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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/52953] function parameter name redeclarations not detected
Date: Wed, 30 Aug 2023 18:28:20 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D52953

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 55820
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=3D55820&action=3Dedit
gcc14-pr52953-2.patch

Untested incremental patch to diagnose even extern redeclarations in the
https://eel.is/c++draft/basic.scope#block-2 case.
I'm not convinced this second part is correct though and there seems to be
high implementation variance (g++ vs. clang++ vs. ICC vs. MSVC).
Because https://eel.is/c++draft/basic.scope#block-2 talks about declarations
whose target scope is the block scope of S, while
https://eel.is/c++draft/basic.scope#scope-2.10 says that extern block-scope
declarations target larger scope but bind a name in the immediate scope.=