Extreme CFLAGS problems...

[racoontje]

Japanese Honda rice munchers?

[valkyrite]

Do LDFLAGS help and how??
Should I use LDFLAGS="-s" in my make.conf. Does it give any significant performance gain.

I am using the following CFLAGS and my system rocks
CFLAGS="-O2 -march=pentium4 -pipe -fomit-frame-pointer"
I guess all other CFLAGS bloat the system rather than make it actually fast.

TIA

[ciaranm]

[Xaignar]

Why not have a list of officially supported C(XX)FLAGS, and then just make portage post a big honking "WTF are you doing?" warning if a non-supported flag are used when emerge/etc is evoked?

[ciaranm]

[Xaignar]

[ciaranm]

[Xaignar]

[BrightSide]

How about including "filter-cflags" in Portage's feature list instead of forcing filtering on users and leaving it turned on by default? That way, everyone would still be able to enjoy a stable system but it's possible to turn it off for those who want to play with flags other than the "known to work" ones.

Gentoo has always been about choice and most of that choice in my view comes from not only what is being built (through the use flags) but also how it is being build (through the cflags) so if you want to turn of the safe compile-flags feature and break your system. Well, that should be your choice.

[ciaranm]

[TrueDFX]

Do you disagree that Gentoo is about choice, or do you feel that it's simply not relevant?

[thechris]

i had a similar idea. except i delegated it to what i called the "gentoo extreme project". basically people are rightfully afraid to use certain cflags. My idea involved a "package.cflags" feature in portage, something which people either agree with or think is not needed. please note that such a featuer may be very useful for amd64, where 32 bit binaries are STRONGLY reccomended to be compiled manually with the -m32 option.

from here you just have to have a organization of gentooers that want to test programs with cflags to see if: 1. they compile; 2. pass maketest; 3. work when used. a package.cflags might be made from a database made by these users -- basically a community effort.

I have other non-performance reasons for a package.cflags. a major issue with it however is that portage doesn't control gcc, thus when gcc deprecates -mcpu, the package.cflags will need to be changed.

[ciaranm]

[TrueDFX]

No argument there, then, but BrightSide's suggestion makes sense for other reasons too. One possible example might be to continue using a system built with -mregparm (I won't get into a discussion of whether it's a good idea to do that).

[mcspiff]

View ciaranm packages (that he maintains). This are some of the most rock solid packages on gentoo, and the most used. Thus his feelings on "Experimental" and the benefits of having gentoo be bleeding edge (with support) is somewhat different than the rest of us. Which is fine. I honestly doubt you'll change his mind

[Xithix]

Why does gcc even include flags like -malign-double if they are so obviously dangerous to the point that no one in their right mind would ever use them?

Experimental flags I can understand. Leaving something that never should be used under any circumstance in gcc is spreading the problem.

I understand that Gentoo devs are not gcc devs ... but still, it seems like the gcc devs, by including the flags (as warnings are ignored) are as much to blame as the "ricers" abusing them.

[ciaranm]

[rhill]

[fca]

OK, I feel like chiming in on this and play the devil's advocate a bit:
Sometimes these "insane" flags actually do the right thing and make a task that needs speed a bit faster.

Let met focus on -ffast-math, the bane of all Gentoo developers:
What does it do?

[Athas]

[Joelio]

This is my set of flags for a super 1337 system..

[Lokheed]

[psyqil]

[Xaignar]

Humm, he forgot "-ffuzzy-dice", that makes all the difference.

[thechris]

never forget -fsticker=type-r,azn,nos,prenelli,honda. it add 50 bogomips.
_________________
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