Use is_defined to check for HAVE_* variables set by checks.

Note that conf.define('FOO', 1) will NOT set conf.env['FOO'].


git-svn-id: svn://localhost/ardour2/branches/3.0@10164 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/vamp-plugins/wscript

@@ -46,7 +46,7 @@ def build(bld):
     obj.target       = 'ardourvampplugins'
     obj.uselib       = 'FFTW3F'
     obj.use          = 'libvampplugin libqmdsp'
-    if bld.env['HAVE_AUBIO']:
+    if bld.is_defined('HAVE_AUBIO'):
         obj.source += ' Onset.cpp '
         obj.uselib += ' AUBIO '
     obj.vnum         = LIBARDOURVAMPPLUGINS_LIB_VERSION