Fix possible segfault with strdup (undefined behavior)
Fix possible segfault with strdup (undefined behavior)

am11/libsass,FishingCactus/libsass,saper/libsass,webdev1001/libsass,mtwebster/mint-libsass,mtwebster/mint-libsass,khchanel/libsass,am11/libsass,errorx666/libsass,technoAri/libsass,TBAPI-0KA/NSass,mikebarkas/libsass,TBAPI-0KA/NSass,mikebarkas/libsass,FishingCactus/libsass,TBAPI-0KA/NSass,TBAPI-0KA/NSass,technoAri/libsass,webdev1001/libsass,webdev1001/libsass,TBAPI-0KA/NSass,FishingCactus/libsass,webdev1001/libsass,mtwebster/mint-libsass,TBAPI-0KA/NSass,panicinc/libsass,FishingCactus/libsass,FishingCactus/libsass,technoAri/libsass,panicinc/libsass,saper/libsass,mikebarkas/libsass,mtwebster/mint-libsass,am11/libsass,technoAri/libsass,khchanel/libsass,saper/libsass,khchanel/libsass,khchanel/libsass,mtwebster/mint-libsass,errorx666/libsass,saper/libsass,mikebarkas/libsass,webdev1001/libsass,panicinc/libsass,panicinc/libsass,am11/libsass,am11/libsass,khchanel/libsass,mikebarkas/libsass,technoAri/libsass,errorx666/libsass,panicinc/libsass,saper/libsass,errorx666/libsass