Introduce a centralized routine in Sema for diagnosing failed lookups (when
used as expressions).  In dependent contexts, try to recover by doing a lookup
in previously-dependent base classes.  We get better diagnostics out, but    
unfortunately the recovery fails:  we need to turn it into a method call  
expression, not a bare call expression.  Thus this is still a WIP.

llvm-svn: 91525
diff --git a/clang/test/SemaCXX/conversion-function.cpp b/clang/test/SemaCXX/conversion-function.cpp
index d74bd2e..997e19c 100644
--- a/clang/test/SemaCXX/conversion-function.cpp
+++ b/clang/test/SemaCXX/conversion-function.cpp
@@ -9,7 +9,7 @@
   }
 
   float g() {
-    return operator float(); // expected-error{{no matching function for call to 'operator float'}}
+    return operator float(); // expected-error{{use of undeclared 'operator float'}}
   }
 };