need help on CFLAGS in /etc/make.conf please

Paul Seniura pdseniura at
Thu Feb 12 19:56:09 PST 2004

Hi Kris,

> On Thu, Feb 12, 2004 at 06:17:03PM -0600, Paul Seniura wrote:
> > 
> > Hi y'all,
> > 
> > I'm trying to find a way to do a CFLAGS+='-O' if and only if such a
> > parm was not already provided before 'make' actually runs.
> > 
> > I had this coded with the single = sign, i.e. without ?= or +=, but
> > the process still acts as if += was coded anyway, thus tacking on
> > my -O *after* the port's own CFLAGS.
> > 
> > GCC33 docs say the _last_ -O# is the one that will be used.
> > 
> > I've seen other discussion on using -O2 but the point seems to be the
> > ports that set -O2 explicitly are likely to work correctly.

On Thu 12 Feb 2004 17:13:25 -0800, Kris Kennaway replied:
> That's not a good assumption; many ports simply add -O2 (or -O3, or
> -O999) because the authors "want their code to run fast".  The set of
> ports for which the authors have run full regression suites for all
> supported versions of gcc and all supported OS and architecture
> combinations is probably the null set.

Thank you for responding, but I'm *really* not wanting this to
become another discussion on "how high my Oh-levels should be". ;)

My question for this discussion is specifically how to prevent
overriding a port's own setting for that parm, and to provide a
default setting -O[1] when the port does not set it at all?

(I'll save my l-o-n-g-e-r reply for later... believe me I have reasons ;)

> Kris

  --  thx, Paul Seniura (in OkC)

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