Makefile: Multiple targets, one dependency

I have a script that generates 2 code files (For example, src1.c, src2.c) according to another code file (say origin.h).

I use a makefile to build them.

Now, I want the script to be executed when src1.c OR src2.c is older that origin.h. 开发者_JAVA技巧

What is the best way to do that?

Thanks.

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Make src1.c and src2.c jointly dependent on origin.h:

src1.c src2.c : origin.h
        build-sources