On Thu, 19 Oct 2006 20:43:28 +0000 (UTC)
"Duncan" <1i5t5.duncan@cox.net> wrote:

> Simon Stelling <blubb@gentoo.org> posted 45379CDC.1010504@gentoo.org,
> excerpted below, on  Thu, 19 Oct 2006 17:42:20 +0200:
> 
> > If you want to add instead of replace, CFLAGS="${CFLAGS} -fadded"
> > will do the job. Removing is done with CFLAGS=" ${CFLAGS}" ;
> > CFLAGS=${CFLAGS//-fremoved}

FWIW I think Simon meant:

CFLAGS=" ${CFLAGS}" ; CFLAGS=${CFLAGS// -fremoved}

assuming that adding the space was done to catch flags that match part
of longer flags.

> > So you can do effectively anything, given you know the bash
> > tricks ;)
> 
> Hey, thanks!  The add was a no-brainer here, but I hadn't thought
> about the remove trick yet.  Very nice! =8^)

Watch also for flags that start with the same string; for example:

  CFLAGS=${CFLAGS// -finline-functions}

would end up with "-called-once" in CFLAGS, if
"-finline-functions-called-once" was set.

Another easy one is doing:

  CFLAGS=${CFLAGS// -g}

when CFLAGS has "-ggdb2" or similar set...

-- 
Kevin F. Quinn