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In some context I may imagine an uint overflow could be a symptom of a bug even if it has a perfectly defined semantic in C. Maybe that tool can be configured to signal uint overflows even if they are perfectly defined in C?Just guessing.

-- Lorenzo

On 05/01/2023 15:05, Roberto Ierusalimschy wrote:
For reference that is this line marked with **:

    |  unsigned int luaS_hash (const char *str, size_t l, unsigned int seed)
    |    unsigned int h = seed ^ cast_uint(l);
    |    for (; l > 0; l--)
**|       h ^= ((h<<5) + (h>>2) + cast_byte(str[l - 1]));
    |    return h;
    |  }

Though not sure which part of that would be causing an add overflow because
h is an unsigned int which I believe should not trigger UB when it

The 'reason' itself states "Unsigned integer overflow", which does not
exist in ISO C...

     Process 626150 stopped
     * thread #1, name = 'ufsrv', stop reason = Unsigned integer overflow

-- Roberto