On 01/13/2014 07:06 PM, Fam Zheng wrote: > On Mon, 01/13 14:15, Richard Henderson wrote: >> On 01/13/2014 08:59 AM, Paolo Bonzini wrote: >>> +echo "CONFIG_STAMP=`date +%s`_$$_$RANDOM" >> $config_host_mak >> >> I really really don't like random numbers that make for non-repeatable >> builds. >> It's a quality-assurance nightmare. > > Can you elaborate this, please?
Build systems like we use at Red Hat want to be able to produce bit-for-bit identical binaries when given the exact same input. Using random numbers during the build process prevents that. >> and perhaps a file containing that hash created by scripts/make-release. > > What if the source code is not in a git tree, for example a tarball? You just quoted my answer to that. Alternately, take a page from gcc and produce a number from a hash of the relevant object file(s). r~
