Hi, On 2018-05-24 18:13:23 +0100, Andrew Gierth wrote: > In PG11, pq_sendbyte got changed from taking an int parameter to taking > an int8. > > While that seems to work in general, it does mean that there are now > several places in the code that do the equivalent of: > > unsigned char x = 128; > pq_sendbyte(&buf, x); > > which I believe is not well-defined since pq_sendbyte takes an int8, and > conversions of unrepresentable values to _signed_ integer types are > (iirc) implementation-dependent.
It's not implementation defined in postgres' dialect of C - we rely on accurate signed->unsigned conversions in a number of places. But I doin't think we should increase that reliance, so I think you're right we should do something about this. > There are also some cases where pq_sendint16 is being called for an > unsigned value or a value that might exceed 32767. Hm, which case were you thinking of here? The calls usually are exactly the types that the wire protocol expects, no? > Would it be better for these to take unsigned values, or have unsigned > variants? I wonder if we should just take 'int' out of the name. Say, pg_send{8,16,32,64}(unsigned ...). Greetings, Andres Freund