Ensure Ident_GNU_final is properly initialized in the Parser Initialize function

[erichkeane]

Summary

My recent change to implement __final missed initializing the variable, which was caught by the Memory Sanitizer. This patch properly initializes the value to nullptr to ensure proper memory reads.

[andreybokhanko]

LGTM

I can commit this patch on Monday, when I will reach my work machine.

Andrey

cfe/trunk/lib/Parse/Parser.cpp

if (getLangOpts().ObjC1) {
     ObjCTypeQuals[objc_null_unspecified]
       = &PP.getIdentifierTable().get("null_unspecified");
   }
 
   Ident_instancetype = nullptr;
   Ident_final = nullptr;
   Ident_sealed = nullptr;
   Ident_override = nullptr;
+  Ident_GNU_final = nullptr;
 
   Ident_super = &PP.getIdentifierTable().get("super");
 
   Ident_vector = nullptr;
   Ident_bool = nullptr;
   Ident_pixel = nullptr;
   if (getLangOpts().AltiVec || getLangOpts().ZVector) {
     Ident_vector = &PP.getIdentifierTable().get("vector");