Installing this private library into the default library
search path avoids needing to rely on -Wl,-rpath,
which is inconsistently implemented as either DT_RUNPATH
or DT_RPATH on different distributions; in particular,
on distributions that implement it as DT_RPATH,
it interferes with use of LD_LIBRARY_PATH and has semantics
that are difficult to reason about, and is incompatible with
Steam's container runtime (which has the known limitation that
it only implements DT_RUNPATH and not DT_RPATH).
To avoid third-party developers being tempted to link to the
unstable libgallium, give it a name that varies with each Mesa release,
so that there is no obvious way for third-party software to link to it.
This is similar to the way the proprietary Nvidia driver sets up its similar
implementation-detail libraries such as libnvidia-glcore.so.535.183.01.
Fixes: 50fc7cc2 ("glx: directly link to gallium")
Acked-by: Daniel Stone <daniels@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30328>
(cherry picked from commit 9b7bb6cc9f)