Follow-up to r217302 and r227555: Don't crash on inline ~A::A() if A is an int.

Even with r227555, this still crashed:

  struct S {
    int A;
    ~A::A() {}
  };

That's because ParseOptionalCXXScopeSpecifier()'s call to
ActOnCXXNestedNameSpecifier() doesn't mark the scope spec as invalid if sema
thought it's a good idea to fixit-correct "::" to ":".  For the diagnostic
improvement done in r217302, we never want :: to be interpreted as :, so fix
this by setting ColonSacred to false temporarily.

Found by SLi's bot.

llvm-svn: 227581

1 files changed, 7 insertions, 1 deletions

diff --git a/clang/lib/Parse/ParseExprCXX.cpp b/clang/lib/Parse/ParseExprCXX.cpp
index a753b0ff27a..8faec51667b 100644
--- a/clang/lib/Parse/ParseExprCXX.cpp
+++ b/clang/lib/Parse/ParseExprCXX.cpp
@@ -2509,7 +2509,13 @@ bool Parser::ParseUnqualifiedId(CXXScopeSpec &SS, bool EnteringContext,
 
     // If the user wrote ~T::T, correct it to T::~T.
     DeclaratorScopeObj DeclScopeObj(*this, SS);
-    if (!TemplateSpecified && NextToken().is(tok::coloncolon)) {
+    if (!TemplateSpecified && //!ColonIsSacred &&
+        NextToken().is(tok::coloncolon)) {
+      // Don't let ParseOptionalCXXScopeSpecifier() "correct"
+      // `int A; struct { ~A::A(); };` to `int A; struct { ~A:A(); };`,
+      // it will confuse this recovery logic.
+      ColonProtectionRAIIObject ColonRAII(*this, false);
+
       if (SS.isSet()) {
         AnnotateScopeToken(SS, /*NewAnnotation*/true);
         SS.clear();