"gallium/targets: scons: wire swr support for libgl-gdi/libgl-xlib/osmesa" ... or alike ? > +import SCons.Script.SConscript > + > + if 'swr' in SCons.Script.ARGUMENTS and SCons.Script.ARGUMENTS['swr']: With the "move this to top level" suggestion this will read roughly as if env['swr']: -Emil