bpo-32146: Add documentation about frozen executables on Unix (GH-5850)
diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst
index 1d0920a..a778159 100644
--- a/Doc/library/multiprocessing.rst
+++ b/Doc/library/multiprocessing.rst
@@ -186,6 +186,13 @@
use :func:`get_context` to avoid interfering with the choice of the
library user.
+.. warning::
+
+ The ``'spawn'`` and ``'forkserver'`` start methods cannot currently
+ be used with "frozen" executables (i.e., binaries produced by
+ packages like **PyInstaller** and **cx_Freeze**) on Unix.
+ The ``'fork'`` start method does work.
+
Exchanging objects between processes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~