Something missing in CircleCI cache system preventing musl-cross-make cache layer to be reused

[tlaurion]

Last merged PR commit a23dbde

Pipeline: https://app.circleci.com/pipelines/github/linuxboot/heads/941/workflows/6deb39cc-390c-46c3-a769-17aae171cc69

Error:

From https://circleci.com/api/v1.1/project/github/linuxboot/heads/23266/output/102/0?file=true&allocation-id=680fa468fc702c621eca966d-0-build%2FABCDEFGH

Apr 28 15:57:48 /bin/sh ./libtool  --tag=CC   --mode=link gcc -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow -Wstack-usage=262144 -Wwrite-strings -I../../src_binutils/gas/../zlib -g -O2   -o as-new app.o as.o atof-generic.o compress-debug.o cond.o depend.o dwarf2dbg.o dw2gencfi.o ecoff.o ehopt.o expr.o flonum-copy.o flonum-konst.o flonum-mult.o frags.o hash.o input-file.o input-scrub.o listing.o literal.o macro.o messages.o output-file.o read.o remap.o sb.o stabs.o subsegs.o symbols.o write.o config/tc-i386.o config/obj-elf.o config/atof-ieee.o  ../opcodes/libopcodes.la ../bfd/libbfd.la ../libiberty/libiberty.a   
Apr 28 15:57:48 /root/heads/build/x86/musl-cross-make-fd6be58297ee21fcba89216ccd0d4aca1e3f1c5c/build/local/x86_64-linux-musl/obj_gcc/./gcc/as: line 106: /root/heads/build/x86/musl-cross-make-fd6be58297ee21fcba89216ccd0d4aca1e3f1c5c/build/local/x86_64-linux-musl/obj_binutils/gas/as-new: No such file or directory
Apr 28 15:57:48 installing ../../../src_binutils/ld/po/ja.gmo as /root/heads/crossgcc/x86/share/locale/ja/LC_MESSAGES/ld.mo
Apr 28 15:57:48 make[6]: *** [Makefile:575: gets-chk.lo] Error 1
Apr 28 15:57:48 make[6]: Leaving directory '/root/heads/build/x86/musl-cross-make-fd6be58297ee21fcba89216ccd0d4aca1e3f1c5c/build/local/x86_64-linux-musl/obj_gcc/x86_64-linux-musl/libssp'
Apr 28 15:57:48 make[5]: *** [Makefile:13082: install-target-libssp] Error 2

This is cache layer 3 reusal (only initrd/* script changed, so prep_env step attempts reusal of nix-docker-heads-modules-and-patches-xASxiebP6QSjGACC7Jec1003wreYpIeYSOTin_6fTmM=20250417 as can be seen at https://circleci.com/api/v1.1/project/github/linuxboot/heads/23264/output/107/0?file=true&allocation-id=680fa03d972b793c1736257a-0-build%2FABCDEFGH for step "restoring cache"

Found a cache from build 23245 at nix-docker-heads-modules-and-patches-xASxiebP6QSjGACC7Jec1003wreYpIeYSOTin_6fTmM=20250417
Size: 6.4 GiB
Cached paths:
  * /root/heads/build
  * /root/heads/crossgcc
  * /root/heads/install
  * /root/heads/packages

Downloading cache archive...Download duration for cache file /tmp/cache3630465004: 1m30.010638222s

Unarchiving cache...
Extraction duration for nix-docker-heads-modules-and-patches-{{ checksum "./tmpDir/all_modules_and_patches.sha256sums" }}{{ .Environment.CACHE_VERSION }}: 2m35.319990993s

[tlaurion]

For the moment, will rebuild a23dbdea3fdf40f8070816e645ea73f0dead0df1without cache, with means in practice changing CACHE_VERSION env variable to something unique. We use datestamps, so changing to 20250428