Example: x86_64-pc-linux-gnu-gcc -DLOCALEDIR=\"/usr/share/locale\" -DHAVE_CONFIG_H -I. -I.. -I. -I.. -I../intl -I/usr/include/freetype2 -I/usr/include/freetype2 -O2 -march=native -O2 -g0 -c -o xvt.o `test -f '../xvt/xvt.c' || echo './'`../xvt/xvt.c amd64box ~ # portageq envvar CFLAGS -march=native -O2 -g0 So, If I delete my -O2 it will be built always with -O2 added by the buildsystem.
you can and should set "-O0" if you don't want opzimization otherwise we would have to fix a LOT of packages for no real gain
fixed