bug#63728: GHC cannot find lrt

[Antero Mejr]

Mekeor Melire <mekeor@posteo.de> writes:

> 2023-05-25 22:25 bug-guix@gnu.org:
>
>> Attempting to build a trivial Haskell program using ghc fails, as the linker
>> cannot find the rt library:
>
> Does installing gcc-toolchain:static help as a work-around?

I merged this bug with #63258.

The gcc-toolchain:static workaround fixes the rt problem, but now the
binaries aren't linked to libgmp and libffi, even though gmp and libffi
packages are installed in the profile:

--8<---------------cut here---------------start------------->8---
~$ ghc -O2 test.hs
~$ ldd ./test
  linux-vdso.so.1 (0x00007ffe0956f000)
  libgmp.so.10 => not found
  libc.so.6 => 
/gnu/store/gsjczqir1wbz8p770zndrpw4rnppmxi3-glibc-2.35/lib/libc.so.6 
(0x00007fbe27e3f000)
  libm.so.6 => 
/gnu/store/gsjczqir1wbz8p770zndrpw4rnppmxi3-glibc-2.35/lib/libm.so.6 
(0x00007fbe27d62000)
  libffi.so.8 => not found
  libgcc_s.so.1 => 
/gnu/store/qcg59v4yg239jj1k0xvqqqkqv6l8q6ll-gcc-12.2.0-lib/lib/libgcc_s.so.1 
(0x00007fbe27d41000)
  
/gnu/store/gsjczqir1wbz8p770zndrpw4rnppmxi3-glibc-2.35/lib/ld-linux-x86-64.so.2 
=> 
/gnu/store/ip9mj1pwymxi1yq32zbhwp3n3bycy6yi-glibc-2.35/lib/ld-linux-x86-64.so.2 
(0x00007fbe2803d000)
--8<---------------cut here---------------end--------------->8---

Maybe there should be a ghc-toolchain package that has libgmp and
libffi as inputs, and makes sure GHC links them correctly?