On Friday 25 January 2008, Ian Jackson wrote:
> Paul Brook writes ("Re: [Qemu-devel] [PATCH] CPPFLAGS+= in
Makefile.target"):
> > In that case you should always provide a definition in config-host.mak.
> > Under some circumstances make may inherit initial values from elsewhere.
>
> What circumstances ? CPPFLAGS+= overrides (discards) values in the
> environment as well as ones from the command line.
$ cat Makefile
FOO += World
all:
@echo "$(FOO)"
$ FOO=Hello make
Hello World
