From e7300e75b51a7e7d4e81975b4be7a6c65f9a8286 Mon Sep 17 00:00:00 2001 From: Aaron Ballman Date: Wed, 18 Jan 2023 08:49:45 -0500 Subject: Diagnose extensions in 'offsetof' https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2350.htm made very clear that it is an UB having type definitions with in offsetof. Clang supports defining a type as the first argument as a conforming extension due to how many projects use the construct in C99 and earlier to calculate the alignment of a type. GCC also supports defining a type as the first argument. This adds extension warnings and documentation for the functionality Clang explicitly supports. Fixes #57065 Reverts the revert of 39da55e8f548a11f7dadefa73ea73d809a5f1729 Co-authored-by: Yingchi Long Co-authored-by: Aaron Ballman Differential Revision: https://reviews.llvm.org/D133574 --- clang/lib/Parse/ParseDeclCXX.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'clang/lib/Parse/ParseDeclCXX.cpp') diff --git a/clang/lib/Parse/ParseDeclCXX.cpp b/clang/lib/Parse/ParseDeclCXX.cpp index 5d721f4..227c1df 100644 --- a/clang/lib/Parse/ParseDeclCXX.cpp +++ b/clang/lib/Parse/ParseDeclCXX.cpp @@ -2074,7 +2074,7 @@ void Parser::ParseClassSpecifier(tok::TokenKind TagTokKind, DSC == DeclSpecContext::DSC_type_specifier, DSC == DeclSpecContext::DSC_template_param || DSC == DeclSpecContext::DSC_template_type_arg, - &SkipBody); + OffsetOfState, &SkipBody); // If ActOnTag said the type was dependent, try again with the // less common call. -- cgit v1.1