How to rebuild world after changing one .c file.


Staff member
Add -DNO_CLEAN so it only rebuilds what is required to be rebuilt, instead of building everything from scratch.


-DNO_CLEAN can sometimes lead to strange problems (rare, but possible).

In most cases, using meta-mode solves this issue nicely:
  • make sure you have filemon(4) (filemon.ko) loaded
  • Add WITH_META_MODE=yes to /etc/src-env.conf
Edit: you need one complete build with meta-mode enabled before you can benefit from it ;)


Yeah, don't use it when has been changed. It'll lead to some really weird version errors.
I'd assume this is not the only thing that can go wrong with -DNO_CLEAN. Admittedly, it will work fine as a one-time solution when you really just did a trivial change :)

Still, meta-mode is designed to address the problem once and for all without any risks. There are some complaints that even with meta-mode, there are situations with unnecessary rebuilds, but it does help a lot (and definitely works in this "trivial change" situation).
you can build only the program / lib that the file belongs to
for most stuff cd /usr/src/bin/echo;make all install