Date: Tue, 12 Feb 2013 19:39:33 -0800 From: Steve Kargl <sgk@troutmask.apl.washington.edu> To: bf1783@gmail.com Cc: freebsd-current@freebsd.org, Anton Shterenlikht <mexas@bristol.ac.uk> Subject: Re: 7+ days of dogfood Message-ID: <20130213033933.GA89757@troutmask.apl.washington.edu> In-Reply-To: <CAGFTUwOvZ3CcZzYaxgDr6yb6AoDAPvqvs3vqh0_EjS6jFx-kbA@mail.gmail.com> References: <CAGFTUwN3Rrq-S_7uwZ%2B5MkbG1O7k59JK%2Bv-2qFoQ%2BofkMjyUEg@mail.gmail.com> <20130213014734.GA89321@troutmask.apl.washington.edu> <CAGFTUwOvZ3CcZzYaxgDr6yb6AoDAPvqvs3vqh0_EjS6jFx-kbA@mail.gmail.com>
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On Wed, Feb 13, 2013 at 02:15:08AM +0000, b.f. wrote: > On 2/13/13, Steve Kargl <sgk@troutmask.apl.washington.edu> wrote: > > On Wed, Feb 13, 2013 at 12:18:29AM +0000, b.f. wrote: > >> ># cat /etc/make.conf|grep FFLAGS > >> >FFLAGS = -O2 -pipe -march=native -mtune=native > >> > >> Please do _not_ assign flags unconditionally in make.conf. > > > > FFLAGS is for compiling Fortran. I'm one of the people who > > has spent years working/patching gfortran. I think I might > > have a better understanding of what options to use with > > gfortran than most people. > > > > I know you have, but you are giving advice that is liable to be abused > by those who are less experienced. The flags you are adding are not > the problem -- it's the way that you are adding them -- specifically, > the assignment in the first line of your snippet, if it's applied > unconditionally. You should either be appending all of them, or > assigning them conditionally, so that they are sure to be assigned > only once, or -- preferably -- using another makefile that can't be > re-read multiple times during a build (ports/Mk/bsd.port.mk > automatically includes several makefiles that can be used for this > purpose, if you are building a port). You have been lucky not to trip > over this: every couple of months for the last several years I have > had to debug errors reported by users that arise from this problem. It > is more common with CFLAGS and CXXFLAGS but it can happen with FFLAGS, > too. Try 'find /usr/ports -name Makefile -maxdepth 3 | xargs grep FFLAGS' Then go read about the options chosen by the various port maintainers. I specifically set FFLAGS to avoid the questionable options set in the ports. If -malign-double appears in a port, it should probably be marked as broken. If a port uses -fdefault-real-8, it should probably be marked as broken. If a port uses -ffast-math, it may have issues that are extremely difficult to debug. -- steve
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