message: libmesh: add mesh_usable_size
diff: @@ -38,6 +38,10 @@ size_t xxmalloc_usable_size(void *ptr) {
  return runtime().localHeap()->getSize(ptr);
  }
  +size_t mesh_usable_size(void *ptr) {
  + return xxmalloc_usable_size(ptr);
  +}
  +
  // ensure we don't concurrently allocate/mess with internal heap data
  // structures while forking. This is not normally invoked when
  // libmesh is dynamically linked or LD_PRELOADed into a binary.
  