When building the DRI drivers from git, libglsl and libdricore seem to always be built and used as shared libraries. This makes it much less convenient to test drivers with LIBGL_DRIVERS_PATH=.../mesa/lib -- it'll look for libglsl.so and libdricore.so in the normal system library paths and fail to load. 8.0 doesn't have this problem.
We killed off libglsl.so and libdricore.so a few releases ago, as you already know.
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