Pre-build step in makefile

Question

How can I run a script, which must execute before all other makefile commands? And it will be nice (but not mandatory) to the script is not executed if there is nothing to build

Answer 1

Thank you for answers. ndim helped me much, asveikau. The final file is one binary executable, so I can use now something like this:

run-script:
    myscript
$(AXF_FILE): run-script $(OBJ_DIRS) $(OBJ_FILES)
    $(LINK) #......

It will run myscript once. {AXF_FILE} value depends on myscript and I must run it before. And in this case myscript runs always, not only when rebuild is needed. After, The Simplest Answer came to my mind:

all: run-script $(AXF_FILE)

That's all ;) (Of course, any target can be used instead of "all")

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Edit: this method execute script after $(AXF_FILE) is calculated too. So it's possible to get wrong value of AXF_FILE. Now only the first answer by ndim works as I need.