lib/oe/utils: Return empty string in parallel_make

In cmake.bbclass we set CMAKE_BUILD_PARALLEL_LEVEL using parallel_make
function and if PARALLEL_MAKE is set to empty string then this variable
is exported as "None" causing cmake to fail with:
"'CMAKE_BUILD_PARALLEL_LEVEL' environment variable
invalid number 'None' given."

Signed-off-by: Tomasz Dziendzielski <tomasz.dziendzielski@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/lib/oe/utils.py b/meta/lib/oe/utils.py
index 468c76f30f285977df0b999d0bbc691c6d6faa30..9a2187e36f8156cf96fa3b8ca793e1a81acc0188 100644 (file)
--- a/meta/lib/oe/utils.py
+++ b/meta/lib/oe/utils.py
@@ -193,7 +193,7 @@ def parallel_make(d, makeinst=False):
 
         return int(v)
 
-    return None
+    return ''
 
 def parallel_make_argument(d, fmt, limit=None, makeinst=False):
     """