[libclang] Add defensive checks to make sure we don't try to dereference

a null pointer after getCursorDecl() is called. rdar://10298421.

llvm-svn: 146312

1 files changed, 1 insertions, 2 deletions

diff --git a/clang/tools/libclang/CXCursor.cpp b/clang/tools/libclang/CXCursor.cpp
index 5117a4d2b3e..1b8af395e22 100644
--- a/clang/tools/libclang/CXCursor.cpp
+++ b/clang/tools/libclang/CXCursor.cpp
@@ -1019,8 +1019,7 @@ CXCompletionString clang_getCursorCompletionString(CXCursor cursor) {
   enum CXCursorKind kind = clang_getCursorKind(cursor);
   if (clang_isDeclaration(kind)) {
     Decl *decl = getCursorDecl(cursor);
-    if (isa<NamedDecl>(decl)) {
-      NamedDecl *namedDecl = (NamedDecl *)decl;
+    if (NamedDecl *namedDecl = dyn_cast_or_null<NamedDecl>(decl)) {
       ASTUnit *unit = getCursorASTUnit(cursor);
       if (unit->hasSema()) {
         Sema &S = unit->getSema();