Compilers and Options
=====================
Some systems require unusual options for compilation or linking that
the `configure' script does not know about. Run `./configure --help'
for details on some of the pertinent environment variables.
You can give `configure' initial values for variables by setting
them in the environment. You can do that on the command line like this:
./configure CC=c89 CFLAGS=-O2 LIBS=-lposix
Note:Defining Variables, for more details.