[clang] [CLANG] Enable alignas after GNU attributes (PR #133107)

[Aaron Ballman via cfe-commits]

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@@ -3035,11 +3035,14 @@ Parser::DeclGroupPtrTy Parser::ParseCXXClassMemberDeclaration(
   }
 
   ParsedAttributes DeclSpecAttrs(AttrFactory);
-  MaybeParseMicrosoftAttributes(DeclSpecAttrs);
-
   // Hold late-parsed attributes so we can attach a Decl to them later.
   LateParsedAttrList CommonLateParsedAttrs;
 
+  while (MaybeParseCXX11Attributes(DeclAttrs) ||
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AaronBallman wrote:

I actually think the `MaybeParseCXX11Attributes()` on line 3007 may be incorrect (a pre-existing bug), because we seem to quietly accept: https://godbolt.org/z/s9qbd8jqn but the grammar for member-declaration does not allow an attribute list to appear there: https://eel.is/c++draft/class#nt:member-declaration

https://github.com/llvm/llvm-project/pull/133107