From accfc00d82627188317a54eb068340bdc3d9e2e8 Mon Sep 17 00:00:00 2001
From: Dulma Churchill <dulmarod@fb.com>
Date: Tue, 15 May 2018 08:50:29 -0700
Subject: [PATCH] [objc frontend] Do not crash on internal forward classes

Reviewed By: mbouaziz

Differential Revision: D8010231

fbshipit-source-id: 2260fa6
---
 infer/src/clang/cFrontend_decl.ml             |  3 +--
 .../ForwardClassInMethod.m                    | 21 +++++++++++++++++++
 .../ForwardClassInMethod.m.dot                | 10 +++++++++
 .../objc/frontend/noarc/Makefile              |  1 +
 4 files changed, 33 insertions(+), 2 deletions(-)
 create mode 100644 infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m
 create mode 100644 infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m.dot

diff --git a/infer/src/clang/cFrontend_decl.ml b/infer/src/clang/cFrontend_decl.ml
index 021a78531..a1b0855a9 100644
--- a/infer/src/clang/cFrontend_decl.ml
+++ b/infer/src/clang/cFrontend_decl.ml
@@ -204,7 +204,7 @@ module CFrontend_decl_funct (T : CModule_type.CTranslation) : CModule_type.CFron
     | ObjCPropertyImplDecl (_, obj_c_property_impl_decl_info) ->
         process_property_implementation trans_unit_ctx tenv cfg curr_class
           obj_c_property_impl_decl_info
-    | EmptyDecl _ | ObjCIvarDecl _ | ObjCPropertyDecl _ ->
+    | EmptyDecl _ | ObjCIvarDecl _ | ObjCPropertyDecl _ | ObjCInterfaceDecl _ ->
         ()
     | AccessSpecDecl _
     | BlockDecl _
@@ -224,7 +224,6 @@ module CFrontend_decl_funct (T : CModule_type.CTranslation) : CModule_type.CFron
     | ObjCCategoryDecl _
     | ObjCCategoryImplDecl _
     | ObjCImplementationDecl _
-    | ObjCInterfaceDecl _
     | ObjCProtocolDecl _
     | BuiltinTemplateDecl _
     | ClassTemplateDecl _
diff --git a/infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m b/infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m
new file mode 100644
index 000000000..d27e5e8be
--- /dev/null
+++ b/infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2018 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+#import <Foundation/NSObject.h>
+
+@interface A : NSObject
+
+@end
+
+@implementation A
+
+- (void)foo {
+}
+@class B;
+
+@end
diff --git a/infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m.dot b/infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m.dot
new file mode 100644
index 000000000..8c4be2d07
--- /dev/null
+++ b/infer/tests/codetoanalyze/objc/frontend/internal_forward_class/ForwardClassInMethod.m.dot
@@ -0,0 +1,10 @@
+/* @generated */
+digraph cfg {
+"foo#A#instance.a1bcc3cb6c1f00fc285817fb8454eaed_1" [label="1: Start A_foo\nFormals:  self:A*\nLocals:  \n   DECLARE_LOCALS(&return); [line 17, column 1]\n " color=yellow style=filled]
+	
+
+	 "foo#A#instance.a1bcc3cb6c1f00fc285817fb8454eaed_1" -> "foo#A#instance.a1bcc3cb6c1f00fc285817fb8454eaed_2" ;
+"foo#A#instance.a1bcc3cb6c1f00fc285817fb8454eaed_2" [label="2: Exit A_foo \n  " color=yellow style=filled]
+	
+
+}
diff --git a/infer/tests/codetoanalyze/objc/frontend/noarc/Makefile b/infer/tests/codetoanalyze/objc/frontend/noarc/Makefile
index a64080bf3..77aefecf9 100644
--- a/infer/tests/codetoanalyze/objc/frontend/noarc/Makefile
+++ b/infer/tests/codetoanalyze/objc/frontend/noarc/Makefile
@@ -27,6 +27,7 @@ SOURCES = \
   ../conditional_operation/ConditionalOperation.m \
   ../exceptions/ExceptionExample.m \
   ../fast_enumeration/Fast_enumeration.m \
+	../internal_forward_class/ForwardClassInMethod.m \
   ../property/PropertyCustomAccessor.m \
   ../property/PropertyImplSetter.m \
   ../property/Property_getter.m \