Using the function pointer instead of the function type; this allows us to re-enable a warning in MSVC by default.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@187292 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Core/MemRegion.cpp b/lib/StaticAnalyzer/Core/MemRegion.cpp
index 3c9e9e4..9051d5a 100644
--- a/lib/StaticAnalyzer/Core/MemRegion.cpp
+++ b/lib/StaticAnalyzer/Core/MemRegion.cpp
@@ -981,7 +981,7 @@
                                          bool IsVirtual) {
   if (isa<TypedValueRegion>(Super)) {
     assert(isValidBaseClass(RD, dyn_cast<TypedValueRegion>(Super), IsVirtual));
-    (void)isValidBaseClass;
+    (void)&isValidBaseClass;
 
     if (IsVirtual) {
       // Virtual base regions should not be layered, since the layout rules