gperftools: google-perftools-2.5 compile error on gentoo for mips loongson2f CPU

The error message : In file included from /var/tmp/portage/dev-util/google-perftools-2.5/work/gperftools-2.5/src/malloc_hook.cc:678:0: /var/tmp/portage/dev-util/google-perftools-2.5/work/gperftools-2.5/src/malloc_hook_mmap_linux.h: In function ‘void* do_mmap64(void*, size_t, int, int, int, __off64_t)’ :

/var/tmp/portage/dev-util/google-perftools-2.5/work/gperftools-2.5/src/malloc_hook_mmap_linux.h:86:30: error: 'SYS_mmap2' was not declared in this scope
 result = (void *)syscall(SYS_mmap2,
                          ^

Makefile:4734: recipe for target ‘src/libtcmalloc_minimal_internal_la-malloc_hook.lo’ failed make: *** [src/libtcmalloc_minimal_internal_la-malloc_hook.lo] Error 1

• ERROR: dev-util/google-perftools-2.5::gentoo failed (compile phase):
• emake failed
• If you need support, post the output of emerge --info '=dev-util/google-perftools-2.5::gentoo',
• the complete build log and the output of emerge -pqv '=dev-util/google-perftools-2.5::gentoo'.
• The complete build log is located at ‘/var/tmp/portage/dev-util/google-perftools-2.5/temp/build.log’.
• The ebuild environment file is located at ‘/var/tmp/portage/dev-util/google-perftools-2.5/temp/environment’.
• Working directory: ‘/var/tmp/portage/dev-util/google-perftools-2.5/work/gperftools-2.5-abi_mips_n32.n32’
• S: ‘/var/tmp/portage/dev-util/google-perftools-2.5/work/gperftools-2.5’