Fix crash when clang tries to build NSNumber literal after forward declaration

Bug report: http://llvm.org/bugs/show_bug.cgi?id=22561

Clang tries to create ObjCBoxedExpression of type 'NSNumber'
when 'NSNumber' has only forward declaration, this cause a crash later, 
when 'Sema' refers to a nil QualType of the whole expression.
Please, refer to the bug report for the better explanation.

llvm-svn: 229402

1 files changed, 3 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaExprObjC.cpp b/clang/lib/Sema/SemaExprObjC.cpp
index 8bdd18ea20e..cb1f21acac8 100644
--- a/clang/lib/Sema/SemaExprObjC.cpp
+++ b/clang/lib/Sema/SemaExprObjC.cpp
@@ -218,7 +218,9 @@ static ObjCMethodDecl *getNSNumberFactoryMethod(Sema &S, SourceLocation Loc,
       S.Diag(Loc, diag::err_undeclared_nsnumber);
       return nullptr;
     }
-    
+  }
+
+  if (S.NSNumberPointer.isNull()) {
     // generate the pointer to NSNumber type.
     QualType NSNumberObject = CX.getObjCInterfaceType(S.NSNumberDecl);
     S.NSNumberPointer = CX.getObjCObjectPointerType(NSNumberObject);