Testsuite breakages on Cygwin

[Daniel Santos]

On 03/10/2017 11:23 AM, Joseph Myers wrote:
> On Fri, 10 Mar 2017, Daniel Santos wrote:
>
>> 3. Wouldn't it be better to move this logic up into DejaGnu and restrict gcc
>> to using a black-box interface for modifying the environment?
> GCC is meant to work with a wide range of different DejaGnu versions.
> There would be a long gap between adding board-file interfaces for
> controlling library paths - because that's the right level, interfaces
> that a board file can define alongside open, close, load, exec, spawn,
> etc. - and being able to assume they are available.  Of course you might
> try to arrange things so that existing board files not defining such
> interfaces continue to work (most custom board files are likely to be for
> bare metal where shared libraries don't exist) and so that GCC continues
> to work with versions of DejaGnu without such interfaces.

Thanks for the explanation.  So maybe the best approach is to migrate 
this upstream, but also corral this functionality into a single place in 
gcc and use gcc's implementation when the DejaGnu doesn't have the new 
interface.

> Finding shared libraries is generally simpler with installed testing, in
> that it becomes the responsibility of the board file, site.exp and the
> rest of the user-provided test environment to arrange for shared libraries
> to be in locations where they are found automatically.

In my case I have 8 full tests that need to be run, so this would mean 
installing and uninstalling 8 times.  I have a crude patch set that 
seems to be doing the job for now.  I guess I'm trying to work out a 
reasonable and clean solution for a patch set that I would actually 
submit. :)  It would be a lot easier if cygwin had an ldconfig 
implementation, but almost all shared libs just sit in /bin.

Daniel