[analyzer] Restrict ObjC type inference to methods that have related result type.

This addresses a case when we inline a wrong method due to incorrect
dynamic type inference. Specifically, when user code contains a method from init
family, which creates an instance of another class.

Use hasRelatedResultType() to find out if our inference rules should be triggered.

llvm-svn: 176054

clang/lib/StaticAnalyzer/Checkers/DynamicTypePropagation.cpp

@@ -110,7 +110,9 @@ void DynamicTypePropagation::checkPostCall(const CallEvent &Call,
       return;
 
     ProgramStateRef State = C.getState();
+    const ObjCMethodDecl *D = Msg->getDecl();
     
+    if (D && D->hasRelatedResultType()) {
       switch (Msg->getMethodFamily()) {
       default:
         break;
@@ -141,7 +143,7 @@ void DynamicTypePropagation::checkPostCall(const CallEvent &Call,
         break;
       }
       }
-
+    }
     return;
   }
 

clang/test/Analysis/inlining/ObjCDynTypePopagation.m

@@ -82,3 +82,20 @@ int testDynamicClass(BOOL coin) {
    return [x getZero];
  return 1;
 }
+
+@interface UserClass : NSObject
+- (PublicSubClass2 *) _newPublicSubClass2;
+- (int) getZero;
+- (void) callNew;
+@end
+
+@implementation UserClass
+- (PublicSubClass2 *) _newPublicSubClass2 {
+  return [[PublicSubClass2 alloc] init];
+}
+- (int) getZero { return 5; }
+- (void) callNew {
+  PublicSubClass2 *x = [self _newPublicSubClass2];
+  clang_analyzer_eval([x getZero] == 0); //expected-warning{{TRUE}}
+}
+@end