CFLAGS='-mtune=generic -Os -pipe -flto'
CXXFLAGS='-mtune=generic -Os -pipe -flto'
LDFLAGS='-Wl,-O1'

compiletc
bzip2-dev
curl-dev
coreutils

./configure --prefix=/usr/local

make -j16
real    0m 46.92s
user    9m 53.85s
sys     0m 12.08s