r311443 - [ObjC] Check written attributes only when synthesizing ambiguous property

[Alex Lorenz via cfe-commits]

Author: arphaman
Date: Tue Aug 22 03:38:07 2017
New Revision: 311443

URL: http://llvm.org/viewvc/llvm-project?rev=311443&view=rev
Log:
[ObjC] Check written attributes only when synthesizing ambiguous property

This commit fixes a bug introduced in r307903. The attribute ambiguity checker
that was introduced in r307903 checked all property attributes, which caused
errors for source-compatible properties, like:

@property (nonatomic, readonly) NSObject *prop;
@property (nonatomic, readwrite) NSObject *prop;

because the readwrite property would get implicit 'strong' attribute. The
ambiguity checker should be concerned about explicitly specified attributes
only.

rdar://33748089

Modified:
    cfe/trunk/lib/Sema/SemaObjCProperty.cpp
    cfe/trunk/test/SemaObjC/arc-property-decl-attrs.m

Modified: cfe/trunk/lib/Sema/SemaObjCProperty.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaObjCProperty.cpp?rev=311443&r1=311442&r2=311443&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaObjCProperty.cpp (original)
+++ cfe/trunk/lib/Sema/SemaObjCProperty.cpp Tue Aug 22 03:38:07 2017
@@ -872,7 +872,7 @@ SelectPropertyForSynthesisFromProtocols(
   }
 
   QualType RHSType = S.Context.getCanonicalType(Property->getType());
-  unsigned OriginalAttributes = Property->getPropertyAttributes();
+  unsigned OriginalAttributes = Property->getPropertyAttributesAsWritten();
   enum MismatchKind {
     IncompatibleType = 0,
     HasNoExpectedAttribute,
@@ -890,7 +890,7 @@ SelectPropertyForSynthesisFromProtocols(
   SmallVector<MismatchingProperty, 4> Mismatches;
   for (ObjCPropertyDecl *Prop : Properties) {
     // Verify the property attributes.
-    unsigned Attr = Prop->getPropertyAttributes();
+    unsigned Attr = Prop->getPropertyAttributesAsWritten();
     if (Attr != OriginalAttributes) {
       auto Diag = [&](bool OriginalHasAttribute, StringRef AttributeName) {
         MismatchKind Kind = OriginalHasAttribute ? HasNoExpectedAttribute

Modified: cfe/trunk/test/SemaObjC/arc-property-decl-attrs.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/arc-property-decl-attrs.m?rev=311443&r1=311442&r2=311443&view=diff
==============================================================================
--- cfe/trunk/test/SemaObjC/arc-property-decl-attrs.m (original)
+++ cfe/trunk/test/SemaObjC/arc-property-decl-attrs.m Tue Aug 22 03:38:07 2017
@@ -225,3 +225,30 @@ __attribute__((objc_root_class))
 @implementation TypeVsSetter
 @synthesize prop; // expected-note {{property synthesized here}}
 @end
+
+ at protocol AutoStrongProp
+
+ at property (nonatomic, readonly) NSObject *prop;
+
+ at end
+
+ at protocol AutoStrongProp_Internal <AutoStrongProp>
+
+// This property gets the 'strong' attribute automatically.
+ at property (nonatomic, readwrite) NSObject *prop;
+
+ at end
+
+ at interface SynthesizeWithImplicitStrongNoError : NSObject <AutoStrongProp>
+ at end
+
+ at interface SynthesizeWithImplicitStrongNoError () <AutoStrongProp_Internal>
+
+ at end
+
+ at implementation SynthesizeWithImplicitStrongNoError
+
+// no error, 'strong' is implicit in the 'readwrite' property.
+ at synthesize prop = _prop;
+
+ at end