Re: [pocl-devel] intermittent clang ComputeLineNumbers SegFault

[Andreas K. <li...@in...>]

Noah,

Noah Reddell <noa...@gm...> writes:
>> Having it on /tmp on many systems makes the cache non-persistent, which
>> kind of defeats the purpose of having a cache in the first place... perhaps
>> there is a more suitable place, but i'm not aware of it.
>>
> There's a complex set of factors to balance for sure.  Since the default
> behavior is to remove build products, I don't think the default
> POCL_CACHE_DIR needs to be persistent storage. $HOME is generally going to
> be slower and farther away than $TMPDIR.
>     Most importantly the behavior is already customizable through
> POCL_CACHE_DIR variable. I have a work-around.  A general user wouldn't
> know to adjust the variable upon encountering this SEGFAULT unless
> discovering record of this discussion.

~/.cache (or, really, whatever $XDG_CACHE_HOME points to) is the default
location for "user-specific non-essential data files" under the XDG Base
Directory Specification [1]. While that's a desktop-focused spec, it
establishes a convention that is independent of the desktop use case per
se. In particular, all parts of the spec are applicable (in a technical
sense) even in a command line context.

Arguably, the machine you are using should be configured to put
$XDG_CACHE_HOME someplace sensible (ideally, on a per-compute-node
FS). IMO, this would be a much preferable outcome compared to inventing
yet another convention or reverting to someplace in $TMPDIR, which is
insecure in a multi-user workstation/desktop setting.

[1] https://specifications.freedesktop.org/basedir-spec/latest/

Andreas