Parse: Consume tokens more carefully in CheckForLParenAfterColonColon

We would consume the lparen even if it wasn't followed by an identifier
or a star-identifier pair.

This fixes PR21815.

llvm-svn: 224403

1 files changed, 29 insertions, 27 deletions

diff --git a/clang/lib/Parse/ParseExprCXX.cpp b/clang/lib/Parse/ParseExprCXX.cpp
index 613246ef712..dad1f0da2ef 100644
--- a/clang/lib/Parse/ParseExprCXX.cpp
+++ b/clang/lib/Parse/ParseExprCXX.cpp
@@ -108,35 +108,37 @@ void Parser::CheckForLParenAfterColonColon() {
   if (!Tok.is(tok::l_paren))
     return;
 
-  SourceLocation l_parenLoc = ConsumeParen(), r_parenLoc;
-  Token Tok1 = getCurToken();
-  if (!Tok1.is(tok::identifier) && !Tok1.is(tok::star))
+  Token LParen = Tok;
+  Token NextTok = GetLookAheadToken(1);
+  Token StarTok = NextTok;
+  // Check for (identifier or (*identifier
+  Token IdentifierTok = StarTok.is(tok::star) ? GetLookAheadToken(2) : StarTok;
+  if (IdentifierTok.isNot(tok::identifier))
     return;
-
-  if (Tok1.is(tok::identifier)) {
-    Token Tok2 = GetLookAheadToken(1);
-    if (Tok2.is(tok::r_paren)) {
+  // Eat the '('.
+  ConsumeParen();
+  Token RParen;
+  // Do we have a ')' ?
+  NextTok = StarTok.is(tok::star) ? GetLookAheadToken(2) : GetLookAheadToken(1);
+  if (NextTok.is(tok::r_paren)) {
+    RParen = NextTok;
+    // Eat the '*' if it is present.
+    if (StarTok.is(tok::star))
       ConsumeToken();
-      PP.EnterToken(Tok1);
-      r_parenLoc = ConsumeParen();
-    }
-  } else if (Tok1.is(tok::star)) {
-    Token Tok2 = GetLookAheadToken(1);
-    if (Tok2.is(tok::identifier)) {
-      Token Tok3 = GetLookAheadToken(2);
-      if (Tok3.is(tok::r_paren)) {
-        ConsumeToken();
-        ConsumeToken();
-        PP.EnterToken(Tok2);
-        PP.EnterToken(Tok1);
-        r_parenLoc = ConsumeParen();
-      }
-    }
-  }
-
-  Diag(l_parenLoc, diag::err_paren_after_colon_colon)
-      << FixItHint::CreateRemoval(l_parenLoc)
-      << FixItHint::CreateRemoval(r_parenLoc);
+    // Eat the identifier.
+    ConsumeToken();
+    // Add the identifier token back.
+    PP.EnterToken(IdentifierTok);
+    // Add the '*' back if it was present.
+    if (StarTok.is(tok::star))
+      PP.EnterToken(StarTok);
+    // Eat the ')'.
+    ConsumeParen();
+  }
+
+  Diag(LParen.getLocation(), diag::err_paren_after_colon_colon)
+      << FixItHint::CreateRemoval(LParen.getLocation())
+      << FixItHint::CreateRemoval(RParen.getLocation());
 }
 
 /// \brief Parse global scope or nested-name-specifier if present.