llvmPackages_*.libllvm: make llvm-config and llvm-config equivalent

LLVM's build system creates NATIVE/bin/llvm-config by reexecuting cmake with entirely new flags. Problematically, the `CMAKE_INSTALL_*` flags are not inherited, causing llvm-config-native to return wrong installation paths, e. g. CMAKE_INSTALL_LIBDIR would default to `lib64` on x86_64-linux. Previously this was masked by outputs.patch which replaced ActiveLibDir with a string passed in from Nix, however `--cmakedir` for example would turn out to be wrong always, breaking cross-compilation of e. g. lld. Additionally LLVM_ENABLE_RTTI needs to be repassed, as it is used to determine if RTTI is available. Passing LLVM_LINK_LLVM_DYLIB is crucial if we are building LLVM non-statically: It influences the --shared-mode flag (which should indicate that -lLLVM is enough to link all components) and makes --link-shared work in the first place, i. e. llvm-config-native believes the built shared libs don't exist unless we repass this flag. Passing LLVM_LINK_LLVM_DYLIB=ON, however, makes the native build produce a full libLLVM.so which is something we don't want, so we introduce a patch which forces llvm-config to link statically against the LLVM components it needs.
2026-10-02 04:50:21 +00:00 · 2021-12-31 13:46:48 +01:00
parent 677a94fd9e
commit e10edcc278
11 changed files with 375 additions and 60 deletions
--- a/pkgs/development/compilers/llvm/10/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/10/llvm/default.nix
@@ -57,6 +57,12 @@ in stdenv.mkDerivation (rec {
  propagatedBuildInputs = [ ncurses zlib ];

  patches = [
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch
    # On older CPUs (e.g. Hydra/wendy) we'd be getting an error in this test.
    (fetchpatch {
@@ -125,18 +131,28 @@ in stdenv.mkDerivation (rec {
    ln -sv $PWD/lib $out
  '';

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -162,7 +178,21 @@ in stdenv.mkDerivation (rec {
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/11/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/11/llvm/default.nix
@@ -57,6 +57,12 @@ in stdenv.mkDerivation (rec {
  propagatedBuildInputs = [ ncurses zlib ];

  patches = [
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch
    # On older CPUs (e.g. Hydra/wendy) we'd be getting an error in this test.
    (fetchpatch {
@@ -126,18 +132,28 @@ in stdenv.mkDerivation (rec {
  # E.g. mesa.drivers use the build-id as a cache key (see #93946):
  LDFLAGS = optionalString (enableSharedLibraries && !stdenv.isDarwin) "-Wl,--build-id=sha1";

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -163,7 +179,21 @@ in stdenv.mkDerivation (rec {
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/12/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/12/llvm/default.nix
@@ -58,6 +58,12 @@ in stdenv.mkDerivation (rec {
    ++ [ zlib ];

  patches = [
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch
    # On older CPUs (e.g. Hydra/wendy) we'd be getting an error in this test.
    (fetchpatch {
@@ -111,18 +117,28 @@ in stdenv.mkDerivation (rec {
  # E.g. mesa.drivers use the build-id as a cache key (see #93946):
  LDFLAGS = optionalString (enableSharedLibraries && !stdenv.isDarwin) "-Wl,--build-id=sha1";

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -148,7 +164,21 @@ in stdenv.mkDerivation (rec {
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/13/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/13/llvm/default.nix
@@ -52,6 +52,12 @@ in stdenv.mkDerivation (rec {
  checkInputs = [ which ];

  patches = [
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch

    # Fix random compiler crashes: https://bugs.llvm.org/show_bug.cgi?id=50611
@@ -104,18 +110,28 @@ in stdenv.mkDerivation (rec {
  # E.g. mesa.drivers use the build-id as a cache key (see #93946):
  LDFLAGS = optionalString (enableSharedLibraries && !stdenv.isDarwin) "-Wl,--build-id=sha1";

