Skip to content

Commit

Permalink
pkgsMusl.haskell.compiler.ghc8102Binary: Fix musl segfault. Fixes Nix…
Browse files Browse the repository at this point in the history 
…OS#118731 NixOS#129247.

This commit replaces the musl + glibc hackery in the GHC bindist
compiler by using the new musl based bindist that GHC HQ provides
(built on Alpine).
We could alternatively also use a nix-built musl boostrap compiler,
but it seems nicer to use the GHC HQ one for now.

This fixes the compiler built by
`pkgsMusl.haskell.compiler.ghc8102Binary` segfaulting (NixOS#118731)
since the commit

    5e2311d - musl: 1.2.1 -> 1.2.2

concretely, musl commit

    01c7920f - remove redundant pthread struct members repeated for layout purposes

which I suspect breaks some glibc/musl ABI compatibility that may have
existed accidentally until then.

The added

    lib.optional stdenv.targetPlatform.isMusl "pie";

also fixes that the packaged bindist compiler cannot create a binary
in its `installCheck` phase (and overall); see detail explanation
in NixOS#129247.
  • Loading branch information
@nh2
nh2 committed Jul 4, 2021
1 parent 795cf00 commit 9aabdea
Showing 1 changed file with 76 additions and 29 deletions.
105 changes: 76 additions & 29 deletions pkgs/development/compilers/ghc/8.10.2-binary.nix
View file
Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
{ lib, stdenv
, fetchurl, perl, gcc
, ncurses5
, ncurses6, gmp, glibc, libiconv, numactl
, ncurses6, gmp, libiconv, numactl
, llvmPackages

# minimal = true; will remove files that aren't strictly necessary for
Expand Down Expand Up @@ -49,16 +49,33 @@ let
{ nixPackage = ncurses5; fileToCheckFor = "libtinfo.so.5"; }
];
};
x86_64-linux = {
src = {
url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-deb10-linux.tar.xz";
sha256 = "0chnzy9j23b2wa8clx5arwz8wnjfxyjmz9qkj548z14cqf13slcl";
};
exePathForLibraryCheck = "ghc/stage2/build/tmp/ghc-stage2";
archSpecificLibraries = [
{ nixPackage = ncurses6; fileToCheckFor = "libtinfo.so.6"; }
];
};
x86_64-linux =
if stdenv.hostPlatform.isMusl
then
{ # musl-bindist (referred to below)
src = {
url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-alpine3.10-linux-integer-simple.tar.xz";
sha256 = "0xpcbyaxqyhbl6f0i3s4rp2jm67nqpkfh2qlbj3i2fiaix89ml0l";
};
exePathForLibraryCheck = "bin/ghc";
archSpecificLibraries = [
# In contrast to glibc builds, the musl-bindist uses `libncursesw.so.*`
# instead of `libtinfo.so.*.`
{ nixPackage = ncurses6; fileToCheckFor = "libncursesw.so.6"; }
];
}
else
{ # normal glibc based bindist
src = {
url = "${downloadsUrl}/${version}/ghc-${version}-x86_64-deb10-linux.tar.xz";
sha256 = "0chnzy9j23b2wa8clx5arwz8wnjfxyjmz9qkj548z14cqf13slcl";
};
exePathForLibraryCheck = "ghc/stage2/build/tmp/ghc-stage2";
archSpecificLibraries = [
{ nixPackage = ncurses6; fileToCheckFor = "libtinfo.so.6"; }
];
}
;
armv7l-linux = {
src = {
url = "${downloadsUrl}/${version}/ghc-${version}-armv7-deb10-linux.tar.xz";
Expand Down Expand Up @@ -110,12 +127,6 @@ let
libEnvVar = lib.optionalString stdenv.hostPlatform.isDarwin "DY"
+ "LD_LIBRARY_PATH";

glibcDynLinker = assert stdenv.isLinux;
if stdenv.hostPlatform.libc == "glibc" then
# Could be stdenv.cc.bintools.dynamicLinker, keeping as-is to avoid rebuild.
''"$(cat $NIX_CC/nix-support/dynamic-linker)"''
else
"${lib.getLib glibc}/lib/ld-linux*";
in

stdenv.mkDerivation rec {
Expand All @@ -126,7 +137,20 @@ stdenv.mkDerivation rec {
src = fetchurl binDistUsed.src;

nativeBuildInputs = [ perl ];
propagatedBuildInputs = lib.optionals useLLVM [ llvmPackages.llvm ];
propagatedBuildInputs =
lib.optionals useLLVM [ llvmPackages.llvm ]
# Because musl bindists currently provide no way to tell where
# libgmp is (see not [musl bindists have no .buildinfo]), we need
# to propagate `gmp`, otherwise programs built by this ghc will
# fail linking with `cannot find -lgmp` errors.
# Also, as of writing, the release pages of musl bindists claim
# that they use `integer-simple` and do not require `gmp`; however
# that is incorrect, so `gmp` is required until a release has been
# made that includes https://gitlab.haskell.org/ghc/ghc/-/issues/20059.
# (Note that for packaging the `-binary` compiler, nixpkgs does not care
# about whether or not `gmp` is used; this comment is just here to explain
# why the `gmp` dependency exists despite what the release page says.)
++ lib.optionals stdenv.hostPlatform.isMusl [ gmp ]; # musl bindist needs this

