| 1 |
On Tue, 2003-10-21 at 13:39, Stroller wrote: |
| 2 |
> On Oct 21, 2003, at 2:15 pm, Chris Gianelloni wrote: |
| 3 |
> > |
| 4 |
> > I would definitely *not* use a USE flags at all, since a USE flag is |
| 5 |
> > for |
| 6 |
> > adding or removing optional features from a package. If anything were |
| 7 |
> > to be used, it would be a FEATURE flag. |
| 8 |
> |
| 9 |
> I am aware of the -devs attitude towards USE-flag bloat, and my |
| 10 |
> original posting "you can never have too many USE flags" was intended |
| 11 |
> as a joke (obviously a very poor one). However, from a user perspective |
| 12 |
> USE flags are quite desirable - they keep all options in one place, I |
| 13 |
> can `emerge -vp someapp` & easily use `ufed` to determine what each |
| 14 |
> flag means & change it as required. |
| 15 |
|
| 16 |
However, a USE flag has a specific function and should stay that way to |
| 17 |
keep confusion down. There are already a few cases where USE flags are |
| 18 |
used to do things they shouldn't be. |
| 19 |
|
| 20 |
> You say that "a USE flag is for adding or removing optional features |
| 21 |
> from a package", however I am not really clear what this means. My |
| 22 |
> recent experimentation, for instance, with the prelinking & the "pic" |
| 23 |
> USE flag seems to indicate that "-fPIC" will be added to the user's |
| 24 |
> CFLAGS. But only, I think, if the package supports prelinking..? |
| 25 |
|
| 26 |
The -fPIC is actually used to enable PIC support in applications. For |
| 27 |
example, if you were to have -fPIC in your CFLAGS, there are some |
| 28 |
packages that will NOT compile. The pic USE flag is for enabling -fPIC |
| 29 |
in a way which is suitable to the package. It isn't just tacking |
| 30 |
"-fPIC" onto your CFLAGS and that's it. In many cases it requires |
| 31 |
patches to the source, which aren't needed when not compiling with |
| 32 |
-fPIC. |
| 33 |
|
| 34 |
> Having USE flags change CFLAGS seems to me to be non-intuitive, and I |
| 35 |
> don't really see how a "patches" USE flag is any different from the |
| 36 |
> existing "mmx", "oss", or (to be honest) any other USE flags. |
| 37 |
|
| 38 |
Let's take... a fictional game I would like to call GentooRulez. |
| 39 |
GentooRulez can use mmx, but only if it is added on the ./configure line |
| 40 |
with a --enable-mmx. Otherwise, it builds without. This is the prime |
| 41 |
example of when to use the mmx USE flag. |
| 42 |
|
| 43 |
Now, a new version of GentooRulez comes out and you want to merge it |
| 44 |
using patches. You are wanting to tell PORTAGE itself to use patches. |
| 45 |
It makes no changes to the actual configuration/build. FEATURES control |
| 46 |
portage itself. USE flags control the package compilation/install |
| 47 |
options. |
| 48 |
|
| 49 |
> Could someone be so kind as to explain when a USE flag should & should |
| 50 |
> not be used, and what is the difference between USE flags & FEATUREs..? |
| 51 |
> |
| 52 |
> Many thanks, |
| 53 |
> |
| 54 |
> Stroller. |
| 55 |
-- |
| 56 |
Chris Gianelloni |
| 57 |
Developer, Gentoo Linux |
| 58 |
Games Team |
| 59 |
|
| 60 |
Is your power animal a pengiun? |
Archives