I am looking for a way to get the command invoked to compile a specific file inside CMake as a variable. This is the same "command" as it shows up in a compile_commands.json. It is of the form:
%gcc% %bunch of -DSOMETHINGS% %bunch of -Isome/files% -o %cpp files% ... etc.
The project I am in the process of porting to CMake makes a note of the invoked compiler command inside a file, which I am changing to use the configure_file cmake mechanism. The configured file is needed prior to compiling a specific object.
While searching, I found this answer that is pretty much the same question: cmake - get the used commandline flags "-D". However, it is more than 3 years old, and only concerns retrieving a list of the "-D" flags, which the user solved by manually keeping track. I consider this suboptimal. If this command is written into compile_commands.json, I should be able to access this somehow, right? When exactly is compile_commands.json written? Any change I can get this to write that file for like, a non-functional dummy target or something, then access it and use it to configure my file in the real project?
I know this is kind of against the ethos of CMake, and I love the fact that I don't ever have to manually manage the flags myself, however I find it hard to believe there is no way to get them for a specific file, am I overlooking something?
I have looked at CMake properties on source files, and retrieving them using get_property, however I don't believe I can reconstruct the whole command from these.
I am currently generating Unix makefiles, although the mechanism should optimally also work when generating MSVC project files, which I know CMAKE_EXPORT_COMPILE_COMMANDS does not.
Any thoughts and input on this is greatly appreciated!
