nixpkgs/pkgs/development/compilers/llvm/16/libunwind/default.nix
Peter Waller 6ba1b5b0b3 llvmPackages_15, llvmPackages_16: Make the pkgsLLVM.stdenv work
What changed:

* Fixed crtbeginS.o and crtendS.o missing
  (they may or may not be called crt{begin_end},{,_shared}.

* Fixed implicit function declaration causing build errors for various
  builds by supplying -Wno-implicit-function-declaration.

* Fixed __cxxabi_config.h missing, by adding -I${cxxabi}/include/c++/v1
  in the wrapper.

* Fixed libcxx failing to build due to missing libunwind symbols by
  including libunwind as a buildInput, and setting
  -DLIBCXX_ADDITIONAL_LIBRARIES=unwind for stdenv.hostPlatform.useLLVM == true.

* libcxxabi wants to find libunwind at libunwind_shared.so, so symlink
  it there in libunwind.

* llvmPackages_16.libcxxabi: Pass -nostdlib via CMAKE_*_LINKER_FLAGS

  Without this flag, the link of libcxxabi.so tries to pull in libgcc and
  friends, from the clang compiler driver.

* Drop unneeded musl hack patch from libcxx.

* Pass -Wno-error=implicit-function-declaration only to compiler-rt

  See LLVM forum discussion:

  https://discourse.llvm.org/t/configure-script-breakage-with-the-new-werror-implicit-function-declaration/65213

  In summary, LLVM 16 made implicit function declaration an error. This
  happens a lot in configure scripts which can break things.

* llvmPackages_16: !isDarwin: Supply -DLIBCXX_ABI_USE_LLVM_UNWINDER=On

  Otherwise it fails with various undefined references to _Unwind_*
  functions: (full list: _Unwind_DeleteException _Unwind_GetIP
  _Unwind_GetLanguageSpecificData _Unwind_GetRegionStart
  _Unwind_RaiseException _Unwind_Resume _Unwind_SetGR _Unwind_SetIP).

* 16.libcxxabi: Only pass -nostdlib for useLLVM and Darwin builds

What was tested:

* x86_64-linux, aarch64-linux, the stdenv builds.
  * Additionally I was able to get nix to build, with an overlay to fix
    a couple of minor issues in downstream packages (overlay supplied in
    PR #246577.

* aarch64-darwin fails spuriously in a single LLVM test
  strip-preserve-atime.test checking atime timestamps.

* The same for pkgsLLVM with llvmPackages = llvmPackages_15.

Signed-off-by: Peter Waller <p@pwaller.net>
2023-08-22 17:33:24 +01:00

68 lines
1.9 KiB
Nix

{ lib, stdenv, llvm_meta, version
, monorepoSrc, runCommand
, cmake
, ninja
, python3
, enableShared ? !stdenv.hostPlatform.isStatic
}:
stdenv.mkDerivation rec {
pname = "libunwind";
inherit version;
# I am not so comfortable giving libc++ and friends the whole monorepo as
# requested, so I filter it to what is needed.
src = runCommand "${pname}-src-${version}" {} ''
mkdir -p "$out"
cp -r ${monorepoSrc}/cmake "$out"
cp -r ${monorepoSrc}/${pname} "$out"
mkdir -p "$out/libcxx"
cp -r ${monorepoSrc}/libcxx/cmake "$out/libcxx"
cp -r ${monorepoSrc}/libcxx/utils "$out/libcxx"
mkdir -p "$out/llvm"
cp -r ${monorepoSrc}/llvm/cmake "$out/llvm"
cp -r ${monorepoSrc}/llvm/utils "$out/llvm"
cp -r ${monorepoSrc}/runtimes "$out"
'';
sourceRoot = "${src.name}/runtimes";
prePatch = ''
cd ../${pname}
chmod -R u+w .
'';
patches = [
./gnu-install-dirs.patch
];
postPatch = ''
cd ../runtimes
'';
postInstall = lib.optionalString (enableShared && !stdenv.hostPlatform.isDarwin) ''
# libcxxabi wants to link to libunwind_shared.so (?).
ln -s $out/lib/libunwind.so $out/lib/libunwind_shared.so
'';
outputs = [ "out" "dev" ];
nativeBuildInputs = [ cmake ninja python3 ];
cmakeFlags = [
"-DLLVM_ENABLE_RUNTIMES=libunwind"
] ++ lib.optional (!enableShared) "-DLIBUNWIND_ENABLE_SHARED=OFF";
meta = llvm_meta // {
# Details: https://github.com/llvm/llvm-project/blob/main/libunwind/docs/index.rst
homepage = "https://clang.llvm.org/docs/Toolchain.html#unwind-library";
description = "LLVM's unwinder library";
longDescription = ''
The unwind library provides a family of _Unwind_* functions implementing
the language-neutral stack unwinding portion of the Itanium C++ ABI (Level
I). It is a dependency of the C++ ABI library, and sometimes is a
dependency of other runtimes.
'';
};
}