On Mar 31, 2025, at 9:54 PM, Julien Villemure-Fréchette via Std-Proposals <std-proposals_at_[hidden]> wrote:
>
> There's one point that is very nasty about promotions IMHO: it is when the promotion changes the signedness of the operand. This is especially bad because it will change the semantics of comparisons. This signedness change behavior is also fragile when compiling to different architectures: a signed char or a short could promote to either signed int or unsigned int depending on the target machine. It would be better if promotions could never change signedness.

Assume char is 8 bit, short is 16 bit, int is 32 bit

signed char i{};
unsigned char u{};

auto z = i + u;

Possibilities:

compile-time error
run-time error
z is signed char
z is unsigned char
z is short
z is unsigned short
z is int
z is unsigned int

What is your recommendation?

Howard