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powerpc64*: use --with-long-double-format=ieee#170215

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Apr 16, 2023
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powerpc64*: use --with-long-double-format=ieee#170215
vcunat merged 13 commits intostagingfrom
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This has been made possible by #182538.

Description of changes

Use IEEE-standard floating point on powerpc64* instead of IBM-proprietary formats.

Motivation

Standardized floating-point is a good thing.

This PR will fix a lot of package test failures that happen on powerpc64* due to nonstandard floating point.

Background

The GCC wiki has more details on the history here.

Red Hat (i.e. IBM) has tried to do this in each of the last six releases, and finally shipped it in May with Fedora 36. Apparently glibc 2.35 fixes the last blocker.

Twice-vendored copies of gnulib are the root of all evil

Copies of gnulib are vendored within several packages. In fact, gettext vendors gnulib not once, but twice. These copies of gnulib must be updated in order to avoid errors like the following when using IEEE long double on powerpc64le:

gettext>   error: declaration for parameter '__obstack_vprintf_chk' but no such parameter
gettext>   105 | __LDBL_REDIR2_DECL (obstack_vprintf_chk)

The root cause of this problem is related to glibc's elaborate scheme for "redirecting" jumps based on which size of long double is in use; the scheme is part of glibc's claim that changing the semantics and bit-length of long double doesn't count as an ABI change.

The fix has been in gnulib for over a year at this point, but many packages have not had a release since then. Almost all of the projects have upgraded copies of gnulib merged into their git repositories.

Things done
  • Built on platform(s)
    • powerpc64le-linux
    • x86_64-linux: pkgsCross.powernv.stdenvBootstrapTools
  • Tested compilation of all packages that depend on this change
  • Tested basic functionality of all binary files (usually in ./result/bin/)
  • Fits CONTRIBUTING.md.

@ofborg ofborg bot added 10.rebuild-darwin: 0 This PR does not cause any packages to rebuild on Darwin. 10.rebuild-linux: 0 This PR does not cause any packages to rebuild on Linux. labels Apr 25, 2022
@ghost ghost closed this Apr 26, 2022
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@ghost ghost reopened this Jul 24, 2022
@github-actions github-actions bot added 6.topic: kernel The Linux kernel 6.topic: lua Lua is a powerful, efficient, lightweight, embeddable scripting language. 6.topic: nixos Issues or PRs affecting NixOS modules, or package usability issues specific to NixOS 6.topic: python Python is a high-level, general-purpose programming language. 6.topic: ruby A dynamic, open source programming language with a focus on simplicity and productivity. 6.topic: rust General-purpose programming language emphasizing performance, type safety, and concurrency. 6.topic: stdenv Standard environment 6.topic: systemd Software suite that provides an array of system components for Linux operating systems. 8.has: documentation This PR adds or changes documentation 8.has: module (update) This PR changes an existing module in `nixos/` labels Jul 24, 2022
@ofborg ofborg bot added the 2.status: merge conflict This PR has merge conflicts with the target branch label Jul 24, 2022
@ghost ghost mentioned this pull request Jul 24, 2022
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@ghost ghost changed the base branch from master to staging July 24, 2022 21:55
@github-actions github-actions bot removed 8.has: documentation This PR adds or changes documentation 6.topic: kernel The Linux kernel 6.topic: rust General-purpose programming language emphasizing performance, type safety, and concurrency. 6.topic: nixos Issues or PRs affecting NixOS modules, or package usability issues specific to NixOS 8.has: module (update) This PR changes an existing module in `nixos/` 6.topic: lua Lua is a powerful, efficient, lightweight, embeddable scripting language. 6.topic: python Python is a high-level, general-purpose programming language. 6.topic: systemd Software suite that provides an array of system components for Linux operating systems. 6.topic: ruby A dynamic, open source programming language with a focus on simplicity and productivity. labels Jul 24, 2022
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@ghost ghost marked this pull request as draft January 2, 2023 02:54
@ghost ghost marked this pull request as ready for review January 2, 2023 02:55
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Adam Joseph and others added 13 commits April 5, 2023 15:51
gnulib: add gnulib-longdouble-redirect.patch
9eafe43 
This patch adds gnulib-longdouble-redirect.patch, which is a subset of
gnulib commit 776af40e09b476a41073131a90022572f448c189.

This patch must be applied to the copy of gnulib which is vendored
within a few packages, when compiling for platforms that use
longdouble-redirection (a glibc-specific feature).  Without it,
compile failures mentioning "__LDBL_REDIR1_DECL" will occur.

