3 files changed, 70 insertions, 14 deletions

diff --git a/recipes-devtools/clang/clang/0004-llvm-allow-env-override-of-exe-path.patch b/recipes-devtools/clang/clang/0004-llvm-allow-env-override-of-exe-path.patch
new file mode 100644
index 0000000..739d188
--- /dev/null
+++ b/recipes-devtools/clang/clang/0004-llvm-allow-env-override-of-exe-path.patch
@@ -0,0 +1,36 @@
+From 60eb14f995e0359aef4ef144338d932cbf9c4531 Mon Sep 17 00:00:00 2001
+From: Martin Kelly <mkelly@xevo.com>
+Date: Wed, 15 Mar 2017 10:50:25 -0700
+Subject: [PATCH] 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.
+
+Signed-off-by: Martin Kelly <mkelly@xevo.com>
+---
+ tools/llvm-config/llvm-config.cpp | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/tools/llvm-config/llvm-config.cpp b/tools/llvm-config/llvm-config.cpp
+index 25344e4..26724c1 100644
+--- a/tools/llvm-config/llvm-config.cpp
++++ b/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;
+-- 
+2.1.4
+
diff --git a/recipes-devtools/clang/clang_git.bb b/recipes-devtools/clang/clang_git.bb
index 67b9597..28baa05 100644
--- a/recipes-devtools/clang/clang_git.bb
+++ b/recipes-devtools/clang/clang_git.bb
@@ -22,6 +22,7 @@ SRC_URI += "\
            file://0001-llvm-Remove-CMAKE_CROSSCOMPILING-so-it-can-cross-com.patch \
            file://0002-llvm-Do-not-assume-linux-glibc.patch \
            file://0003-llvm-TargetLibraryInfo-Undefine-libc-functions-if-th.patch \
+           file://0004-llvm-allow-env-override-of-exe-path.patch \
           "
 
 # Clang patches
@@ -96,12 +97,6 @@ DEPENDS_remove_class-nativesdk = "nativesdk-binutils nativesdk-compiler-rt nativ
 DEPENDS_append_class-nativesdk = " clang-native virtual/${TARGET_PREFIX}binutils-crosssdk virtual/${TARGET_PREFIX}gcc-crosssdk virtual/${TARGET_PREFIX}g++-crosssdk"
 DEPENDS_append_class-target = " clang-cross-${TARGET_ARCH} ${@bb.utils.contains('TOOLCHAIN', 'gcc', 'virtual/${TARGET_PREFIX}gcc virtual/${TARGET_PREFIX}g++', '', d)}"
 
-do_configure_prepend() {
-        # 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" ${S}/tools/llvm-config/llvm-config.cpp
-        sed -ri "s#/(bin|include|lib)(/?\")#/\1/${LLVM_DIR}\2#g" ${S}/tools/llvm-config/llvm-config.cpp
-}
-
 do_compile_prepend_class-native () {
         oe_runmake LLVM-tablegen-host
         oe_runmake CLANG-tablegen-host
diff --git a/recipes-devtools/clang/llvm-common/llvm-config b/recipes-devtools/clang/llvm-common/llvm-config
index a9a416d..9fb14cb 100644
--- a/recipes-devtools/clang/llvm-common/llvm-config
+++ b/recipes-devtools/clang/llvm-common/llvm-config
@@ -1,10 +1,35 @@
-#!/bin/sh
-# Wrapper script for real llvm-config. Simply calls
+#!/bin/bash
+#
+# Wrapper script for llvm-config. Supplies the right environment variables
+# for the target and delegates to the native llvm-config for anything else. This
+# is needed because arguments like --ldflags, --cxxflags, etc. are set by the
+# native compile rather than the target compile.
+#
 
-if [ $WANT_LLVM_RELEASE ]; then
-        exec `dirname $0`/${TARGET_PREFIX}llvm-config$WANT_LLVM_RELEASE ${@}
-else
-  echo "The variable WANT_LLVM_RELEASE is not defined and exported"
-        echo "by your build recipe. Go figure."
-  exit 1
+SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"
+NEXT_LLVM_CONFIG="$(which -a llvm-config | sed -n 2p)"
+export YOCTO_ALTERNATE_EXE_PATH="$(readlink -f "$SCRIPT_DIR/../llvm-config")"
+
+if [[ $# == 0 ]]; then
+  exec "$NEXT_LLVM_CONFIG"
 fi
+
+for arg in "$@"; do
+  case "$arg" in
+    --cppflags)
+      echo $TARGET_CPPFLAGS
+      ;;
+    --cflags)
+      echo $TARGET_CFLAGS
+      ;;
+    --cxxflags)
+      echo $TARGET_CXXFLAGS
+      ;;
+    --ldflags)
+      echo $TARGET_LDFLAGS
+      ;;
+    *)
+      echo "$("$NEXT_LLVM_CONFIG" "$arg")"
+      ;;
+  esac
+done