Reinstate r104117, Chandler Carruth's change that "[provides] a naming

class for UnresolvedLookupExprs, even when occuring on template
names" along with a fix for an Objective-C++ crasher it introduced.

llvm-svn: 104277

1 files changed, 6 insertions, 11 deletions

diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 320b24227ad..9d8fe9c85f0 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -1079,17 +1079,12 @@ Sema::OwningExprResult Sema::ActOnIdExpression(Scope *S,
   // Perform the required lookup.
   LookupResult R(*this, Name, NameLoc, LookupOrdinaryName);
   if (TemplateArgs) {
-    // Just re-use the lookup done by isTemplateName.
-    DecomposeTemplateName(R, Id);
-
-    // Re-derive the naming class.
-    if (SS.isSet()) {
-      NestedNameSpecifier *Qualifier
-        = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
-      if (const Type *Ty = Qualifier->getAsType())
-        if (CXXRecordDecl *NamingClass = Ty->getAsCXXRecordDecl())
-          R.setNamingClass(NamingClass);
-    }
+    // Lookup the template name again to correctly establish the context in
+    // which it was found. This is really unfortunate as we already did the
+    // lookup to determine that it was a template name in the first place. If
+    // this becomes a performance hit, we can work harder to preserve those
+    // results until we get here but it's likely not worth it.
+    LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false);
   } else {
     bool IvarLookupFollowUp = (!SS.isSet() && II && getCurMethodDecl());
     LookupParsedName(R, S, &SS, !IvarLookupFollowUp);