Genex: TARGET_PROPERTY disallows non-alphanumeric characters
Currently any value can be set as a property name, however, this seems to break down if a $<TARGET_PROPERTY:...> generator expression is used. Therefore if there are any properties that might contain anything outside of [A-Za-z0-9_], then CMake will error and the project cannot generate. This is an issue when dealing with properties in non-english languages and is also surprising given that CMake's documentation states that it is 8-bit clean. This also makes it harder to generate useful data post-configure without having to resort to using the variable_watch scope hack
This was also surprising given that $<INSTALL_INTERFACE> and $<BUILD_INTERFACE> do support any byte sequence.