CMake generator expression is not being evaluated

Question

Due to the following warning:

CMake Error at test/CMakeLists.txt:29 (get_target_property):
  The LOCATION property may not be read from target \"my_exe\".  Use t         


        

Answer 1

Here is a quick and easy way to print the value of a generator expression:

add_custom_target(print
        ${CMAKE_COMMAND} -E echo $<1:hello> $<0:world>
    )

In this example, if you run cmake . and then make print, you will see "hello" (without the quotation marks) in the output.

However, if you just use message($<1:hello> $<0:world>), you will see "$<1:hello> $<0:world>" as output (again, without the quotation marks).