Fix make jobserver warning.

When running the make file with a number of jobs, the following warning was generated by the make process used to parse the dependency makefile generated by OpenSCAD:

make[1]: warning: jobserver unavailable: using -j1.  Add '+' to parent make rule.

With this change, the variables MAKELEVEL and MAKEFLAGS are removed from the environment before starting the child make process.

2 files changed, 12 insertions, 3 deletions

diff --git a/support/lib/util.py b/support/lib/util.py
index 8b65e58..45ecb89 100644
--- a/support/lib/util.py
+++ b/support/lib/util.py
@@ -15,8 +15,17 @@ def TemporaryDirectory():
 		shutil.rmtree(dir)
 
 
-def command(args):
-	process = subprocess.Popen(args)
+def command(args, remove_env = None):
+	if remove_env is None:
+		env = None
+	else:
+		env = dict(os.environ)
+		
+		for i in remove_env:
+			if i in env:
+				del env[i]
+	
+	process = subprocess.Popen(args, env = env)
 	process.wait()
 	
 	if process.returncode:
diff --git a/support/openscad/__main__.py b/support/openscad/__main__.py
index bc1135d..2042a65 100644
--- a/support/openscad/__main__.py
+++ b/support/openscad/__main__.py
@@ -32,7 +32,7 @@ def main(in_path, out_path, deps_path):
 		
 		# Use make to parse the dependency makefile written by OpenSCAD.
 		util.write_file(temp_mk_path, mk_content.encode())
-		util.command(['make', '-s', '-B', '-f', temp_mk_path, '-f', temp_deps_path])
+		util.command(['make', '-s', '-B', '-f', temp_mk_path, '-f', temp_deps_path], remove_env = ['MAKELEVEL', 'MAKEFLAGS'])
 		
 		# All dependencies as paths relative to the project root.
 		deps = set(map(relpath, util.read_file(temp_files_path).decode().splitlines()))