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I have been trying to convert multiple large ada compilations from a script based approach to using a gnu make 3.82 makefile and could use some veteran knowledge.

Some background:

• GNAT 4.8.5 on Red Hat Enterprise Linux version 7.9
• Each compilation begins with a source list of ~1000 .ada files
• Different versions use some of the same files, there are only ~7000 unique files out of ~14k total of number of files in each source list
• Each file needs to be prepped, chopped, then compiled - binding and linking are done elsewhere

My approach:

• Recipe 1: For each file, prep the files into src/foo/prepped, then chop into src/foo/chopped
• Recipe 2: Copy each chopped file that was created in recipe 1 into the modules SRC/ folder
• Recipe 3: Compile each chopped file from recipe 2 within SRC/ folder and place in OBJ/ folder

Issues:

• The chopping phase causes issues because the file names are changed, and in some cases more files are created. To get around this, I attempt to wildcard each src/foo/prepped folder for its contents and copy them into the SRC/ folder for compilation. Since this list is unknown until the prep/chop phase, make needs to be invoked a second time to pick up these file names.
• During the compile phase, I blindly run each file in the SRC/ folder to compile using a double colon rule because I am unsure of the files output during the compile phase (.ali or .o)
• If a file has already been prepped/chopped from a previous compile, it will not do double work prepping/chopping, but does not copy the file into SRC/

Questions:

• How can I account for the files that are output with gnatchop without already knowing this in advance?
• During the compile phase, how do I write a rule that can create either a .o or .ali file from a .adb or .ads file?