Fix crash identified by <rdar://problem/5986085>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@51969 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 102 insertions, 11 deletions

diff --git a/lib/Sema/SemaExprObjC.cpp b/lib/Sema/SemaExprObjC.cpp
index d833efe309..e2e23ce063 100644
--- a/lib/Sema/SemaExprObjC.cpp
+++ b/lib/Sema/SemaExprObjC.cpp
@@ -166,19 +166,31 @@ Sema::ExprResult Sema::ActOnClassMessage(
   } else
     ClassDecl = getObjCInterfaceDecl(receiverName);
   
-  // FIXME: can ClassDecl ever be null?
-  ObjCMethodDecl *Method = ClassDecl->lookupClassMethod(Sel);
+  // ClassDecl is null in the following case.
+  //
+  //  typedef XCElementDisplayRect XCElementGraphicsRect;
+  //
+  //  @implementation XCRASlice
+  //  - whatever { // Note that XCElementGraphicsRect is a typedef name.
+  //    _sGraphicsDelegate =[[XCElementGraphicsRect alloc] init];
+  //  }
+  //
+  // FIXME: Investigate why GCC allows the above.
+  ObjCMethodDecl *Method = 0;
   QualType returnType;
-  
-  // If we have an implementation in scope, check "private" methods.
-  if (!Method) {
-    if (ObjCImplementationDecl *ImpDecl = 
-        ObjCImplementations[ClassDecl->getIdentifier()])
-      Method = ImpDecl->getClassMethod(Sel);
+  if (ClassDecl) {
+    Method = ClassDecl->lookupClassMethod(Sel);
+    
+    // If we have an implementation in scope, check "private" methods.
+    if (!Method) {
+      if (ObjCImplementationDecl *ImpDecl = 
+          ObjCImplementations[ClassDecl->getIdentifier()])
+        Method = ImpDecl->getClassMethod(Sel);
+    }
+    // Before we give up, check if the selector is an instance method.
+    if (!Method)
+      Method = ClassDecl->lookupInstanceMethod(Sel);
   }
-  // Before we give up, check if the selector is an instance method.
-  if (!Method)
-    Method = ClassDecl->lookupInstanceMethod(Sel);
   if (!Method) {
     Diag(lbrac, diag::warn_method_not_found, std::string("+"), Sel.getName(),
          SourceRange(lbrac, rbrac));
diff --git a/test/Sema/objc-typedef-class.m b/test/Sema/objc-typedef-class.m
new file mode 100644
index 0000000000..a35408ba97
--- /dev/null
+++ b/test/Sema/objc-typedef-class.m
@@ -0,0 +1,79 @@
+// RUN: clang -fsyntax-only -verify %s
+typedef signed char BOOL;
+typedef unsigned int NSUInteger;
+typedef struct _NSZone NSZone;
+
+@class NSInvocation, NSMethodSignature, NSCoder, NSString, NSEnumerator;
+
+@protocol NSObject - (BOOL) isEqual:(id) object; @end
+@protocol NSCopying - (id) copyWithZone:(NSZone *) zone; @end
+@protocol NSCoding - (void) encodeWithCoder:(NSCoder *) aCoder; @end
+
+@interface NSObject < NSObject > {}
++(id) alloc;
+@end
+
+typedef float CGFloat;
+
+@interface NSTask:NSObject
+- (id) init;
+@end
+
+typedef NSUInteger NSControlSize;
+typedef struct __CFlags {} _CFlags;
+
+@interface NSCell:NSObject < NSCopying, NSCoding > {}
+@end
+
+@interface NSActionCell:NSCell {} @end
+
+@class NSAttributedString, NSFont, NSImage, NSSound;
+
+typedef struct _XCElementInset {} XCElementInset;
+
+@protocol XCElementP < NSObject >
+-(BOOL) vertical;
+@end
+
+@protocol XCElementDisplayDelegateP;
+@protocol XCElementDisplayDelegateP < NSObject >
+-(void) configureForControlSize:(NSControlSize)size font:(NSFont *)font addDefaultSpace:(XCElementInset) additionalSpace;
+@end
+
+@protocol XCElementSpacerP < XCElementP >
+@end
+
+typedef NSObject < XCElementSpacerP > XCElementSpacer;
+
+@protocol XCElementTogglerP < XCElementP > -(void) setDisplayed:(BOOL) displayed;
+@end
+
+// FIXME: investigate this redefinition error - gcc apparently accepts it.
+typedef NSObject < XCElementTogglerP > XCElementToggler; // expected-error{{previous definition is here}}
+
+@interface XCElementRootFace:NSObject {} @end
+
+@interface XCElementFace:XCElementRootFace {} @end
+
+@class XCElementToggler; // expected-error{{redefinition of 'XCElementToggler' as different kind of symbol}}
+
+@interface XCRASlice:XCElementFace {} @end
+
+@class XCElementSpacings;
+
+@interface XCElementDisplay:NSObject < XCElementDisplayDelegateP > {} @end
+@interface XCElementDisplayRect:XCElementDisplay {} @end
+
+typedef XCElementDisplayRect XCElementGraphicsRect;
+
+@interface XCElementDisplayFillerImage:XCElementDisplay {} @end
+
+@implementation XCRASlice
+- (void) addSliceWithLabel:(NSString *)label statusKey:(NSString *)statusKey disclosed:(BOOL)disclosed
+{
+  static XCElementGraphicsRect *_sGraphicsDelegate = ((void *) 0);
+  if (!_sGraphicsDelegate) {
+    _sGraphicsDelegate =[[XCElementGraphicsRect alloc] init]; // expected-warning{{method '+alloc' not found (return type defaults to 'id')}}
+  }
+}
+@end