From 422bae76c7900101427e05895f315c1d22a237a5 Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Sun, 18 Apr 2010 04:59:38 +0000
Subject: [PATCH] Allow the 'ibaction' attribute to be attached to method
 declarations (and not issue a warning).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@101699 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaDeclObjC.cpp | 14 ++++++++++++--
 test/SemaObjC/ibaction.m  | 15 +++++++++++++++
 2 files changed, 27 insertions(+), 2 deletions(-)
 create mode 100644 test/SemaObjC/ibaction.m

diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index ba6c8bb886..cc1aab4d89 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -1492,6 +1492,16 @@ CvtQTToAstBitMask(ObjCDeclSpec::ObjCDeclQualifier PQTVal) {
   return ret;
 }
 
+static inline
+bool containsInvalidMethodImplAttribute(const AttributeList *A) {
+  // The 'ibaction' attribute is allowed on method definitions because of
+  // how the IBAction macro is used on both method declarations and definitions.
+  // If the method definitions contains any other attributes, return true.
+  while (A && A->getKind() == AttributeList::AT_IBAction)
+    A = A->getNext();
+  return A != NULL;
+}
+
 Sema::DeclPtrTy Sema::ActOnMethodDeclaration(
     SourceLocation MethodLoc, SourceLocation EndLoc,
     tok::TokenKind MethodType, DeclPtrTy classDecl,
@@ -1618,7 +1628,7 @@ Sema::DeclPtrTy Sema::ActOnMethodDeclaration(
     }
     InterfaceMD = ImpDecl->getClassInterface()->getMethod(Sel,
                                                    MethodType == tok::minus);
-    if (AttrList)
+    if (containsInvalidMethodImplAttribute(AttrList))
       Diag(EndLoc, diag::warn_attribute_method_def);
   } else if (ObjCCategoryImplDecl *CatImpDecl =
              dyn_cast<ObjCCategoryImplDecl>(ClassDecl)) {
@@ -1629,7 +1639,7 @@ Sema::DeclPtrTy Sema::ActOnMethodDeclaration(
       PrevMethod = CatImpDecl->getClassMethod(Sel);
       CatImpDecl->addClassMethod(ObjCMethod);
     }
-    if (AttrList)
+    if (containsInvalidMethodImplAttribute(AttrList))
       Diag(EndLoc, diag::warn_attribute_method_def);
   }
   if (PrevMethod) {
diff --git a/test/SemaObjC/ibaction.m b/test/SemaObjC/ibaction.m
new file mode 100644
index 0000000000..b97e002833
--- /dev/null
+++ b/test/SemaObjC/ibaction.m
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 %s -verify
+
+@interface Foo 
+{
+  __attribute__((iboutlet)) id myoutlet;
+}
+- (void) __attribute__((ibaction)) myMessage:(id)msg;
+@end
+
+@implementation Foo
+// Normally attributes should not be attached to method definitions, but
+// we allow 'ibaction' to be attached because it can be expanded from
+// the IBAction macro.
+- (void) __attribute__((ibaction)) myMessage:(id)msg {} // no-warning
+@end
-- 
2.40.0