# HG changeset patch
# User Kyle Lippincott <spectral@google.com>
# Date 1568758165 25200
#      Tue Sep 17 15:09:25 2019 -0700
# Node ID d6227c6c0814cf2c07b87d6019717f5b11ce7b2b
# Parent  460f8bf58020a67b4c2e37449661c1b7ae93a25c
osutil: tolerate Py_GetArgcArgv not being set up properly

Differential Revision: https://phab.mercurial-scm.org/D6866

diff --git a/mercurial/cext/osutil.c b/mercurial/cext/osutil.c
--- a/mercurial/cext/osutil.c
+++ b/mercurial/cext/osutil.c
@@ -798,10 +798,17 @@
 			char *argvend;
 			extern void Py_GetArgcArgv(int *argc, char ***argv);
 			Py_GetArgcArgv(&argc, &argv);
+			/* Py_GetArgcArgv may not do much if a custom python
+			 * launcher is used that doesn't record the information
+			 * it needs. Let's handle this gracefully instead of
+			 * segfaulting. */
+			if (argv != NULL)
+				argvend = argvstart = argv[0];
+			else
+				argvend = argvstart = NULL;
 
 			/* Check the memory we can use. Typically, argv[i] and
 			 * argv[i + 1] are continuous. */
-			argvend = argvstart = argv[0];
 			for (i = 0; i < argc; ++i) {
 				if (argv[i] > argvend || argv[i] < argvstart)
 					break; /* not continuous */