Not gnulib specific, but related to our coding style: Does POSIX somewhere guarantee that the in-memory representation of NULL pointers is 0? I know that C89 doesn't make that guarantee, and that some historic systems used non-0 memory values to represent NULL, but I'm hoping that this is not permitted today by some standard.
I believe there is a bunch of places in gnulib which uses memset(P, 0, sizeof(P)) to initialize structures containing pointers, which wouldn't be OK if this is not the case. /Simon
