Make PredefinedExpr::ComputeName() more robust to incorrect

code when we are printing the name of an Objective-C method
whose class has not been declared.  Fixes <rdar://problem/7495713>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@98874 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 13 insertions, 1 deletions

diff --git a/lib/AST/Expr.cpp b/lib/AST/Expr.cpp
index a62dbc9012..6a71e925d9 100644
--- a/lib/AST/Expr.cpp
+++ b/lib/AST/Expr.cpp
@@ -227,7 +227,12 @@ std::string PredefinedExpr::ComputeName(IdentType IT, const Decl *CurrentDecl) {
     llvm::raw_svector_ostream Out(Name);
     Out << (MD->isInstanceMethod() ? '-' : '+');
     Out << '[';
-    Out << MD->getClassInterface()->getNameAsString();
+
+    // For incorrect code, there might not be an ObjCInterfaceDecl.  Do
+    // a null check to avoid a crash.
+    if (const ObjCInterfaceDecl *ID = MD->getClassInterface())
+      Out << ID->getNameAsString();
+
     if (const ObjCCategoryImplDecl *CID =
         dyn_cast<ObjCCategoryImplDecl>(MD->getDeclContext())) {
       Out << '(';
diff --git a/test/SemaObjC/invalid-code.m b/test/SemaObjC/invalid-code.m
index 9913a3a237..2f297cf6e6 100644
--- a/test/SemaObjC/invalid-code.m
+++ b/test/SemaObjC/invalid-code.m
@@ -5,3 +5,10 @@ void test1() {
   void *p = @1; // expected-error {{unexpected '@' in program}}
 }
 
+// <rdar://problem/7495713>
+// This previously triggered a crash because the class has not been defined.
+@implementation RDar7495713 (rdar_7495713_cat)  // expected-error{{cannot find interface declaration for 'RDar7495713'}}
+- (id) rdar_7495713 {
+  __PRETTY_FUNCTION__; // expected-warning{{expression result unused}}
+}
+@end