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -141,7 +157,21 @@ in stdenv.mkDerivation (rec {
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/5/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/5/llvm/default.nix
@@ -65,6 +65,13 @@ stdenv.mkDerivation ({
    #  sha256 = "0injj1hqgrbcbihhwp2nbal88jfykad30r54f2cdcx7gws2fcy8i";
    #  stripLen = 1;
    #})
+
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch

    # Fix invalid std::string(nullptr) for GCC 12
@@ -103,20 +110,30 @@ stdenv.mkDerivation ({
    ln -sv $PWD/lib $out
  '';

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"

    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DTARGET_TRIPLE=${stdenv.hostPlatform.config}"
  ]
-  ++ lib.optional enableSharedLibraries
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ++ lib.optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -143,7 +160,21 @@ stdenv.mkDerivation ({
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/6/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/6/llvm/default.nix
@@ -63,6 +63,13 @@ stdenv.mkDerivation ({
      includes = [ "test/tools/gold/X86/common.ll" ];
      sha256 = "0fxgrxmfnjx17w3lcq19rk68b2xksh1bynz3ina784kma7hp4wdb";
    })
+
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch

    # Fix invalid std::string(nullptr) for GCC 12
@@ -96,19 +103,29 @@ stdenv.mkDerivation ({
    ln -sv $PWD/lib $out
  '';

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=WebAssembly"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -134,7 +151,21 @@ stdenv.mkDerivation ({
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/7/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/7/llvm/default.nix
@@ -67,6 +67,13 @@ in stdenv.mkDerivation ({
      url = "https://github.com/llvm-mirror/llvm/commit/cc1f2a595ead516812a6c50398f0f3480ebe031f.patch";
      sha256 = "0k6k1p5yisgwx417a67s7sr9930rqh1n0zv5jvply8vjjy4b3kf8";
    })
+
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch

    # Fix invalid std::string(nullptr) for GCC 12
@@ -113,19 +120,29 @@ in stdenv.mkDerivation ({
    ln -sv $PWD/lib $out
  '';

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=WebAssembly"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -151,7 +168,21 @@ in stdenv.mkDerivation ({
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/8/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/8/llvm/default.nix
@@ -57,6 +57,12 @@ in stdenv.mkDerivation ({
  propagatedBuildInputs = [ ncurses zlib ];

  patches = [
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    # Fix missing includes for GCC 10
    (fetchpatch {
      url = "https://bugs.gentoo.org/attachment.cgi?id=612792";
@@ -107,18 +113,28 @@ in stdenv.mkDerivation ({
    ln -sv $PWD/lib $out
  '';

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -144,7 +160,21 @@ in stdenv.mkDerivation ({
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/9/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/9/llvm/default.nix
@@ -57,6 +57,12 @@ in stdenv.mkDerivation (rec {
  propagatedBuildInputs = [ ncurses zlib ];

  patches = [
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch
    # Force a test to evaluate the saved benchmark for a CPU for which LLVM has
    # an execution model. See NixOS/nixpkgs#119673.
@@ -122,18 +128,28 @@ in stdenv.mkDerivation (rec {
    ln -sv $PWD/lib $out
  '';

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -159,7 +175,21 @@ in stdenv.mkDerivation (rec {
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/git/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/git/llvm/default.nix
@@ -51,6 +51,12 @@ in stdenv.mkDerivation (rec {
  checkInputs = [ which ];

  patches = [
+    # When cross-compiling we configure llvm-config-native with an approximation
+    # of the flags used for the normal LLVM build. To avoid the need for building
+    # a native libLLVM.so (which would fail) we force llvm-config to be linked
+    # statically against the necessary LLVM components always.
+    ../../llvm-config-link-static.patch
+
    ./gnu-install-dirs.patch
  ] ++ lib.optional enablePolly ./gnu-install-dirs-polly.patch;

@@ -96,18 +102,28 @@ in stdenv.mkDerivation (rec {
  # E.g. mesa.drivers use the build-id as a cache key (see #93946):
  LDFLAGS = optionalString (enableSharedLibraries && !stdenv.isDarwin) "-Wl,--build-id=sha1";