Currently there are two packages which need this patch to their
vendored gnulib: gettext and gnused.  Both projects have merged a
fixed version of gnulib but have not yet made a release with the fix.
We can drop this patch as soon as both of those projects are
version-bumped.
gnused: apply gnulib.passthru.longdouble-redirect-patch
1fa5ff7
gettext: apply gnulib.passthru.longdouble-redirect-patch
810c6c3
@SuperSandro2000
texinfo: apply gnulib.passthru.longdouble-redirect-patch
5d64ebd 
Co-authored-by: Sandro <[email protected]>
@SuperSandro2000
mpfr: add --disable-decimal-float
cee9981 
Co-authored-by: Sandro <[email protected]>
libpipeline: apply gnulib.passthru.longdouble-redirect-patch
e2d44f6
libpipeline: 1.5.4 -> 1.5.6
52cf8fe 
This commit bumps libpipeline and drops the gnulib patch since the
vendored copy of gnulib has been updated.  I avoided squashing this
commit into the previous one since knowing how to patch libpipeline
1.5.4 without upgrading might be useful (for example, in a git bisect
or cherry-pick).
@SuperSandro2000
gcc: if isPower64 && !isMusl use --with-long-double-format=ieee
40f7300 
Use IEEE-standard floating point on `powerpc64le` instead of
IBM-proprietary formats.  The GCC wiki has more details on the history
here:

  https://gcc.gnu.org/wiki/Ieee128PowerPC

Nixpkgs' stdenv has no legacy `powerpc64le` installs to deal with
(stdenv did not bootstrap on powerpc64le until very recenty), so it's
much easier decision for us.

Red Hat (i.e. IBM) has tried to do this in each of the last *six*
releases:

  https://fedoraproject.org/wiki/Changes/PPC64LE_Float128_Transition

they and finally shipped it in May with Fedora 36:

  https://bugzilla.redhat.com/show_bug.cgi?id=1649936

Apparently glibc 2.35 fixes the last blocker.

Co-authored-by: Sandro <[email protected]>
@SuperSandro2000
Revert "goffice: disable tests on powerpc64le"
aeae5ca 
This reverts commit dd2bc2a.

Co-authored-by: Sandro <[email protected]>
glibc: suppress warning about IEEE-standard long double
c5a4cc8
gcc: make --with-long-double-format configurable by targetPlatform.gcc
29b3953
gcc: only pass --with-long-double-format if gcc allows it
deda18b
drop gnused gnulib.passthru.longdouble-redirect-patch
0ce0096 
This reverts commit d455973ece7f51907e86fa4e69947ae0eca6bfa1.
@ghost ghost marked this pull request as draft April 5, 2023 23:04
@github-actions github-actions bot removed the 6.topic: stdenv Standard environment label Apr 5, 2023
@ghost ghost marked this pull request as ready for review April 5, 2023 23:04
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ghost commented Apr 5, 2023

Rebased.

Now that #209870 has merged we have proper isolation of the bootstrapFiles' libraries, so I was able to drop the ugly hack from this PR.

@alyssais alyssais added the 6.topic: exotic Exotic hardware or software platform label Apr 5, 2023
@vcunat vcunat merged commit cdf4c59 into NixOS:staging Apr 16, 2023
@ghost ghost deleted the powerpc64le-use-ieee-long-double branch April 16, 2023 22:27
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ghost commented Apr 16, 2023

Thank you @vcunat!!

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vcunat commented Apr 18, 2023

Patch won't apply in this case:
https://hydra.nixos.org/build/216634943/nixlog/1/tail

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ghost commented Apr 20, 2023

Patch won't apply in this case:
https://hydra.nixos.org/build/216634943/nixlog/1/tail

Testing a fix.

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ghost commented Apr 21, 2023

Patch won't apply in this case:
https://hydra.nixos.org/build/216634943/nixlog/1/tail

Testing a fix.

#227471

@ghost ghost mentioned this pull request May 6, 2023
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@Artturin Artturin mentioned this pull request Jan 29, 2024
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6.topic: exotic Exotic hardware or software platform 10.rebuild-darwin: 501+ This PR causes many rebuilds on Darwin and should normally target the staging branches. 10.rebuild-darwin: 5001+ This PR causes many rebuilds on Darwin and must target the staging branches. 10.rebuild-darwin-stdenv This PR causes stdenv to rebuild on Darwin and must target a staging branch. 10.rebuild-linux: 501+ This PR causes many rebuilds on Linux and should normally target the staging branches. 10.rebuild-linux: 5001+ This PR causes many rebuilds on Linux and must target the staging branches. 10.rebuild-linux-stdenv This PR causes stdenv to rebuild on Linux and must target a staging branch.

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@tlaurion @CrystalGamma @madscientist159 @minijackson @vcunat @SuperSandro2000 @alyssais