use all cpu cores when building libraries in test runner

1 files changed, 3 insertions, 1 deletions

diff --git a/tools/shared.py b/tools/shared.py
index 3456ab18..cbeb3eda 100644
--- a/tools/shared.py
+++ b/tools/shared.py
@@ -926,7 +926,7 @@ class Building:
 
 
   @staticmethod
-  def build_library(name, build_dir, output_dir, generated_libs, configure=['sh', './configure'], configure_args=[], make=['make'], make_args=['-j', '2'], cache=None, cache_name=None, copy_project=False, env_init={}, source_dir=None, native=False):
+  def build_library(name, build_dir, output_dir, generated_libs, configure=['sh', './configure'], configure_args=[], make=['make'], make_args='help', cache=None, cache_name=None, copy_project=False, env_init={}, source_dir=None, native=False):
     ''' Build a library into a .bc file. We build the .bc file once and cache it for all our tests. (We cache in
         memory since the test directory is destroyed and recreated for each test. Note that we cache separately
         for different compilers).
@@ -934,6 +934,8 @@ class Building:
 
     if type(generated_libs) is not list: generated_libs = [generated_libs]
     if source_dir is None: source_dir = path_from_root('tests', name.replace('_native', ''))
+    if make_args == 'help':
+      make_args = ['-j', str(multiprocessing.cpu_count())]
 
     temp_dir = build_dir
     if copy_project: