The top-level SConscript needn't import an environment.
The top-level SConscript needn't import an environment.

sdalton1/thrust,Ricardo666666/thrust,dachziegel/thrust,sarvex/thrust,GrimDerp/thrust,xiongzhanblake/thrust_src,GrimDerp/thrust,zeryx/thrust,sarvex/thrust,raygit/thrust,jaredhoberock/thrust,thvasilo/thrust,zeryx/thrust,thrust/thrust,arnabgho/thrust,arnabgho/thrust,raygit/thrust,xiongzhanblake/thrust_src,Ricardo666666/thrust,xiongzhanblake/thrust,marksantos/thrust,thrust/thrust,dachziegel/thrust,jaredhoberock/thrust,thrust/thrust,zhenglaizhang/thrust,dachziegel/thrust,arnabgho/thrust,Ricardo666666/thrust,xiongzhanblake/thrust_src,thrust/thrust,egaburov/thrust,sdalton1/thrust,mohamed-ali/thrust,mohamed-ali/thrust,GrimDerp/thrust,jaredhoberock/thrust,egaburov/thrust,zhenglaizhang/thrust,jaredhoberock/thrust,thvasilo/thrust,andrewcorrigan/thrust-multi-permutation-iterator,andrewcorrigan/thrust-multi-permutation-iterator,raygit/thrust,jaredhoberock/thrust,egaburov/thrust,marksantos/thrust,mohamed-ali/thrust,xiongzhanblake/thrust,xiongzhanblake/thrust,thrust/thrust,sdalton1/thrust,sarvex/thrust,zhenglaizhang/thrust,andrewcorrigan/thrust-multi-permutation-iterator,zeryx/thrust,thvasilo/thrust,marksantos/thrust