On Tue, 2006-05-30 at 08:04 +0200, Bo Ørsted Andresen wrote: > Tuesday 30 May 2006 07:41 skrev Graham Murray: > > > Besides, by looking at the terminal while merging packages, you will > > > soon notice, that lot's of packages add their very own CFLAGS to your > > > default ones. For example mplayer or xine-lib was compiled with '-O3' on > > > my system, allthough i have '-O2' in my CFLAGS. (As far as i know, "gcc > > > -O3 -O2" == "gcc -O3"). > > > > Where packages do this, should they not filter out the appropriate > > flags from the user's CFLAGS and substitute their flags rather than > > having both flags on the command line? > > Not in this particular case. xine-lib is a good example. src_compile() > contains the following in the ebuild (and more): > > if [[ $(tc-arch) == "x86" ]]; then > filter-flags -fforce-addr > filter-flags -momit-leaf-frame-pointer > is-flag -O? || append-flags -O2 > fi > > On an x86 architecture it filters out -fforce-addr > and -momit-leaf-frame-pointer. If the CFLAGS contain any optimizations it > just appends -O2 yielding that -O2 will be used as stated by Christian > Limberg. In 'man gcc' you find the following statement: > > "If you use multiple -O options, with or without level numbers, the last such > option is the one that is effective." > > So this is completely legal. > > And I very much doubt that there are any ebuilds in the portage tree that > enforces -O3 or higher... > Well, you are right: However, what i said still applies: Lot's of packages add their very own CFLAGS (-fomit-frame-pointer, -ffunction-sections are two examples for xine-lib).
Matthias -- gentoo-user@gentoo.org mailing list
