Fix crash in cleanup attr handling

ResolveSingleFunctionTemplateSpecialization() returns 0 and doesn't emit diags
unless the expression has template-ids, so we must null check the result.

Also add a better diag noting which overloads are causing the problem.

Reviewed by Aaron Ballman.

llvm-svn: 193055

2 files changed, 10 insertions, 2 deletions

diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 3eabf87624c..a71d3c0d7b5 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -2899,10 +2899,15 @@ static void handleCleanupAttr(Sema &S, Decl *D, const AttributeList &Attr) {
   } else if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) {
     if (ULE->hasExplicitTemplateArgs())
       S.Diag(Loc, diag::warn_cleanup_ext);
-
-    // This will diagnose the case where the function cannot be found.
     FD = S.ResolveSingleFunctionTemplateSpecialization(ULE, true);
     NI = ULE->getNameInfo();
+    if (!FD) {
+      S.Diag(Loc, diag::err_attribute_cleanup_arg_not_function) << 2
+        << NI.getName();
+      if (ULE->getType() == S.Context.OverloadTy)
+        S.NoteAllOverloadCandidates(ULE);
+      return;
+    }
   } else {
     S.Diag(Loc, diag::err_attribute_cleanup_arg_not_function) << 0;
     return;
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 6dbb7b6cc57..20cfb00584d 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -9672,6 +9672,9 @@ Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr,
 /// template, where that template-id refers to a single template whose template
 /// arguments are either provided by the template-id or have defaults,
 /// as described in C++0x [temp.arg.explicit]p3.
+///
+/// If no template-ids are found, no diagnostics are emitted and NULL is
+/// returned.
 FunctionDecl *
 Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 
                                                   bool Complain,