RISC-V glibc port, v5

[Palmer Dabbelt]

On Fri, 26 Jan 2018 04:08:59 PST (-0800), joseph@codesourcery.com wrote:
> On Thu, 25 Jan 2018, Palmer Dabbelt wrote:
>
>> > And dl-cache.h is missing a definition of add_system_dir.
>>
>> When I looked through that I didn't think we needed one because libraries were
>> always in paths defined by the arch/abi pair.  Our libraries live in
>>  */lib64/lp64d
>>  */lib64/lp64
>>  */lib
>>
>> with only ld.so living in */lib (as ld-linux-*.so).  Looking through the
>> existing codebases it appears that I'm supposed to be adding all the
>> directories in which we could find libraries for any library path argument
>> add_system_dir is given.
>
> Yes.  My reasoning for that would be: generic autoconf-configured (etc.)
> software may only know about using the lib directory, so you want the lib
> directory to be searched regardless of the ABI - but it's also useful to
> be able to e.g. list /usr/local/lib in /etc/ld.so.conf for all
> architectures and have that automatically imply /usr/local/lib64/lp64d
> etc. so that libraries can be found that come from software that does use
> the ABI-specific directories.

OK, that makes sense.  I'm going to add that to our port, just in case anyone 
else ends up coming across this and wondering what it's there for.