The new time-machine commit is Guix v1.2.0 with a yet-unupstreamed patch
for NSIS.
A few important changes:
1. Guix switched back from using CPATH to C{,PLUS}_INCLUDE_PATH as the
way to indicate #include search paths.
2. GCC's library is now split into a separate output, whereas before it
was included in the default output. This means that our gcc toolchain
packages need to propagate that output.
3. A few package versions were bumped
When building nsis, if VERSION is not specified, it defaults to
cvs_version which is non-deterministic as it includes the current date.
This patches nsis to default to SOURCE_DATE_EPOCH if it exists so that
nsis is reproducible.
Upstream change: https://github.com/kichik/nsis/pull/13
The libtool unsorted 'find' determinism issue seemed to have been solved
in gcc-9's git: d41cd173e23ebea7c758644d6ad6e0fde1c2e3a6 or SVN: r262451
Furthermore, it seems that Ubuntu Focal 20.04 LTS is going to ship with
gcc 9 and mingw-w64 7, which will match what we have now.
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A note on this:
Careful observers will see that previously I stated that all released
versions of gcc were bootstrapped with a libtool 2.2.7a, meaning that
they all had the unsorted 'find' determinism issue first resolved in
libtool 2.2.7b.
However, I was mistaken, gcc's ltmain.sh CLAIMS it was generated by
libtool 2.2.7a, but it was in fact edited manually. It seems that gcc
maintains their own versions of ltmain.sh and libtool.m4, and only
sometimes backports patches from upstream.
Quite confusing.
Previously, Guix would produce a gcc which did not know to use the SSP
function from glibc, and required a gcc make flag for it to do so, in my
attempt to fix it upstream I realized that this is no longer the case.
This can be verified by performing a Guix build and doing
readelf -s ... | grep __stack_chk
to check that symbols are coming from glibc, and doing
readelf -d ... | grep NEEDED | grep ssp
to see that libssp.so is not being depended on
- Clearer and more accurate prose
- Pin `guix pull' to commit rather than branch
- Just use `use-module' instead of `define-module'
- Use `bash-minimal' instead of `bash'
- Remove unneeded `tcsh' from manifest
- Explicitly use `python-3.7'
- Add comments about how {native,cross}-toolchains are produced and
why
Carl Dong