lang/icon has this in src/runtime/fmonitr.r, which doesn't work any more
because profil(2) changed.

    281 #if UNIX
    282    /*
    283     * Call profil(2) to enable program counter profiling.  We use the smallest
    284     *  allowable scale factor in order to minimize the number of counters;
    285     *  we assume that the text of iconx does not exceed 256K and so we use
    286     *  four bins.  One of these four bins will be incremented every system
    287     *  clock tick (typically 4 to 20 ms).
    288     *
    289     *  Take your local profil(2) man page with a grain of salt.  All the systems
    290     *  we tested really maintain 16-bit counters despite what the man pages say.
    291     *  Some also say that a scale factor of two maps everything to one counter;
    292     *  that is believed to be a no-longer-correct statement dating from the days
    293     *  when the maximum program size was 64K.
    294     *
    295     *  The reference to EVInit below just obtains an arbitrary address within
    296     *  the text segment.
    297     */
    298 #ifdef HaveProfil
    299    profil(ticker.s, sizeof(ticker.s), (int) EVInit & ~0x3FFFF, 2);
    300 #endif                                  /* HaveProfil*/
    301 #endif                                  /* UNIX */

Should I just add a !__OpenBSD__ check, or would you like to do
something else?