[PATCH] D97362: [clang][parser] Allow attributes in explicit template instantiations

[Timm Bäder via Phabricator via cfe-commits]

tbaeder added inline comments.


================
Comment at: clang/lib/Parse/ParseDecl.cpp:1618
+
+    if (Tok && (*Tok).is(tok::l_square)) {
+      Diag(Attrs.Range.getBegin(), diag::err_attributes_not_allowed) << Attrs.Range;
----------------
aaron.ballman wrote:
> This will incorrectly classify an empty MS attribute `[]` as being a prohibited `[[]]` attribute. I think we need something like:
> ```
> if (Tok && Tok->is(tok::l_square)) {  
>  SourceLocation NextTokLoc = Lexer::findLocationAfterToken(Attrs.Range.getBegin(), Tok.getKind(), SM, getLangOpts(), true);
>  auto NextTok = Lexer::findNextToken(NextTokLoc, SM, getLangOpts());
>  if (NextTok && NextTok->is(tok::l_square)) {
>    ...
>  }
> }
> ```
> Also, I think it should use `DiagID` rather than hard-coding the diagnostic to use.
The `findNextToken()` here returns the second `[` in `[[]]`, so would return the `]` for `[]`. The code you proposed doesn't work because the second `findNextToken()` returns the first `]`, so not a `tok::l_square`. I know your code makes more sense since we're looking for `[[`, but I couldn't find a way to get the first `[` from the Lexer.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97362/new/

https://reviews.llvm.org/D97362