[clang] Match against all plugins when parsing microsoft attributes (PR #86426)

[Aaron Ballman via cfe-commits]

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@@ -5061,11 +5061,15 @@ void Parser::ParseMicrosoftAttributes(ParsedAttributes &Attrs) {
         IdentifierInfo *II = Tok.getIdentifierInfo();
         SourceLocation NameLoc = Tok.getLocation();
         ConsumeToken();
-        ParsedAttr::Kind AttrKind =
-            ParsedAttr::getParsedKind(II, nullptr, ParsedAttr::AS_Microsoft);
+
         // For HLSL we want to handle all attributes, but for MSVC compat, we
         // silently ignore unknown Microsoft attributes.
-        if (getLangOpts().HLSL || AttrKind != ParsedAttr::UnknownAttribute) {
+        AttributeCommonInfo Info{II, NameLoc,
+                                 AttributeCommonInfo::Form::Microsoft()};
+        const ParsedAttrInfo &AttrInfo = ParsedAttrInfo::get(Info);
+        if (getLangOpts().HLSL ||
+            AttrInfo.hasSpelling(AttributeCommonInfo::AS_Microsoft,
+                                 II->getName())) {
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AaronBallman wrote:

Yeah, something seems off here. If the plugin registers the attribute properly, I think the attribute kind won't be `UnknownAttribute` (IIRC it defaults to `NoSemaHandlerAttribute` unless you specify your own kind) so I would have expected to enter this block anyway.

https://github.com/llvm/llvm-project/pull/86426