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 #define MOZ_NONHEAP_CLASS __attribute__((annotate("moz_nonheap_class")))

 #define MOZ_HEAP_ALLOCATOR \

   _Pragma("GCC diagnostic push") \

   _Pragma("GCC diagnostic ignored \"-Wgcc-compat\"") \

   __attribute__((annotate("moz_heap_allocator"))) \

   _Pragma("GCC diagnostic pop")

 #include <stdlib.h>

 #include <memory>

 struct MOZ_NONHEAP_CLASS X {

 };

 void *operator new(size_t x, int qual) MOZ_HEAP_ALLOCATOR {

   return ::operator new(x);

 }

 template <typename T>

 T *customAlloc() MOZ_HEAP_ALLOCATOR {

   T *arg =  static_cast<T*>(malloc(sizeof(T)));

   return new (arg) T();

 }

 template <typename T>

 void misuseX(T q) {

   X *foo = customAlloc<X>(); // expected-error {{variable of type 'X' is not valid on the heap}}

   X *foo2 = new (100) X(); // expected-error {{variable of type 'X' is not valid on the heap}}

 }