Bug 1187073 - Use MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS to validate the usage of AlignedStorage2. r=ehsan

--HG--
extra : rebase_source : 43caddb03d8bf630edd6f8f60f5dff0e8890e7b8

mfbt/Alignment.h

@@ -9,6 +9,7 @@
 #ifndef mozilla_Alignment_h
 #define mozilla_Alignment_h
 
+#include "mozilla/Attributes.h"
 #include <stddef.h>
 #include <stdint.h>
 
@@ -122,7 +123,7 @@ struct AlignedStorage
 };
 
 template<typename T>
-struct AlignedStorage2
+struct MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS AlignedStorage2
 {
   union U
   {

mfbt/Attributes.h

@@ -463,6 +463,10 @@
  *   template arguments are required to be safe to move in memory using
  *   memmove().  Passing MOZ_NON_MEMMOVABLE types to these templates is a
  *   compile time error.
+ * MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS: Applies to template class
+ *   declarations where an instance of the template should be considered, for
+ *   static analysis purposes, to inherit any type annotations (such as
+ *   MOZ_MUST_USE and MOZ_STACK_CLASS) from its template arguments.
  */
 #ifdef MOZ_CLANG_PLUGIN
 #  define MOZ_MUST_OVERRIDE __attribute__((annotate("moz_must_override")))
@@ -486,6 +490,8 @@
 #  define MOZ_NEEDS_NO_VTABLE_TYPE __attribute__((annotate("moz_needs_no_vtable_type")))
 #  define MOZ_NON_MEMMOVABLE __attribute__((annotate("moz_non_memmovable")))
 #  define MOZ_NEEDS_MEMMOVABLE_TYPE __attribute__((annotate("moz_needs_memmovable_type")))
+#  define MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS               \
+    __attribute__((annotate("moz_inherit_type_annotations_from_template_args")))
 /*
  * It turns out that clang doesn't like void func() __attribute__ {} without a
  * warning, so use pragmas to disable the warning. This code won't work on GCC
@@ -513,6 +519,7 @@
 #  define MOZ_NEEDS_NO_VTABLE_TYPE /* nothing */
 #  define MOZ_NON_MEMMOVABLE /* nothing */
 #  define MOZ_NEEDS_MEMMOVABLE_TYPE /* nothing */
+#  define MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS /* nothing */
 #endif /* MOZ_CLANG_PLUGIN */
 
 #endif /* __cplusplus */