(In reply to Andy Furniss from comment #22)
> It seems like current mesa doesn't build/install properly when patched
> without being totally clean.
> 
> The mesa patch in this bug on an already built tree does provoke -
> 
> make[3]: Entering directory
> '/mnt/sdb1/Src64/Mesa-git/mesa/src/gallium/drivers/radeon'
>   CC       r600_buffer_common.lo
>   CCLD     libradeon.la
> 
> but radeonsi_dri.so is not changed after make install.

How about lib/gallium/radeonsi_dri.so in the build tree? That gets updated
correctly for me. I don't use make install though, and I'm using an out-of-tree
build, so maybe it's related to one of those. Anyway, please file another
report about that.