Limit number of threads to prevent bombing the system

build/pkgs/numpy/package-version.txt

@@ -1 +1 @@
-1.15.2
+1.15.2.p0

build/pkgs/numpy/patches/cpu_count.patch

@@ -0,0 +1,25 @@
+See https://github.com/numpy/numpy/pull/12088
+
+diff --git a/numpy/distutils/misc_util.py b/numpy/distutils/misc_util.py
+index b30fc27..b07c562 100644
+--- a/numpy/distutils/misc_util.py
++++ b/numpy/distutils/misc_util.py
+@@ -84,7 +84,9 @@ def get_num_build_jobs():
+     Get number of parallel build jobs set by the --parallel command line
+     argument of setup.py
+     If the command did not receive a setting the environment variable
+-    NPY_NUM_BUILD_JOBS checked and if that is unset it returns 1.
++    NPY_NUM_BUILD_JOBS checked. If that is unset, return the number of
++    processors on the system, with a maximum of 8 (to prevent bombing
++    the system if there a lot of CPUs).
+
+     Returns
+     -------
+@@ -97,6 +99,7 @@ def get_num_build_jobs():
+         cpu_count = len(os.sched_getaffinity(0))
+     except AttributeError:
+         cpu_count = multiprocessing.cpu_count()
++    cpu_count = min(cpu_count, 8)
+     envjobs = int(os.environ.get("NPY_NUM_BUILD_JOBS", cpu_count))
+     dist = get_distribution()
+     # may be None during configuration