message: Fixed singlepass tests on Windows
diff: @@ -23,8 +23,11 @@ backends := $(filter-out ,$(backends))
  RUST_VERSION := $(shell rustc -V)
  ifneq (, $(findstring nightly,$(RUST_VERSION)))
  + # Singlepass doesn't work yet on Windows
  + ifneq ($(OS), Windows_NT)
  backends += singlepass
  endif
  +endif
  ifneq ($(OS), Windows_NT)
  bold := $(shell tput bold)
  