Bug 1185188 - Support multiple clang-plugin annotations; r=ehsan

build/clang-plugin/clang-plugin.cpp

@@ -232,12 +232,17 @@ public:
     TraverseDecl(ctx.getTranslationUnitDecl());
   }
 
-  static bool hasCustomAnnotation(const Decl *d, const char *spelling) {
-    AnnotateAttr *attr = d->getAttr<AnnotateAttr>();
-    if (!attr)
-      return false;
+  static bool hasCustomAnnotation(const Decl *D, const char *Spelling) {
+    iterator_range<specific_attr_iterator<AnnotateAttr> > Attrs =
+      D->specific_attrs<AnnotateAttr>();
 
-    return attr->getAnnotation() == spelling;
+    for (AnnotateAttr *Attr : Attrs) {
+      if (Attr->getAnnotation() == Spelling) {
+        return true;
+      }
+    }
+
+    return false;
   }
 
   void HandleUnusedExprResult(const Stmt *stmt) {

build/clang-plugin/tests/TestMultipleAnnotations.cpp

@@ -0,0 +1,17 @@
+#define MOZ_MUST_USE __attribute__((annotate("moz_must_use")))
+#define MOZ_STACK_CLASS __attribute__((annotate("moz_stack_class")))
+
+class MOZ_MUST_USE MOZ_STACK_CLASS TestClass {};
+
+TestClass foo; // expected-error {{variable of type 'TestClass' only valid on the stack}}
+
+TestClass f()
+{
+  TestClass bar;
+  return bar;
+}
+
+void g()
+{
+  f(); // expected-error {{Unused MOZ_MUST_USE value of type 'TestClass'}}
+}

build/clang-plugin/tests/moz.build

@@ -9,6 +9,7 @@ SOURCES += [
     'TestCustomHeap.cpp',
     'TestExplicitOperatorBool.cpp',
     'TestGlobalClass.cpp',
+    'TestMultipleAnnotations.cpp',
     'TestMustOverride.cpp',
     'TestMustUse.cpp',
     'TestNANTestingExpr.cpp',