Index: include/clang/Basic/Attr.td
===================================================================
--- include/clang/Basic/Attr.td
+++ include/clang/Basic/Attr.td
@@ -881,6 +881,13 @@
   let Documentation = [Undocumented];
 }
 
+def DisableTailCalls : InheritableAttr {
+  let Spellings = [GNU<"disable_tail_calls">,
+                   CXX11<"clang", "disable_tail_calls">];
+  let Subjects = SubjectList<[Function, ObjCMethod]>;
+  let Documentation = [DisableTailCallsDocs];
+}
+
 def NoAlias : InheritableAttr {
   let Spellings = [Declspec<"noalias">];
   let Subjects = SubjectList<[Function]>;
Index: include/clang/Basic/AttrDocs.td
===================================================================
--- include/clang/Basic/AttrDocs.td
+++ include/clang/Basic/AttrDocs.td
@@ -1612,3 +1612,10 @@
 arguments, with arbitrary offsets.
   }];
 }
+
+def DisableTailCallsDocs : Documentation {
+  let Category = DocCatFunction;
+  let Content = [{
+The ``disable_tail_calls`` attribute instructs the backend to not perform tail call optimization.
+  }];
+}
Index: lib/CodeGen/CGCall.cpp
===================================================================
--- lib/CodeGen/CGCall.cpp
+++ lib/CodeGen/CGCall.cpp
@@ -1480,8 +1480,12 @@
       FuncAttrs.addAttribute("no-frame-pointer-elim-non-leaf");
     }
 
+    bool DisableTailCalls =
+        (TargetDecl && TargetDecl->hasAttr<DisableTailCallsAttr>()) ||
+        CodeGenOpts.DisableTailCalls;
     FuncAttrs.addAttribute("disable-tail-calls",
-                           llvm::toStringRef(CodeGenOpts.DisableTailCalls));
+                           llvm::toStringRef(DisableTailCalls));
+
     FuncAttrs.addAttribute("less-precise-fpmad",
                            llvm::toStringRef(CodeGenOpts.LessPreciseFPMAD));
     FuncAttrs.addAttribute("no-infs-fp-math",
Index: lib/Sema/SemaDeclAttr.cpp
===================================================================
--- lib/Sema/SemaDeclAttr.cpp
+++ lib/Sema/SemaDeclAttr.cpp
@@ -1696,6 +1696,15 @@
                                    Attr.getAttributeSpellingListIndex()));
 }
 
+static void handleDisableTailCallsAttr(Sema &S, Decl *D,
+                                       const AttributeList &Attr) {
+  if (checkAttrMutualExclusion<NakedAttr>(S, D, Attr))
+    return;
+
+  D->addAttr(::new (S.Context) DisableTailCallsAttr(
+      Attr.getRange(), S.Context, Attr.getAttributeSpellingListIndex()));
+}
+
 static void handleUsedAttr(Sema &S, Decl *D, const AttributeList &Attr) {
   if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
     if (VD->hasLocalStorage()) {
@@ -4886,6 +4895,9 @@
   case AttributeList::AT_ReturnsTwice:
     handleSimpleAttribute<ReturnsTwiceAttr>(S, D, Attr);
     break;
+  case AttributeList::AT_DisableTailCalls:
+    handleDisableTailCallsAttr(S, D, Attr);
+    break;
   case AttributeList::AT_Used:
     handleUsedAttr(S, D, Attr);
     break;
Index: test/CodeGen/attr-disable-tail-calls.c
===================================================================
--- test/CodeGen/attr-disable-tail-calls.c
+++ test/CodeGen/attr-disable-tail-calls.c
@@ -1,11 +1,19 @@
-// RUN: %clang_cc1 -triple x86_64-apple-macosx10.7.0 %s -emit-llvm -mdisable-tail-calls -o - | FileCheck %s -check-prefix=CHECK -check-prefix=DISABLE
-// RUN: %clang_cc1 -triple x86_64-apple-macosx10.7.0 %s -emit-llvm -o - | FileCheck %s -check-prefix=CHECK -check-prefix=ENABLE
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.7.0 %s -emit-llvm -mdisable-tail-calls -o - | FileCheck %s -check-prefix=DISABLE
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.7.0 %s -emit-llvm -o - | FileCheck %s -check-prefix=ENABLE
 
-// CHECK: define i32 @f1() [[ATTR:#[0-9]+]] {
+// DISABLE: define i32 @f1() [[ATTRTRUE:#[0-9]+]] {
+// DISABLE: define i32 @f2() [[ATTRTRUE]] {
+// ENABLE: define i32 @f1() [[ATTRFALSE:#[0-9]+]] {
+// ENABLE: define i32 @f2() [[ATTRTRUE:#[0-9]+]] {
 
 int f1() {
   return 0;
 }
 
-// DISABLE: attributes [[ATTR]] = { {{.*}} "disable-tail-calls"="true" {{.*}} }
-// ENABLE: attributes [[ATTR]] = { {{.*}} "disable-tail-calls"="false" {{.*}} }
+int f2() __attribute__((disable_tail_calls)) {
+  return 0;
+}
+
+// DISABLE: attributes [[ATTRTRUE]] = { {{.*}}"disable-tail-calls"="true"{{.*}} }
+// ENABLE: attributes [[ATTRFALSE]] = { {{.*}}"disable-tail-calls"="false"{{.*}} }
+// ENABLE: attributes [[ATTRTRUE]] = { {{.*}}"disable-tail-calls"="true"{{.*}} }
Index: test/Sema/disable-tail-calls-attr.c
===================================================================
--- /dev/null
+++ test/Sema/disable-tail-calls-attr.c
@@ -0,0 +1,5 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+void __attribute__((disable_tail_calls,naked)) foo1(int a) { // expected-error {{'disable_tail_calls' and 'naked' attributes are not compatible}}
+  __asm__("");
+}