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Dodging undefined behaviour in printf

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Dear c.l.c.

I'm trying to refine my knowledge on the topic of type promotions, and 
now I know how promotion is implied when passing arguments to a function 
whose prototype is missing argument definition, or to functions having 
variadic argument list.

So I was wondering about the following:

	unsigned short x = value;
	printf("%x", x);

Assuming that sizeof(unsigned short) < sizeof(int), I would guess that x 
is promoted to signed int, which is however the wrong type, as it should 
be unsigned int.

Well, it is is also true that the `int` value is not going to be 
negative for sure.

Would this be a problem? Am I supposed to explicitly cast x to (unsigned 
int) when passing it to printf?

I find it interesting that the problem is not a problem on architectures 
where sizeof(unsigned short) == sizeof(unsigned int) -- if I will ever 
find such a thing.

How about %hx then?

-- 
High Crew

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Dodging undefined behaviour in printf highcrew <high.crew3868@fastmail.com> - 2026-09-27 18:12 +0200
  Re: Dodging undefined behaviour in printf Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-09-28 01:47 +0800
  Re: Dodging undefined behaviour in printf Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-09-27 10:48 -0700
  Re: Dodging undefined behaviour in printf James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-09-27 20:30 -0400
  Re: Dodging undefined behaviour in printf David Brown <david.brown@hesbynett.no> - 2026-09-28 09:50 +0200
  Re: Dodging undefined behaviour in printf "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-09-30 13:05 -0700

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