performing updates from gcc cvs and building

[Mathieu Lacage]

hi,

I did a gcc check from cvs HEAD, then, a few days later, I updated with
contrib/gcc_update, rm -rf objdir/*, configure again with c and c++
only, make, touch gcc/tree-optimize.c, make and I get the following
error:
gcc -c   -g -O2 -DIN_GCC   -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -pedantic -Wno-long-long -Wno-variadic-macros -
Wold-style-definition -fno-common   -DHAVE_CONFIG_H    -I. -I. -
I../../gcc -I../../gcc/. -I../../gcc/../include -
I../../gcc/../libcpp/include  ../../gcc/tree-optimize.c -o tree-
optimize.o
cc1: error: unrecognized command line option "-Wno-variadic-macros"

Would someone be kind enough to tell me what I do wrong ? I failed to
find any kind of information on how to repeatedly build gcc in the same
objdir directory without doing a complete rm -rf objdir/* between each
build which I find annoying...

regards,
Mathieu
--