Index: cfe/trunk/include/clang/Basic/Attr.td
===================================================================
--- cfe/trunk/include/clang/Basic/Attr.td
+++ cfe/trunk/include/clang/Basic/Attr.td
@@ -2138,7 +2138,7 @@
   let TemplateDependent = 1;
   let ParseArgumentsAsUnevaluated = 1;
   let DuplicatesAllowedWhileMerging = 1;
-  let Args = [ExprArgument<"Expr">];
+  let Args = [VariadicExprArgument<"Args">];
   let Accessors = [Accessor<"isShared",
                     [GNU<"assert_shared_capability">,
                      CXX11<"clang", "assert_shared_capability">]>];
Index: cfe/trunk/lib/Analysis/ThreadSafety.cpp
===================================================================
--- cfe/trunk/lib/Analysis/ThreadSafety.cpp
+++ cfe/trunk/lib/Analysis/ThreadSafety.cpp
@@ -1735,8 +1735,23 @@
         CapExprSet AssertLocks;
         Analyzer->getMutexIDs(AssertLocks, A, Exp, D, VD);
         for (const auto &AssertLock : AssertLocks)
-          Analyzer->addLock(FSet, llvm::make_unique<LockableFactEntry>(
-                                      AssertLock, LK_Shared, Loc, false, true),
+          Analyzer->addLock(FSet,
+                            llvm::make_unique<LockableFactEntry>(
+                                AssertLock, LK_Shared, Loc, false, true),
+                            ClassifyDiagnostic(A));
+        break;
+      }
+
+      case attr::AssertCapability: {
+        AssertCapabilityAttr *A = cast<AssertCapabilityAttr>(At);
+        CapExprSet AssertLocks;
+        Analyzer->getMutexIDs(AssertLocks, A, Exp, D, VD);
+        for (const auto &AssertLock : AssertLocks)
+          Analyzer->addLock(FSet,
+                            llvm::make_unique<LockableFactEntry>(
+                                AssertLock,
+                                A->isShared() ? LK_Shared : LK_Exclusive, Loc,
+                                false, true),
                             ClassifyDiagnostic(A));
         break;
       }
Index: cfe/trunk/lib/Sema/SemaDeclAttr.cpp
===================================================================
--- cfe/trunk/lib/Sema/SemaDeclAttr.cpp
+++ cfe/trunk/lib/Sema/SemaDeclAttr.cpp
@@ -5700,8 +5700,12 @@
 
 static void handleAssertCapabilityAttr(Sema &S, Decl *D,
                                        const AttributeList &Attr) {
+  SmallVector<Expr*, 1> Args;
+  if (!checkLockFunAttrCommon(S, D, Attr, Args))
+    return;
+
   D->addAttr(::new (S.Context) AssertCapabilityAttr(Attr.getRange(), S.Context,
-                                                    Attr.getArgAsExpr(0),
+                                                    Args.data(), Args.size(),
                                         Attr.getAttributeSpellingListIndex()));
 }
 
Index: cfe/trunk/test/Sema/attr-capabilities.c
===================================================================
--- cfe/trunk/test/Sema/attr-capabilities.c
+++ cfe/trunk/test/Sema/attr-capabilities.c
@@ -37,9 +37,6 @@
 void Func7(void) __attribute__((assert_capability(GUI))) {}
 void Func8(void) __attribute__((assert_shared_capability(GUI))) {}
 
-void Func9(void) __attribute__((assert_capability())) {} // expected-error {{'assert_capability' attribute takes one argument}}
-void Func10(void) __attribute__((assert_shared_capability())) {} // expected-error {{'assert_shared_capability' attribute takes one argument}}
-
 void Func11(void) __attribute__((acquire_capability(GUI))) {}
 void Func12(void) __attribute__((acquire_shared_capability(GUI))) {}
 
Index: cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp
===================================================================
--- cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp
+++ cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wthread-safety -Wthread-safety-beta -Wno-thread-safety-negative -fcxx-exceptions %s
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wthread-safety -Wthread-safety-beta -Wno-thread-safety-negative -fcxx-exceptions -DUSE_ASSERT_CAPABILITY=0 %s
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 -Wthread-safety -Wthread-safety-beta -Wno-thread-safety-negative -fcxx-exceptions -DUSE_ASSERT_CAPABILITY=1 %s
 
 // FIXME: should also run  %clang_cc1 -fsyntax-only -verify -Wthread-safety -std=c++11 -Wc++98-compat %s
 // FIXME: should also run  %clang_cc1 -fsyntax-only -verify -Wthread-safety %s
@@ -13,8 +14,15 @@
 #define ACQUIRED_BEFORE(...) __attribute__((acquired_before(__VA_ARGS__)))
 #define EXCLUSIVE_LOCK_FUNCTION(...)    __attribute__((exclusive_lock_function(__VA_ARGS__)))
 #define SHARED_LOCK_FUNCTION(...)       __attribute__((shared_lock_function(__VA_ARGS__)))
+
+#if USE_ASSERT_CAPABILITY
+#define ASSERT_EXCLUSIVE_LOCK(...)      __attribute__((assert_capability(__VA_ARGS__)))
+#define ASSERT_SHARED_LOCK(...)         __attribute__((assert_shared_capability(__VA_ARGS__)))
+#else
 #define ASSERT_EXCLUSIVE_LOCK(...)      __attribute__((assert_exclusive_lock(__VA_ARGS__)))
 #define ASSERT_SHARED_LOCK(...)         __attribute__((assert_shared_lock(__VA_ARGS__)))
+#endif
+
 #define EXCLUSIVE_TRYLOCK_FUNCTION(...) __attribute__((exclusive_trylock_function(__VA_ARGS__)))
 #define SHARED_TRYLOCK_FUNCTION(...)    __attribute__((shared_trylock_function(__VA_ARGS__)))
 #define UNLOCK_FUNCTION(...)            __attribute__((unlock_function(__VA_ARGS__)))
@@ -3675,9 +3683,14 @@
                        SHARED_TRYLOCK_FUNCTION(true, mu2_);
   void assertBoth() ASSERT_EXCLUSIVE_LOCK(mu1_)
                     ASSERT_EXCLUSIVE_LOCK(mu2_);
+
+  void alsoAssertBoth() ASSERT_EXCLUSIVE_LOCK(mu1_, mu2_);
+
   void assertShared() ASSERT_SHARED_LOCK(mu1_)
                       ASSERT_SHARED_LOCK(mu2_);
 
+  void alsoAssertShared() ASSERT_SHARED_LOCK(mu1_, mu2_);
+
   void test();
   void testAssert();
   void testAssertShared();
@@ -3741,17 +3754,33 @@
 
 // Force duplication of attributes
 void Foo::assertBoth() { }
+void Foo::alsoAssertBoth() { }
 void Foo::assertShared() { }
+void Foo::alsoAssertShared() { }
 
 void Foo::testAssert() {
-  assertBoth();
-  a = 0;
-  b = 0;
+  {
+    assertBoth();
+    a = 0;
+    b = 0;
+  }
+  {
+    alsoAssertBoth();
+    a = 0;
+    b = 0;
+  }
 }
 
 void Foo::testAssertShared() {
-  assertShared();
-  int zz = a + b;
+  {
+    assertShared();
+    int zz = a + b;
+  }
+
+  {
+    alsoAssertShared();
+    int zz = a + b;
+  }
 }