diff --git a/Misc/NEWS.d/next/Build/2019-03-18-23-49-15.bpo-36356.WNrwYI.rst b/Misc/NEWS.d/next/Build/2019-03-18-23-49-15.bpo-36356.WNrwYI.rst
new file mode 100644
index 000000000000000..d30f5d586b7c149
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2019-03-18-23-49-15.bpo-36356.WNrwYI.rst
@@ -0,0 +1 @@
+Fix leaks that led to build failure when configured with address sanitizer.
diff --git a/Python/preconfig.c b/Python/preconfig.c
index 1efc7ee5c56ed1a..b03436181c860bd 100644
--- a/Python/preconfig.c
+++ b/Python/preconfig.c
@@ -514,6 +514,7 @@ _PyPreConfig_Read(_PyPreConfig *config)
     err = preconfig_read(config, NULL);
 
     setlocale(LC_CTYPE, old_loc);
+    PyMem_RawFree(old_loc);
 
     return err;
 }