rust-llvm: Make llvm-config cross compile friendly

Import patches from clang layer to ensure that llvm-config
can be provided configs from environment

Signed-off-by: Khem Raj <raj.khem@gmail.com>

recipes-devtools/rust/rust-llvm.inc

@@ -14,6 +14,9 @@ DEPENDS += "ninja-native rust-llvm-native"
 ARM_INSTRUCTION_SET_armv5 = "arm"
 ARM_INSTRUCTION_SET_armv4t = "arm"
 
+LLVM_RELEASE = "6.0"
+LLVM_DIR = "llvm${LLVM_RELEASE}"
+
 EXTRA_OECMAKE = " \
     -DCMAKE_BUILD_TYPE=Release \
     -DLLVM_TARGETS_TO_BUILD='X86;ARM;AArch64;PowerPC;Mips' \
@@ -41,21 +44,6 @@ EXTRA_OECMAKE_append_class-target = "\
 # provide almost no value. If you really need them then override this
 INHIBIT_PACKAGE_DEBUG_SPLIT = "1"
 
-do_compile_prepend_class-target() {
-    # Fix paths in llvm-config
-    sed -i "s|sys::path::parent_path(CurrentPath))\.str()|sys::path::parent_path(sys::path::parent_path(CurrentPath))).str()|g" ${S}/tools/llvm-config/llvm-config.cpp
-
-    # Fix the hardcoded libdir in llvm-config
-    sed -i 's:/lib\>:/${baselib}:g' ${S}/tools/llvm-config/llvm-config.cpp
-}
-do_compile_class-native() {
-    ninja -v ${PARALLEL_MAKE} llvm-config llvm-tblgen
-}
-do_install_class-native() {
-    install -D -m 0755 ${B}/bin/llvm-tblgen ${D}${libdir}/llvm-rust/bin/llvm-tblgen
-    install -D -m 0755 ${B}/bin/llvm-config ${D}${libdir}/llvm-rust/bin/llvm-config
-}
-
 do_install_append_class-target() {
     # Disable checks on the native tools, since these should came from the native recipe
     sed -i -e 's/\(.*APPEND.*_IMPORT_CHECK_FILES_FOR_.*{_IMPORT_PREFIX}\/bin\/.*\)/#\1/' ${D}/usr/share/llvm/cmake/LLVMExports-noconfig.cmake

recipes-devtools/rust/rust-llvm/0002-llvm-allow-env-override-of-exe-path.patch

@@ -0,0 +1,70 @@
+From aeccf16eaccdd80e4d5ecaa51673ce4b2bac1130 Mon Sep 17 00:00:00 2001
+From: Martin Kelly <mkelly@xevo.com>
+Date: Fri, 19 May 2017 00:22:57 -0700
+Subject: [PATCH 2/2] llvm: allow env override of exe path
+
+When using a native llvm-config from inside a sysroot, we need llvm-config to
+return the libraries, include directories, etc. from inside the sysroot rather
+than from the native sysroot. Thus provide an env override for calling
+llvm-config from a target sysroot.
+
+To let it work in multilib environment, we need to provide a knob to supply
+multilib dirname as well
+
+Upstream-Status: Inappropriate [OE-Specific]
+
+Signed-off-by: Martin Kelly <mkelly@xevo.com>
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+---
+ tools/llvm-config/llvm-config.cpp | 17 ++++++++++++++++-
+ 1 file changed, 16 insertions(+), 1 deletion(-)
+
+Index: llvm/tools/llvm-config/llvm-config.cpp
+===================================================================
+--- llvm.orig/tools/llvm-config/llvm-config.cpp
++++ llvm/tools/llvm-config/llvm-config.cpp
+@@ -225,6 +225,13 @@ Typical components:\n\
+ 
+ /// \brief Compute the path to the main executable.
+ std::string GetExecutablePath(const char *Argv0) {
++  // Hack for Yocto: we need to override the root path when we are using
++  // llvm-config from within a target sysroot.
++  const char *Sysroot = std::getenv("YOCTO_ALTERNATE_EXE_PATH");
++  if (Sysroot != nullptr) {
++    return Sysroot;
++  }
++
+   // This just needs to be some symbol in the binary; C++ doesn't
+   // allow taking the address of ::main however.
+   void *P = (void *)(intptr_t)GetExecutablePath;
+@@ -306,12 +313,21 @@ int main(int argc, char **argv) {
+   std::string ActivePrefix, ActiveBinDir, ActiveIncludeDir, ActiveLibDir,
+               ActiveCMakeDir;
+   std::string ActiveIncludeOption;
++  // Hack for Yocto: we need to override the multilib path when we are using
++  // llvm-config from within a target sysroot.
++  std::string Multilibdir;
++  if (std::getenv("YOCTO_ALTERNATE_MULTILIB_NAME") != nullptr)
++    Multilibdir = std::getenv("YOCTO_ALTERNATE_MULTILIB_NAME");
++  else
++    Multilibdir = "/lib" LLVM_LIBDIR_SUFFIX;
++
+   if (IsInDevelopmentTree) {
+     ActiveIncludeDir = std::string(LLVM_SRC_ROOT) + "/include";
+     ActivePrefix = CurrentExecPrefix;
+ 
+     // CMake organizes the products differently than a normal prefix style
+     // layout.
++
+     switch (DevelopmentTreeLayout) {
+     case CMakeStyle:
+       ActiveBinDir = ActiveObjRoot + "/bin";
+@@ -336,7 +352,7 @@ int main(int argc, char **argv) {
+     SmallString<256> path(StringRef(LLVM_TOOLS_INSTALL_DIR));
+     sys::fs::make_absolute(ActivePrefix, path);
+     ActiveBinDir = path.str();
+-    ActiveLibDir = ActivePrefix + "/lib" + LLVM_LIBDIR_SUFFIX;
++    ActiveLibDir = ActivePrefix + Multilibdir;
+     ActiveCMakeDir = ActiveLibDir + "/cmake/llvm";
+     ActiveIncludeOption = "-I" + ActiveIncludeDir;
+   }