llvm6: musl compat

pkgs/development/compilers/llvm/6/clang/default.nix

@@ -47,6 +47,8 @@ let
 
       # Patch for standalone doc building
       sed -i '1s,^,find_package(Sphinx REQUIRED)\n,' docs/CMakeLists.txt
+    '' + stdenv.lib.optionalString stdenv.hostPlatform.isMusl ''
+      sed -i -e 's/lgcc_s/lgcc_eh/' lib/Driver/ToolChains/*.cpp
     '';
 
     outputs = [ "out" "lib" "python" ];

pkgs/development/compilers/llvm/6/libc++/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetch, cmake, llvm, libcxxabi, fixDarwinDylibNames, version }:
+{ lib, stdenv, fetch, cmake, python, llvm, libcxxabi, fixDarwinDylibNames, version }:
 
 stdenv.mkDerivation rec {
   name = "libc++-${version}";
@@ -10,6 +10,12 @@ stdenv.mkDerivation rec {
     export LIBCXXABI_INCLUDE_DIR="$PWD/$(ls -d libcxxabi-${version}*)/include"
   '';
 
+  # on next rebuild, this can be replaced with optionals; for now set to null to avoid
+  # patches = stdenv.lib.optionals stdenv.hostPlatform.isMusl [
+  patches = if stdenv.hostPlatform.isMusl then [
+    ../../libcxx-0001-musl-hacks.patch
+  ] else null;
+
   prePatch = ''
     substituteInPlace lib/CMakeLists.txt --replace "/usr/lib/libc++" "\''${LIBCXX_LIBCXXABI_LIB_PATH}/libc++"
   '';
@@ -17,9 +23,10 @@ stdenv.mkDerivation rec {
   preConfigure = ''
     # Get headers from the cxxabi source so we can see private headers not installed by the cxxabi package
     cmakeFlagsArray=($cmakeFlagsArray -DLIBCXX_CXX_ABI_INCLUDE_PATHS="$LIBCXXABI_INCLUDE_DIR")
+  '' + lib.optionalString stdenv.hostPlatform.isMusl ''
+    patchShebangs utils/cat_files.py
   '';
-
+  nativeBuildInputs = [ cmake ] ++ stdenv.lib.optional stdenv.hostPlatform.isMusl python;
-  nativeBuildInputs = [ cmake ];
 
   buildInputs = [ libcxxabi ] ++ lib.optional stdenv.isDarwin fixDarwinDylibNames;
 
@@ -27,7 +34,7 @@ stdenv.mkDerivation rec {
     "-DLIBCXX_LIBCXXABI_LIB_PATH=${libcxxabi}/lib"
     "-DLIBCXX_LIBCPPABI_VERSION=2"
     "-DLIBCXX_CXX_ABI=libcxxabi"
-  ];
+  ] ++ stdenv.lib.optional stdenv.hostPlatform.isMusl "-DLIBCXX_HAS_MUSL_LIBC=1";
 
   enableParallelBuilding = true;
 

pkgs/development/compilers/llvm/6/libc++abi.nix

@@ -14,6 +14,8 @@ stdenv.mkDerivation {
     export cmakeFlags="-DLLVM_PATH=$PWD/$(ls -d llvm-*) -DLIBCXXABI_LIBCXX_PATH=$PWD/$(ls -d libcxx-*)"
   '' + stdenv.lib.optionalString stdenv.isDarwin ''
     export TRIPLE=x86_64-apple-darwin
+  '' + stdenv.lib.optionalString stdenv.hostPlatform.isMusl ''
+    patch -p1 -d $(ls -d libcxx-*) -i ${../libcxx-0001-musl-hacks.patch}
   '';
 
   installPhase = if stdenv.isDarwin

pkgs/development/compilers/llvm/6/llvm.nix

@@ -74,6 +74,11 @@ in stdenv.mkDerivation (rec {
 
     # Revert compiler-rt commit that makes codesign mandatory
     patch -p1 -i ${./compiler-rt-codesign.patch} -d projects/compiler-rt
+  '' + stdenv.lib.optionalString stdenv.hostPlatform.isMusl ''
+    patch -p1 -i ${../TLI-musl.patch}
+    substituteInPlace unittests/Support/CMakeLists.txt \
+      --replace "add_subdirectory(DynamicLibrary)" ""
+    rm unittests/Support/DynamicLibrary/DynamicLibraryTest.cpp
   '';
 
   # hacky fix: created binaries need to be run before installation
@@ -104,6 +109,14 @@ in stdenv.mkDerivation (rec {
   ++ stdenv.lib.optionals (isDarwin) [
     "-DLLVM_ENABLE_LIBCXX=ON"
     "-DCAN_TARGET_i386=false"
+  ]
+  ++ stdenv.lib.optionals stdenv.hostPlatform.isMusl [
+    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
+    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.targetPlatform.config}"
+    "-DTARGET_TRIPLE=${stdenv.targetPlatform.config}"
+
+    "-DCOMPILER_RT_BUILD_SANITIZERS=OFF"
+    "-DCOMPILER_RT_BUILD_XRAY=OFF"
   ];
 
   postBuild = ''