cheaderc-preprocessorundef

Loop through headers in C preprocessor

Is there a way to loop through all the included/defined header files and then #undef them all?

If looping is the issue, is there another way to #undef all of them with ease?

Solution

  • GNU cpp provides a -dM directive to do exactly that, you can list all the defines:

    gcc -E -dM -c foo.c

    You can then use a sed script to undef them on command line :)

    gcc -E -c foo.c | sed 's/#define/#undef/'

    or do whatever...

    have fun :)