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Re: Ada front-end depends on signed overflow

Better use a union for the (final) conversion, i.e

int conv(unsigned char *c)
{
    unsigned int i;
    union {
        unsigned int u;
        int i;
    } u;

    u.u = 0;
    for (i = 0; i < sizeof u; i++)
      u.u = (u.u << 8) + c[i];

    return u.i;
}


This is not portable, though; accessing a union member other than
the member last stored into is unspecified behaviour (see J.1 and
6.2.6.1).

This is allowed (and defined behaviour) as a GCC extension, though.


Segher

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