bug#57677: GIMP retains reference to GCC

[Ludovic Courtès]

>From ca. commit 2183db8d2ab773f41e4320367645880b06959bfc:

--8<---------------cut here---------------start------------->8---
$ guix size gimp | head -4
store item                                                       total    self
/gnu/store/wdm2s2si8fqsrcd5xpc29ivmpkf20s8d-mesa-21.3.8            411.6   
169.6  14.1%
/gnu/store/6pdzpmxg5afzss6dlivq8z84sfa31x22-llvm-11.0.0            221.5   
149.5  12.4%
/gnu/store/069aq2v993kpc41yabp5b6vm4wb9jkhg-gcc-10.3.0             217.7   
145.8  12.1%
$ guix graph --path -t references 
/gnu/store/m4s1ghyqp05irx8acz2mqa68lyclcsrz-gimp-2.10.32 
/gnu/store/069aq2v993kpc41yabp5b6vm4wb9jkhg-gcc-10.3.0  
/gnu/store/m4s1ghyqp05irx8acz2mqa68lyclcsrz-gimp-2.10.32
/gnu/store/069aq2v993kpc41yabp5b6vm4wb9jkhg-gcc-10.3.0
$ grep -r 069aq2v993kpc41yabp5b6vm4wb9jkhg 
/gnu/store/m4s1ghyqp05irx8acz2mqa68lyclcsrz-gimp-2.10.32
grep: 
/gnu/store/m4s1ghyqp05irx8acz2mqa68lyclcsrz-gimp-2.10.32/libexec/gimp-debug-tool-2.0:
 binary file matches
grep: 
/gnu/store/m4s1ghyqp05irx8acz2mqa68lyclcsrz-gimp-2.10.32/bin/gimp-console-2.10: 
binary file matches
grep: /gnu/store/m4s1ghyqp05irx8acz2mqa68lyclcsrz-gimp-2.10.32/bin/gimp-2.10: 
binary file matches
$ strings 
/gnu/store/m4s1ghyqp05irx8acz2mqa68lyclcsrz-gimp-2.10.32/bin/gimp-console-2.10 
| grep -C3  069aq2v993kpc41yabp5b6vm4wb9jkhg
GNU Image Manipulation Program
        Using built-in specs.
        COLLECT_GCC=gcc
        
COLLECT_LTO_WRAPPER=/gnu/store/069aq2v993kpc41yabp5b6vm4wb9jkhg-gcc-10.3.0/libexec/gcc/x86_64-unknown-linux-gnu/10.3.0/lto-wrapper
        Target: x86_64-unknown-linux-gnu
        Configured with: 
        Thread model: posix
--8<---------------cut here---------------end--------------->8---

So the root cause is that GIMP’s build process captures the output of
‘gcc -v’, which leads to this unintended retention.

Ludo’.