Re: Installing a wrapper guile script in <out>/bin

[elaexuotee@wilsonb.com]

Ludovic Courtès <ludovic.courtes@inria.fr> wrote:
> I wrote about this topic in the past:
> 
>   https://hpc.guix.info/blog/2018/01/pre-built-binaries-vs-performance/

Very nice overview! Thanks for sharing (and writing!) that article. Definitely
feeling the urge to jump down this rabbit hole and patch upstream now. Hehe.

> I you’re the upstream author, I recommend using one of the techniques
> given above to provide so-called “fat binaries” that contain several
> implementations of the performance-sensitive functions; the loader
> will pick the right implementation when the program starts.
> 
> If you’re downstream… it depends on the specifics.  The loader is also
> able to pick a .so from the right lib/ sub-directory depending on the
> micro-architecture.  You can try:

I'm downstream, unfortunately. However, the final executable actually provides
a flag to explicitly specify a path to the lib, so that's not really a hurdle
in this case.

Given the small size of the build products, I feel like it would be nice to
fake a fat binary at the filesystem level. Mind if we just entertain this idea
for a second?

Say I have a script that reads /proc/cpuinfo and runs my executable with the
correct flags to load the library with the best CPU features possible. How can
I embed such a script in the package definition (as a gexp?) and install it
under <out>/bin/?