Re: static libraries

On 12/09/12 08:02, David Tardon wrote:
> Hi,
>
> On Tue, Sep 11, 2012 at 09:24:30AM +0200, Stephan Bergmann wrote:
> > On 09/10/2012 06:55 PM, Matúš Kukan wrote:
> > > I am pondering gbuildizing neon.
> > > It's built by dmake as dynamic library currently.
> > > Could it be used as static library ?
> > [...]
> > > It's used only in ucb/Library_ucpdav1.mk
> >
> > One gotcha with this logic of preferring a static over a dynamic
> > library when only used as a dependency of one other object is that
> > this requires us to keep track whether a library is used only once
> > or multiple times, to revisit the static vs. dynamic decision.
>
> I guess we could issue a warning when a static library is used multiple
> times. Of course, there are static libraries that are created explicitly
> for that purpose, so we would either need a way to avoid these (a
> whitelist of libs that are allowed to be linked with multiple times) or
> limit this to static libraries from external projects (e.g., doing a
> "registration" in gb_StaticLibrary_use_unpacked).

there are also other reasons for linking statically, such as the
horrible design flaw of ELF shared libraries where all exported symbols
are placed into a single namespace by default; to work around that it is
sometimes a good idea to build something as a static library with hidden
visibility.

also, there are bizarre cases like expat where last time i checked we
linked a UTF-16 variant and a UTF-8 variant into different LO libs (if
only somebody would rid us of those awful UTF-16 strings...).

i don't really think putting a check for this into the build system is
merited; but perhaps somebody proves me wrong by reviewing the list of
currently multiply linked static libraries and finding large waste of
space there :)