PROJECT(test_unassigned)

# Variable expansion seems to work

SET(foo ${nonexistent})
ADD_EXECUTABLE(bar bar.cc ${nonexistent})

SET(real "Hello There")
STRING(LENGTH ${real} real_len)
MESSAGE(STATUS "length of string is ${real_len} another ${nonexistent} here")

# Test the special keyword

SET(secret $ALLOWUNDEF{possibly_empty_var})

# Test overriding variable

SET(CMAKE_ALLOW_UNKNOWN_VARIABLE_READ_ACCESS 1)
SET(foo ${bar})