scons: check for existance of 'MSVC_VERSION' in env

Evidently, MSVC_VERSION isn't always defined so check for it before
checking the MSVC version.

Suggested by Jose.

diff --git a/scons/gallium.py b/scons/gallium.py
index b28be5d896169ced6f3f64866917c3496d149018..57b5b418f98702c4cdf9433c1604ef00040caf1c 100755 (executable)
--- a/scons/gallium.py
+++ b/scons/gallium.py
@@ -402,7 +402,7 @@ def generate(env):
               '/Oi', # enable intrinsic functions
             ]
         else:
-            if distutils.version.LooseVersion(env['MSVC_VERSION']) < distutils.version.LooseVersion('11.0'):
+            if 'MSVC_VERSION' in env and distutils.version.LooseVersion(env['MSVC_VERSION']) < distutils.version.LooseVersion('11.0'):
                 print 'scons: warning: Visual Studio versions prior to 2012 are known to produce incorrect code when optimizations are enabled ( https://bugs.freedesktop.org/show_bug.cgi?id=58718 )'
             ccflags += [
                 '/O2', # optimize for speed