SUMMARY: Strange error in C compiler

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        The results of the discussion can be summarized as follows:

        1) There is the only (almost?) portable way to test the
        value of address constants - to use additional variable:

        extern _DYNAMIC[];

        /* global - to avoid optimizations, though gcc I use doesn't
         * optimize "if" when pDYNAMIC is local
         */

        int * pDYNAMIC = _DYNAMIC;
        ...
        {
                if (pDYNAMIC) ....
                else ....
        }

        I must note the error in some answers. Their authors
        propose to test *_DYNAMIC. Obviously, this may cause NULL
        pointer access and therefore coredump.

        2) The source of strange behavior of the C compiler is
        its origin. GCC tries to optimize the "if" always,
        MS-DOS' Microsoft and Borland C don't make any presumptions about
        the value of address constants, and only PCC-derived
        compilers (3 of them have been tested, including SunOS')
        behave strangely.

        Thanks,

-- 
	Leonid A. Broukhis

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