Improve the diagnostic in ARC mode when a conditional with an Objective-C type and void* is used. <rdar://problem/10486347>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151416 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 24 insertions, 0 deletions

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index b961e0961a..7311756de8 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -3622,6 +3622,8 @@ def ext_typecheck_comparison_of_distinct_pointers : ExtWarn<
   "comparison of distinct pointer types (%0 and %1)">;
 def ext_typecheck_cond_incompatible_operands : ExtWarn<
   "incompatible operand types (%0 and %1)">;
+def err_cond_voidptr_arc : Error <
+  "operands to conditional of types %0 and %1 are incompatible in ARC mode">;
 def err_typecheck_comparison_of_distinct_pointers : Error<
   "comparison of distinct pointer types (%0 and %1)">;
 def ext_typecheck_comparison_of_distinct_pointers_nonstandard : ExtWarn<
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 2868b822e6..987ce55c2a 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -4728,6 +4728,14 @@ QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
   }
   // Check Objective-C object pointer types and 'void *'
   if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) {
+    if (getLangOptions().ObjCAutoRefCount) {
+      // ARC forbids the implicit conversion of object pointers to 'void *',
+      // so these types are not compatible.
+      Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
+          << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
+      LHS = RHS = true;
+      return QualType();
+    }
     QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType();
     QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
     QualType destPointee
@@ -4740,6 +4748,14 @@ QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
     return destType;
   }
   if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) {
+    if (getLangOptions().ObjCAutoRefCount) {
+      // ARC forbids the implicit conversion of object pointers to 'void *',
+      // so these types are not compatible.
+      Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
+          << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
+      LHS = RHS = true;
+      return QualType();
+    }
     QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
     QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType();
     QualType destPointee
diff --git a/test/SemaObjC/arc-type-conversion.m b/test/SemaObjC/arc-type-conversion.m
index 8d8ff984fe..5cf2cf4b74 100644
--- a/test/SemaObjC/arc-type-conversion.m
+++ b/test/SemaObjC/arc-type-conversion.m
@@ -90,3 +90,9 @@ void ownership_transfer_in_cast(void *vp, Block *pblk) {
   (void)(Block)&lv; // expected-error {{cast of an indirect pointer to an Objective-C pointer to 'Block'}}
   (void)(Block*)lv; // expected-error {{cast of an Objective-C pointer to '__strong Block *'}}
 }
+
+// <rdar://problem/10486347>
+void conversion_in_conditional(id a, void* b) {
+  id c = 1 ? a : b; // expected-error {{operands to conditional of types 'id' and 'void *' are incompatible in ARC mode}}
+  id d = 1 ? b : a; // expected-error {{operands to conditional of types 'void *' and 'id' are incompatible in ARC mode}}
+}