[PATCH] D133248: [clang] Fix crash upon stray coloncolon token in C2x mode

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman accepted this revision.
aaron.ballman added a comment.
This revision is now accepted and ready to land.

Good catch that this was crashing! LGTM aside from the nit pointed out by @tbaeder. Can you also add a release note for the fix? Do you need someone to commit on your behalf? If so, what name and email address would you like used for patch attribution?



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Comment at: clang/lib/Parse/ParseDecl.cpp:5340
+    if (!getLangOpts().CPlusPlus)
+      return false;
     if (NextToken().is(tok::kw_new) ||    // ::new
----------------
inclyc wrote:
> Maybe we can make a new `error` diagnostic definition and fire that here?
I don't think we should -- this function is used to query whether something is a declaration specifier or not; it'd be surprising to issue a diagnostic from that kind of interface.


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Comment at: clang/test/Parser/c2x-attributes.c:146
+// Ensure that '::' outside of attributes does not crash and is not treated as scope
+double n::v; // expected-error {{expected ';' after top level declarator}}
----------------
inclyc wrote:
> Could we improve this diagnostic message? 
> ```
> expected ';' after top level declarator}
> ```
That might be possible, but it should happen as a separate patch. That said, I'm not certain how much improvement there is to be had there, especially in C mode. It really does look like the user is trying to declare a variable named `n` and got the wrong kind of colon.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D133248/new/

https://reviews.llvm.org/D133248