I think the following is a better suggestion:
% CC='gcc -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64' ./configure
CC is propagated to the Makefile so that just "make" is necessary, but OPT and CFLAGS is not. (Although, I seem to vaguely remember that OPT /used/ to propagate -- I must be mis-remebering.)
What version of configure are you using? On my system, with configure 1.207.2.7, doing CFLAGS='-D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64' OPT="-g -O2 $CFLAGS" ./configure will result in a line OPT= -g -O2 -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 in the Makefile. This, in turn, will result in a compilation line gcc -c -g -O2 -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I. -I./Include -DHAVE_CONFIG_H -o Objects/fileobject.o Objects/fileobject.c Something else is going on on your system. Did you remove config.cache before running configure? Regards, Martin