PVS-Studio warning V627 for samba

#define HBIN_HDR_SIZE    4

char header[HBIN_HDR_SIZE];

static REGF_HBIN* regf_hbin_allocate(REGF_FILE *file,
                                     uint32 block_size)
{
  REGF_HBIN *hbin;
  ....
  memcpy( hbin->header, "hbin", sizeof(HBIN_HDR_SIZE) );
  ....
}

It works. Good luck: sizeof(4) == 4.

This suspicious code was found in samba project by PVS-Studio static code analyzer.
Warning message is:
V627 Consider inspecting the expression. The argument of sizeof() is the macro which expands to a number. regfio.c 1470

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/