The traditional
makefile target for cleaning up various files, particularly
object files from the build. Normally you want to keep them around; the whole
point of
make is that it only
rebuilds the object files that
need to be rebuilt. But sometimes you want to get rid of all the by-products, so you add a
clean target to your makefile. A simple
clean target could look something like this:
clean:
/bin/rm -f $(OBJS)
# The previous line MUST start with a TAB!
Here it's assumed
variable(OBJS) holds the names of all the object files in the
project.
Two common uses for make clean:
- A build is just "make clean; make all".
- Since make only looks at modification times of files, if you want to change the compilation flags you have to force all targets to be rebuilt; "make clean; make CFLAGS=-g" is a good way to do this.