groff 1.18 build failure

[Paul Jarc]

Building groff 1.18 with gcc 3.1 and glibc 2.2.5 produces this error:
g++ -I. -I/home/prj/src/sptools/groff-1.18/src/roff/troff 
-I/home/prj/src/sptools/groff-1.18/src/include 
-I/home/prj/src/sptools/groff-1.18/src/include -DHAVE_CONFIG_H -g -O2 -I/nil -c 
input.cc
input.cc:56: declaration of `int isatty(int)' throws different exceptions
/package/host/localhost/groff-1.18/conf/libc/include/unistd.h:668: than 
   previous declaration `int isatty(int) throw ()'
make[2]: *** [input.o] Error 1
make[2]: Leaving directory 
`/fs/home/mount/home/prj/src/sptools/groff-1.18/src/roff/troff'
make[1]: *** [src/roff/troff] Error 2
make[1]: Leaving directory `/fs/home/mount/home/prj/src/sptools/groff-1.18'
make: *** [all] Error 2


paul