[OE-core] [PATCH] cmake.bbclass: allow cmake to find hosttools

[Pascal Bach]

Currently the generated toolchain file is unable to find hosttools as they
do not appear in the search paths.

One example where this is useful is for projects that query git for their version
number as git is usually provided via HOSTTOOLS.

Just adding HOSTTOOLS_DIR is not enough as binaries are located directly under
${HOSTTOOLS_DIR}. Like ${HOSTTOOLS_DIR}/git for example.
CMake however only searches in [s]bin sub directories of the paths specified in
CMAKE_FIND_ROOT_PATH. Explicitly adding / to CMAKE_SYSTEM_PROGRAM_PATH makes
CMake look in the right location.

Signed-off-by: Pascal Bach <pascal.bach at siemens.com>
---
 meta/classes/cmake.bbclass | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/meta/classes/cmake.bbclass b/meta/classes/cmake.bbclass
index 684f71299a..421d85fd9d 100644
--- a/meta/classes/cmake.bbclass
+++ b/meta/classes/cmake.bbclass
@@ -92,7 +92,7 @@ set( CMAKE_CXX_LINK_FLAGS "${OECMAKE_CXX_LINK_FLAGS}" CACHE STRING "LDFLAGS" )
 
 # only search in the paths provided so cmake doesnt pick
 # up libraries and tools from the native build machine
-set( CMAKE_FIND_ROOT_PATH ${STAGING_DIR_HOST} ${STAGING_DIR_NATIVE} ${CROSS_DIR} ${OECMAKE_PERLNATIVE_DIR} ${OECMAKE_EXTRA_ROOT_PATH} ${EXTERNAL_TOOLCHAIN})
+set( CMAKE_FIND_ROOT_PATH ${STAGING_DIR_HOST} ${STAGING_DIR_NATIVE} ${CROSS_DIR} ${OECMAKE_PERLNATIVE_DIR} ${OECMAKE_EXTRA_ROOT_PATH} ${EXTERNAL_TOOLCHAIN} ${HOSTTOOLS_DIR})
 set( CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ${OECMAKE_FIND_ROOT_PATH_MODE} )
 set( CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ${OECMAKE_FIND_ROOT_PATH_MODE} )
 set( CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ${OECMAKE_FIND_ROOT_PATH_MODE} )
@@ -113,6 +113,10 @@ list(APPEND CMAKE_MODULE_PATH "${STAGING_DATADIR}/cmake/Modules/")
 # add for non /usr/lib libdir, e.g. /usr/lib64
 set( CMAKE_SYSTEM_LIBRARY_PATH ${libdir} ${base_libdir})
 
+# by default CMake only looks in [s]bin subdirectories of CMAKE_FIND_ROOT_PATH
+# adding / makes CMake look for binaries in hosttools too.
+set( CMAKE_SYSTEM_PROGRAM_PATH /)
+
 # avoid treating imports as system includes
 set( CMAKE_NO_SYSTEM_FROM_IMPORTED ON)
 
-- 
2.11.0