From 9d5ea703bb1e31c9113556efe396f09edd3b0e97 Mon Sep 17 00:00:00 2001
From: stevenknight <stevenknight@fdb21ef1-2011-0410-befe-b5e4ea1792b1>
Date: Thu, 1 Jan 2009 18:36:08 +0000
Subject: [PATCH] Have the {Append,Prepend}ENVPath() canonicalization make sure
 there's the string is non-null before checking whether the first character is
 '#'.

git-svn-id: http://scons.tigris.org/svn/scons/trunk@3868 fdb21ef1-2011-0410-befe-b5e4ea1792b1
---
 src/CHANGES.txt                 | 5 +++++
 src/engine/SCons/Environment.py | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index d5e1bf9f..c525a843 100644
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -25,6 +25,11 @@ RELEASE 1.X - XXX
 
     - Document TestCommon.shobj_prefix variable.
 
+  From Gary Oberbrunner:
+
+    - Allow AppendENVPath() and PrependENVPath() to interpret '#'
+      for paths relative to the top-level SConstruct directory.
+
   From Greg Spencer:
 
     - Support implicit dependency scanning of files encoded in utf-8
diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index c2a7c76a..338ed37f 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -1203,7 +1203,7 @@ class Base(SubstitutionEnvironment):
     def _canonicalize(self, path):
         if not SCons.Util.is_String(path): # typically a Dir
             path = str(path)
-        if path[0] == '#':
+        if path and path[0] == '#':
             path = str(self.fs.Dir(path))
         return path
 
-- 
2.26.2