gcc-6.3: backport fix of check for empty string in ubsan.c
Building gcc-cross-initial with GCC7 on the host fails due to the
comparison of a pointer to an integer in ubsan_use_new_style_p, which
is forbidden by ISO C++:
ubsan.c:1474:23: error: ISO C++ forbids comparison between pointer and
integer [-fpermissive]
|| xloc.file == '\0' || xloc.file[0] == '\xff'
Backport the fix from upstream GCC to enable the build with GCC 7
Signed-off-by: Joshua Lock <joshua.g.lock@intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
