From 0dacbc3df69fbbb443f1ecaa0ee57c0157d47843 Mon Sep 17 00:00:00 2001
From: Steven Watanabe <steven@providere-consulting.com>
Date: Tue, 20 Feb 2018 11:38:12 -0700
Subject: [PATCH] Make python.require-py safe to use when python is not found
 at all.

---
 src/tools/python.jam | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/tools/python.jam b/src/tools/python.jam
index 0e0770374..273b28a1e 100644
--- a/src/tools/python.jam
+++ b/src/tools/python.jam
@@ -1044,7 +1044,11 @@ local rule configure ( version ? : cmd-or-prefix ? : includes * : libraries ? :
 # required properties.
 rule require-py ( properties * )
 {
-    local py-ext-target = [ $(.project).find python_for_extensions ] ;
+    local py-ext-target = [ $(.project).find python_for_extensions : no-error ] ;
+    if ! $(py-ext-target)
+    {
+        return <build>no ;
+    }
     local property-set = [ property-set.create $(properties) ] ;
     property-set = [ $(property-set).expand ] ;
     local py-ext-alternative = [ $(py-ext-target).select-alternatives $(property-set) ] ;