives a spurious/pointless warning: <source>: In instantiation of 'void test() [with int (* F)() = meow]': <source>:12:26: required from here <source>:5:5: warning: the address of 'int meow()' will never be NULL [-Waddress] 5 | if constexpr (F) { | ^~ The warning should be suppressed in "if constexpr" contexts, because of course it's going to be always true or always false. Clang errors on this case, so it's possible that my code is invalid: Is it legal to compare a function pointer against null in a constant-expression?
next reply other threads:[~2020-04-10 18:58 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-04-10 18:58 myriachan at gmail dot com [this message] 2020-04-10 20:20 ` [Bug c++/94554] " mpolacek at gcc dot gnu.org 2020-04-10 20:22 ` myriachan at gmail dot com 2020-04-14 21:56 ` daniel.kruegler at googlemail dot com 2020-07-10 15:13 ` lts-rudolph at gmx dot de 2020-10-01 17:54 ` mail at 3v1n0 dot net 2022-06-23 4:25 ` jason at gcc dot gnu.org 2022-06-23 4:31 ` jason at gcc dot gnu.org 2022-06-23 15:08 ` cvs-commit at gcc dot gnu.org 2022-06-23 15:44 ` jason at gcc dot gnu.org
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