Bug 1209227 - Part 1: Make the MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS analysis handle packs more correctly, r=ehsan

build/clang-plugin/clang-plugin.cpp

@@ -319,6 +319,7 @@ public:
 private:
   bool hasLiteralAnnotation(QualType T) const;
   AnnotationReason directAnnotationReason(QualType T);
+  AnnotationReason tmplArgAnnotationReason(ArrayRef<TemplateArgument> Args);
 
 protected:
   // Allow subclasses to apply annotations to external code:
@@ -882,16 +883,10 @@ CustomTypeAnnotation::directAnnotationReason(QualType T) {
         if (Spec) {
           const TemplateArgumentList &Args = Spec->getTemplateArgs();
 
-          for (const TemplateArgument &Arg : Args.asArray()) {
-            if (Arg.getKind() == TemplateArgument::Type) {
-              QualType Type = Arg.getAsType();
-
-              if (hasEffectiveAnnotation(Type)) {
-                AnnotationReason Reason = {Type, RK_TemplateInherited, nullptr};
-                Cache[Key] = Reason;
-                return Reason;
-              }
-            }
+          AnnotationReason Reason = tmplArgAnnotationReason(Args.asArray());
+          if (Reason.Kind != RK_None) {
+            Cache[Key] = Reason;
+            return Reason;
           }
         }
       }
@@ -903,6 +898,27 @@ CustomTypeAnnotation::directAnnotationReason(QualType T) {
   return Reason;
 }
 
+CustomTypeAnnotation::AnnotationReason
+CustomTypeAnnotation::tmplArgAnnotationReason(ArrayRef<TemplateArgument> Args) {
+  for (const TemplateArgument &Arg : Args) {
+    if (Arg.getKind() == TemplateArgument::Type) {
+      QualType Type = Arg.getAsType();
+      if (hasEffectiveAnnotation(Type)) {
+        AnnotationReason Reason = {Type, RK_TemplateInherited, nullptr};
+        return Reason;
+      }
+    } else if (Arg.getKind() == TemplateArgument::Pack) {
+      AnnotationReason Reason = tmplArgAnnotationReason(Arg.getPackAsArray());
+      if (Reason.Kind != RK_None) {
+        return Reason;
+      }
+    }
+  }
+
+  AnnotationReason Reason = {QualType(), RK_None, nullptr};
+  return Reason;
+}
+
 bool isPlacementNew(const CXXNewExpr *Expr) {
   // Regular new expressions aren't placement new
   if (Expr->getNumPlacementArgs() == 0)

build/clang-plugin/tests/TestInheritTypeAnnotationsFromTemplateArgs.cpp

@@ -25,7 +25,9 @@ static ContainsTemplate e; // expected-error {{variable of type 'ContainsTemplat
 static Template<Normal> f;
 
 template<class T>
-class MOZ_NEEDS_MEMMOVABLE_TYPE Mover { char mForceInstantiation[sizeof(T)]; }; // expected-error-re 5 {{Cannot instantiate 'Mover<{{.*}}>' with non-memmovable template argument '{{.*}}'}}
+class MOZ_NEEDS_MEMMOVABLE_TYPE Mover { // expected-error-re 8 {{Cannot instantiate 'Mover<{{.*}}>' with non-memmovable template argument '{{.*}}'}}
+  char mForceInstantiation[sizeof(T)];
+};
 class IndirectTemplatePointery : Template<Pointery> {}; // expected-note {{'IndirectTemplatePointery' is a non-memmove()able type because it inherits from a non-memmove()able type 'Template<Pointery>'}}
 class ContainsTemplatePointery { Template<Pointery> m; }; // expected-note {{'ContainsTemplatePointery' is a non-memmove()able type because member 'm' is a non-memmove()able type 'Template<Pointery>'}}
 
@@ -35,3 +37,10 @@ static Mover<Template<ContainsPointery>> p; // expected-note {{instantiation of
 static Mover<IndirectTemplatePointery> q; // expected-note {{instantiation of 'Mover<IndirectTemplatePointery>' requested here}}
 static Mover<ContainsTemplatePointery> r; // expected-note {{instantiation of 'Mover<ContainsTemplatePointery>' requested here}}
 static Mover<Template<Normal>> s;
+
+template<class T, class... Ts>
+class MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS ManyTs {}; // expected-note-re 3 {{'ManyTs<{{.*}}>' is a non-memmove()able type because it has a template argument non-memmove()able type '{{.*}}'}}
+
+static Mover<ManyTs<Pointery>> t; // expected-note {{instantiation of 'Mover<ManyTs<Pointery> >' requested here}}
+static Mover<ManyTs<Normal, Pointery>> u; // expected-note {{instantiation of 'Mover<ManyTs<Normal, Pointery> >' requested here}}
+static Mover<ManyTs<Normal, Normal, Pointery>> v; // expected-note {{instantiation of 'Mover<ManyTs<Normal, Normal, Pointery> >' requested here}}