nixpkgs/pkgs/build-support/lib/meson.nix
Raito Bezarius d4c673a92b build-support/meson: explicitly use ambiant CMake during cross compilation
Thanks to Qyriad, it was found out that Nixpkgs was unable to cross
compile when CMake was needed at cross compilation time with Meson
because Meson refuse to use the ambiant CMake.

A simple fix is to always provide the ambiant CMake and trust the
packager to pass the right CMake, otherwise the rest of the build would
probably fail in mysterious ways.

An example of package that required this fix is the Lix, a Nix
implementation, that uses `toml11` discovered via CMake during the Meson
configure phase.

Co-authored-by: Qyriad <qyriad@qyriad.me>
Signed-off-by: Raito Bezarius <masterancpp@gmail.com>
2024-05-11 13:32:14 +02:00

39 lines
1.4 KiB
Nix

{ stdenv, lib }:
let
inherit (lib) boolToString optionals;
# See https://mesonbuild.com/Reference-tables.html#cpu-families
cpuFamily = platform: with platform;
/**/ if isAarch32 then "arm"
else if isx86_32 then "x86"
else platform.uname.processor;
crossFile = builtins.toFile "cross-file.conf" ''
[properties]
bindgen_clang_arguments = ['-target', '${stdenv.targetPlatform.config}']
needs_exe_wrapper = ${boolToString (!stdenv.buildPlatform.canExecute stdenv.hostPlatform)}
[host_machine]
system = '${stdenv.targetPlatform.parsed.kernel.name}'
cpu_family = '${cpuFamily stdenv.targetPlatform}'
cpu = '${stdenv.targetPlatform.parsed.cpu.name}'
endian = ${if stdenv.targetPlatform.isLittleEndian then "'little'" else "'big'"}
[binaries]
llvm-config = 'llvm-config-native'
rust = ['rustc', '--target', '${stdenv.targetPlatform.rust.rustcTargetSpec}']
# Meson refuses to consider any CMake binary during cross compilation if it's
# not explicitly specified here, in the cross file.
# https://github.com/mesonbuild/meson/blob/0ed78cf6fa6d87c0738f67ae43525e661b50a8a2/mesonbuild/cmake/executor.py#L72
cmake = 'cmake'
'';
crossFlags = optionals (stdenv.hostPlatform != stdenv.buildPlatform) [ "--cross-file=${crossFile}" ];
makeMesonFlags = { mesonFlags ? [], ... }: crossFlags ++ mesonFlags;
in
{
inherit makeMesonFlags;
}