-  cmakeFlags = with stdenv; [
-    "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+  cmakeFlags = with stdenv; let
+    # These flags influence llvm-config's BuildVariables.inc in addition to the
+    # general build. We need to make sure these are also passed via
+    # CROSS_TOOLCHAIN_FLAGS_NATIVE when cross-compiling or llvm-config-native
+    # will return different results from the cross llvm-config.
+    #
+    # Some flags don't need to be repassed because LLVM already does so (like
+    # CMAKE_BUILD_TYPE), others are irrelevant to the result.
+    flagsForLlvmConfig = [
+      "-DLLVM_INSTALL_CMAKE_DIR=${placeholder "dev"}/lib/cmake/llvm/"
+      "-DLLVM_ENABLE_RTTI=ON"
+    ] ++ optionals enableSharedLibraries [
+      "-DLLVM_LINK_LLVM_DYLIB=ON"
+    ];
+  in flagsForLlvmConfig ++ [
    "-DCMAKE_BUILD_TYPE=${if debugVersion then "Debug" else "Release"}"
    "-DLLVM_INSTALL_UTILS=ON"  # Needed by rustc
    "-DLLVM_BUILD_TESTS=ON"
    "-DLLVM_ENABLE_FFI=ON"
-    "-DLLVM_ENABLE_RTTI=ON"
    "-DLLVM_HOST_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_DEFAULT_TARGET_TRIPLE=${stdenv.hostPlatform.config}"
    "-DLLVM_ENABLE_DUMP=ON"
-  ] ++ optionals enableSharedLibraries [
-    "-DLLVM_LINK_LLVM_DYLIB=ON"
  ] ++ optionals enableManpages [
    "-DLLVM_BUILD_DOCS=ON"
    "-DLLVM_ENABLE_SPHINX=ON"
@@ -133,7 +149,21 @@ in stdenv.mkDerivation (rec {
          "-DCMAKE_STRIP=${nativeBintools}/bin/${nativeBintools.targetPrefix}strip"
          "-DCMAKE_RANLIB=${nativeBintools}/bin/${nativeBintools.targetPrefix}ranlib"
        ];
-      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list=${lib.concatStringsSep ";" nativeToolchainFlags}"
+        # We need to repass the custom GNUInstallDirs values, otherwise CMake
+        # will choose them for us, leading to wrong results in llvm-config-native
+        nativeInstallFlags = [
+          "-DCMAKE_INSTALL_PREFIX=${placeholder "out"}"
+          "-DCMAKE_INSTALL_BINDIR=${placeholder "out"}/bin"
+          "-DCMAKE_INSTALL_INCLUDEDIR=${placeholder "dev"}/include"
+          "-DCMAKE_INSTALL_LIBDIR=${placeholder "lib"}/lib"
+          "-DCMAKE_INSTALL_LIBEXECDIR=${placeholder "lib"}/libexec"
+        ];
+      in "-DCROSS_TOOLCHAIN_FLAGS_NATIVE:list="
+      + lib.concatStringsSep ";" (lib.concatLists [
+        flagsForLlvmConfig
+        nativeToolchainFlags
+        nativeInstallFlags
+      ])
    )
  ];

--- a/pkgs/development/compilers/llvm/llvm-config-link-static.patch
+++ b/pkgs/development/compilers/llvm/llvm-config-link-static.patch
@@ -0,0 +1,12 @@
+diff --git llvm/tools/llvm-config/CMakeLists.txt llvm/tools/llvm-config/CMakeLists.txt
+index 16ba54c0cf2f..20b017195e84 100644
+--- llvm/tools/llvm-config/CMakeLists.txt
+++ llvm/tools/llvm-config/CMakeLists.txt
+@@ -6,6 +6,7 @@ set(BUILDVARIABLES_OBJPATH ${CMAKE_CURRENT_BINARY_DIR}/BuildVariables.inc)
+ # Add the llvm-config tool.
+ add_llvm_tool(llvm-config
+   llvm-config.cpp
+  DISABLE_LLVM_LINK_LLVM_DYLIB
+   )
+ 
+ # Compute the substitution values for various items.