From: Fariborz Jahanian <fjahanian@apple.com>
Date: Wed, 16 Dec 2009 23:13:33 +0000 (+0000)
Subject: Allow pointer convesion of an objective-c pointer to
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=adcfab1ffcb754672fb943832e04a79593a07a49;p=clang

Allow pointer convesion of an objective-c pointer to
'void *' to mimic gcc's behavior. (fixes radar 7477351).



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@91570 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index a37f86dd34..4565e94ebe 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -915,6 +915,25 @@ BuildSimilarlyQualifiedPointerType(const PointerType *FromPtr,
                                   Quals));
 }
 
+/// BuildSimilarlyQualifiedObjCObjectPointerType - In a pointer conversion from
+/// the FromType, which is an objective-c pointer, to ToType, which may or may
+/// not have the right set of qualifiers.
+static QualType
+BuildSimilarlyQualifiedObjCObjectPointerType(QualType FromType,
+                                             QualType ToType,
+                                             ASTContext &Context) {
+  QualType CanonFromType = Context.getCanonicalType(FromType);
+  QualType CanonToType = Context.getCanonicalType(ToType);
+  Qualifiers Quals = CanonFromType.getQualifiers();
+    
+  // Exact qualifier match -> return the pointer type we're converting to.
+  if (CanonToType.getLocalQualifiers() == Quals)
+    return ToType;
+  
+  // Just build a canonical type that has the right qualifiers.
+  return Context.getQualifiedType(CanonToType.getLocalUnqualifiedType(), Quals);
+}
+  
 static bool isNullPointerConstantForConversion(Expr *Expr,
                                                bool InOverloadResolution,
                                                ASTContext &Context) {
@@ -992,13 +1011,20 @@ bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
     return true;
   }
 
-  // Beyond this point, both types need to be pointers.
+  // Beyond this point, both types need to be pointers 
+  // , including objective-c pointers.
+  QualType ToPointeeType = ToTypePtr->getPointeeType();
+  if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType()) {
+    ConvertedType = BuildSimilarlyQualifiedObjCObjectPointerType(FromType,
+                                                       ToType, Context);
+    return true;
+    
+  }
   const PointerType *FromTypePtr = FromType->getAs<PointerType>();
   if (!FromTypePtr)
     return false;
 
   QualType FromPointeeType = FromTypePtr->getPointeeType();
-  QualType ToPointeeType = ToTypePtr->getPointeeType();
 
   // An rvalue of type "pointer to cv T," where T is an object type,
   // can be converted to an rvalue of type "pointer to cv void" (C++
diff --git a/test/SemaObjCXX/objc-pointer-conv.mm b/test/SemaObjCXX/objc-pointer-conv.mm
new file mode 100644
index 0000000000..c03e3aaad3
--- /dev/null
+++ b/test/SemaObjCXX/objc-pointer-conv.mm
@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+typedef const void * VoidStar;
+
+typedef struct __CFDictionary * CFMDRef;
+
+void RandomFunc(CFMDRef theDict, const void *key, const void *value);
+
+@interface Foo
+- (void)_apply:(void (*)(const void *, const void *, void *))func context:(void *)context;
+- (void)a:(id *)objects b:(id *)keys;
+@end
+
+@implementation Foo
+- (void)_apply:(void (*)(const void *, const void *, void *))func context:(void *)context {
+	id item;
+	id obj;
+    func(item, obj, context);
+}
+
+- (void)a:(id *)objects b:(id *)keys {
+    VoidStar dict;
+	id key;
+    RandomFunc((CFMDRef)dict, key, objects[3]);
+}
+@end