Warnings building current master

Building current master I see some warnings that seem new to me (the
only one I remember is the one in Hasher.cc):

[ 1%] Building CXX object
aux/binpac/src/CMakeFiles/binpac.dir/pac_scan.cc.o
/home/jgras/devel/bro/build/aux/binpac/src/pac_scan.cc: In function
‘yy_buffer_state* yy_scan_bytes(const char*, yy_size_t)’:
/home/jgras/devel/bro/build/aux/binpac/src/pac_scan.cc:2290:19: warning:
comparison between signed and unsigned integer expressions [-Wsign-compare]
  for ( i = 0; i < _yybytes_len; ++i )
                   ^

What compiler is giving these errors? I haven't been seeing these.

  .Seth

What compiler is giving these errors? I haven't been seeing these.

I was using gcc 4.8.5 on CentOS 7.