cmake: in SDK use OE env var to set default toolchain

Patch the location in cmake where the toolchain file is loaded
to use the (new) OE_CMAKE_TOOLCHAIN_FILE variable to select a default
toolchain if no toolchain has been specified. The cmake alias is
removed.

The alternatives:

 - shell alias fails when cmake is called indirectly (ex: a makefile
   managing several projects which calls cmake for some of them)
   because aliases are not inherited

 - wrapper script that unconditionally adds "-D..." breaks cmake's
   build tests and many other things as it causes cmake to believe it
   should be configuring things when it should not be. For example,
   `cmake -DCMAKE_TOOLCHAIN_FILE=... --build .` does not work (note
   that this also breaks people directly using `cmake --build .` with
   the current alias).

Signed-off-by: Cody P Schafer <dev@codyps.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/meta/recipes-devtools/cmake/cmake_3.11.4.bb b/meta/recipes-devtools/cmake/cmake_3.11.4.bb
index 3f8fd7a997..eb055b9757 100644
--- a/meta/recipes-devtools/cmake/cmake_3.11.4.bb
+++ b/meta/recipes-devtools/cmake/cmake_3.11.4.bb
@@ -6,7 +6,9 @@ DEPENDS += "curl expat zlib libarchive xz ncurses bzip2"
 
 SRC_URI_append_class-nativesdk = " \
     file://OEToolchainConfig.cmake \
-    file://environment.d-cmake.sh"
+    file://environment.d-cmake.sh \
+    file://0001-CMakeDetermineSystem-use-oe-environment-vars-to-load.patch \
+"
 
 # Strip ${prefix} from ${docdir}, set result into docdir_stripped
 python () {