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Re: pointer arithmetic for alignment on short or int boundry


Burak,

Thanks. You saved me from having to find that "do-as-I-mean" compiler switch again.

Andy

Try

a = (char *)((unsigned)(a + 1) & (unsigned)((char*) -2))

You can only add or subtract pointers for pointer arithmetic.

Andy Howell wrote:

I need to calculate an address on a short or int boundry. For some reason this is not working:

char *a;

a = (a + 1) & ((char*) -2));

Gcc 3.3 on Solaris complains:

error: invalid operands of types `char*' and `
   char*' to binary `operator&'

Why shouldn't I be able to mask off the low bit?

Thanks,

Andy







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