[Fedora-packaging] Draft Changes to static libraries

[Ralf Corsepius]

On Mon, 2007-05-21 at 20:47 -0700, Toshio Kuratomi wrote:
> I've written a draft of changes to the static library guidelines::
>   http://fedoraproject.org/wiki/PackagingDrafts/StaticLibraryChanges
> 
> There are three pieces which can be voted on separately or together
> depending on how controversial they are:
>  1) Separate static library inclusion from static library linkage and
> make static library inclusion less strict.
>  2) Change how to package static libraries when the package does not
> include dynamic libraries (per Ralf's note to the list)
>  3) Incorporate mschwendt's note about *.la files directly into the
> guidelines instead of as a footnote.
> 
> Comments welcome.
+1 +1 +1

One comment interspersed below, also I'd like so see another addition:

"Development libraries" (libraries not being used at runtime) must not
be packaged in /%{_lib}. 

If a package needs "runtime libs in /%{_lib} (Normally lib*.so.* being
used by applications which shall be run at times when /usr might not be
available, typically apps being used at bootup), the corresponding
development libraries (Normally: lib*.so and *.a) should be packaged
into %{_libdir}

> == Exclusion of Static Libraries ==
> Packages including libraries should exclude static libs as far as
> possible (eg by configuring with ''--disable-static'').  Static
> libraries should only be included in exceptional circumstances.
> Applications linking against libraries should as far as possible link
> against shared libraries not static versions.
> 
> Libtool archives, ''foo.la'' files, should not be included. Packages
> using libtool will install these by default even if you configure with
> ''--disable-static'', so they may need to be removed before packaging.
> Due to bugs in older versions of libtool or bugs in programs  that use
> it, there are times when it is not always possible to remove *.la files
> without modifying the program.  In most cases it is fairly easy to work
> with upstream to fix these issues.

If a Fedora release had been shipped with lib*.la's they must not be
removed during this Fedora release's life-time.

> === Packaging Static Libraries ===
>  * In general, packagers are strongly encouraged not to ship static libs
> unless a compelling reason exists.
> 
>  * We want to be able to track which packages are using static libraries
> (so we can find which packages need to be rebuilt if a security flaw in
> a static library is fixed, for instance.)
>   * When a package provides both dynamic and static libraries the static
> libraries must be placed in a ''*-static'' subpackage.  Separating the
> static libs from the other development files in ''*-devel'' allow us to
> track this usage by checking which packages Build''''''Require the
> ''*-static'' package.
>   * When a package only provides static libraries you can place all the
> files in the ''*-devel'' subpackage.  When doing this you also have to
> have a virtual Provide for the static package:
>   {{{
>   %package devel
>   Provides: foo-static = %{version}-%{release}
>   }}}
>   This way other packages which will link against a dynamic library when
> your package starts providing one can {{{BuildRequire: foo-devel}}} and
> packages which explicitly need to link against the static version can
> {{{BuildRequire: foo-static}}}
> 
> === Staticly Linking Executables ===
>  * Static linkage is a special exception and should be decided on a
> case-by-case basis.  The packager must provide rationale for linking
> statically, including precedences where available, to FESCO for
> approval.

Ralf