From b95a79c928fc4a6135d91c0c553cb2a63cf15140 Mon Sep 17 00:00:00 2001
From: Steve Dower <steve.dower@microsoft.com>
Date: Wed, 27 Mar 2019 16:28:41 -0700
Subject: [PATCH] bpo-36245: Fix more empty environment variable checks
 (GH-12592)

---
 PCbuild/get_externals.bat | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/PCbuild/get_externals.bat b/PCbuild/get_externals.bat
index cbeb5a19b55..887fdc94117 100644
--- a/PCbuild/get_externals.bat
+++ b/PCbuild/get_externals.bat
@@ -2,8 +2,8 @@
 setlocal
 rem Simple script to fetch source for external libraries
 
-if "%PCBUILD%"=="" (set PCBUILD=%~dp0)
-if "%EXTERNALS_DIR%"=="" (set EXTERNALS_DIR=%PCBUILD%\..\externals)
+if NOT DEFINED PCBUILD (set PCBUILD=%~dp0)
+if NOT DEFINED EXTERNALS_DIR (set EXTERNALS_DIR=%PCBUILD%\..\externals)
 
 set DO_FETCH=true
 set DO_CLEAN=false