[CodeComplete] [clangd] Fix crash on ValueDecl with a null type

Reviewers: kadircet

Reviewed By: kadircet

Subscribers: ioeric, MaskRay, jkorous, arphaman, cfe-commits

Differential Revision: https://reviews.llvm.org/D57093

llvm-svn: 352040
diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index ab18d7f..9bed545 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -680,7 +680,8 @@
     T = Property->getType();
   else if (const auto *Value = dyn_cast<ValueDecl>(ND))
     T = Value->getType();
-  else
+
+  if (T.isNull())
     return QualType();
 
   // Dig through references, function pointers, and block pointers to