[clang] Fix crash on broken parameter declarators

[hokein]

Thanks!

clang/test/Parser/cxx-decltype-parameter.cpp

1

I'd place this test in Parser/cxx-keyword-identifiers.cpp since the crash is in the relevant code path.

5

this can be simplified further: void bar(*decltype(1) aux);

clang/lib/Parse/ParseDecl.cpp

if (DS.isEmpty() && ParmDeclarator.getIdentifier() == nullptr &&
       // And we can't handle this in ParseDeclarator because in general keywords
       // may be allowed to follow the declarator. (And in some cases there'd be
       // better recovery like inserting punctuation). ParseDeclarator is just
       // treating this as an anonymous parameter, and fortunately at this point
       // we've already almost done that.
       //
       // We care about case 1) where the declarator type should be known, and
       // the identifier should be null.
-      if (!ParmDeclarator.isInvalidType() && !ParmDeclarator.hasName()) {
-        if (Tok.getIdentifierInfo() &&
-            Tok.getIdentifierInfo()->isKeyword(getLangOpts())) {
-          Diag(Tok, diag::err_keyword_as_parameter) << PP.getSpelling(Tok);
-          // Consume the keyword.
-          ConsumeToken();
-        }
-      }
+      if (!ParmDeclarator.isInvalidType() && !ParmDeclarator.hasName() &&
+          Tok.isNot(tok::raw_identifier) && !Tok.isAnnotation() &&
+          Tok.getIdentifierInfo() &&
       // Inform the actions module about the parameter declarator, so it gets
       // added to the current scope.
       Decl *Param = Actions.ActOnParamDeclarator(getCurScope(), ParmDeclarator);
       // Parse the default argument, if any. We parse the default
       // arguments in all dialects; the semantic analysis in
       // ActOnParamDefaultArgument will reject the default argument in
       // C.
       if (Tok.is(tok::equal)) {

clang/test/Parser/cxx-decltype-parameter.cpp

+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+struct Bar {};
+struct Foo {
+  Bar bar(*decltype(Bar{}) aux); // expected-error {{C++ requires a type specifier for all declarations}}. \
+                                 // expected-error {{expected ')'}} expected-note {{to match this '('}}
+};