# Set LD_LIBRARY_PATH or equivalent so that the programs running as part
# of the bindist installer can find the libraries they expect.
Expand Down Expand Up @@ -187,6 +211,9 @@ stdenv.mkDerivation rec {
patchShebangs ghc-${version}/configure
'' +
# We have to patch the GMP paths for the integer-gmp package.
# Note [musl bindists have no .buildinfo]
# Note that musl bindists do not contain them; unclear if that's intended;
# see: https://gitlab.haskell.org/ghc/ghc/-/issues/20073#note_363231
''
find . -name integer-gmp.buildinfo \
-exec sed -i "s@extra-lib-dirs: @extra-lib-dirs: ${gmp.out}/lib@" {} \;
Expand All @@ -203,16 +230,7 @@ stdenv.mkDerivation rec {
# Rename needed libraries and binaries, fix interpreter
lib.optionalString stdenv.isLinux ''
find . -type f -perm -0100 -exec patchelf \
--interpreter ${glibcDynLinker} {} \;
'' +
# We're kludging a glibc bindist into working with non-glibc...
# Here we patch up the use of `__strdup` (part of glibc binary ABI)
# to instead use `strdup` since musl doesn't provide __strdup
# (`__strdup` is defined to be an alias of `strdup` anyway[1]).
# [1] http://refspecs.linuxbase.org/LSB_4.0.0/LSB-Core-generic/LSB-Core-generic/baselib---strdup-1.html
# Use objcopy magic to make the change:
lib.optionalString stdenv.hostPlatform.isMusl ''
find ./ghc-${version}/rts -name "libHSrts*.a" -exec ''${OBJCOPY:-objcopy} --redefine-sym __strdup=strdup {} \;
--interpreter ${stdenv.cc.bintools.dynamicLinker} {} \;
'';

# fix for `configure: error: Your linker is affected by binutils #16177`
Expand All @@ -222,6 +240,9 @@ stdenv.mkDerivation rec {

configurePlatforms = [ ];
configureFlags = [
# Note that musl-based bindists seem to do nothing with the
# `--with-gmp-libraries` flag, see:
# https://gitlab.haskell.org/ghc/ghc/-/issues/20073#note_363231
"--with-gmp-libraries=${lib.getLib gmp}/lib"
"--with-gmp-includes=${lib.getDev gmp}/include"
] ++ lib.optional stdenv.isDarwin "--with-gcc=${./gcc-clang-wrapper.sh}"
Expand All @@ -232,6 +253,22 @@ stdenv.mkDerivation rec {
# calls install-strip ...
dontBuild = true;

# Apparently necessary for the ghc Alpine (musl) bindist:
# When we strip, and then run the
# patchelf --set-rpath "${libPath}:$(patchelf --print-rpath $p)" $p
# below, running ghc (e.g. during `installCheckPhase)` gives some apparently
# corrupted rpath or whatever makes the loader work on nonsensical strings:
# running install tests
# Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: : symbol not found
# Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: ir6zf6c9f86pfx8sr30n2vjy-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/../lib/x86_64-linux-ghc-8.10.5/libHSexceptions-0.10.4-ghc8.10.5.so: symbol not found
# Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: y/lib/ghc-8.10.5/bin/../lib/x86_64-linux-ghc-8.10.5/libHStemplate-haskell-2.16.0.0-ghc8.10.5.so: symbol not found
# Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: 8.10.5/libHStemplate-haskell-2.16.0.0-ghc8.10.5.so: symbol not found
# Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: �: symbol not found
# Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: �?: symbol not found
# Error relocating /nix/store/...-ghc-8.10.2-binary/lib/ghc-8.10.5/bin/ghc: 64-linux-ghc-8.10.5/libHSexceptions-0.10.4-ghc8.10.5.so: symbol not found
# This is extremely bogus and should be investigated.
dontStrip = if stdenv.hostPlatform.isMusl then true else false; # `if` for explicitness

# On Linux, use patchelf to modify the executables so that they can
# find editline/gmp.
postFixup = lib.optionalString stdenv.isLinux
Expand Down Expand Up @@ -279,13 +316,23 @@ stdenv.mkDerivation rec {
find $out -type f -name '*.p_o' -delete
find $out -type f -name '*.p_hi' -delete
find $out -type f -name '*_p.a' -delete
rm $out/lib/ghc-*/bin/ghc-iserv-prof
# `-f` because e.g. musl bindist does not have this file.
rm -f $out/lib/ghc-*/bin/ghc-iserv-prof
# Hydra will redistribute this derivation, so we have to keep the docs for
# legal reasons (retaining the legal notices etc)
# As a last resort we could unpack the docs separately and symlink them in.
# They're in $out/share/{doc,man}.
'';

# In nixpkgs, musl based builds currently enable `pie` hardening by default
# (see `defaultHardeningFlags` in `make-derivation.nix`).
# But GHC cannot currently produce outputs that are ready for `-pie` linking.
# Thus, disable `pie` hardening, otherwise `recompile with -fPIE` errors appear.
# See:
# * https://github.com/NixOS/nixpkgs/issues/129247
# * https://gitlab.haskell.org/ghc/ghc/-/issues/19580
hardeningDisable = lib.optional stdenv.targetPlatform.isMusl "pie";

doInstallCheck = true;
installCheckPhase = ''
unset ${libEnvVar}
Expand Down

0 comments on commit 9aabdea

Please sign in to comment.