What's the reason that C didn't define the order of this?
The horrible undefined behavior of signed integer overflow at least can be explained by the fact that multiple CPU architectures handling those differently existed (though the fact that C even 'attracts' its ill-defined signed integers when you're using unsigned ones by returning a signed int when left shifting an uint16_t by an uint16_t for example is not as forgivable imho)
But this here is something that could be completely defined at the language level, there's nothing CPU dependent here, they could have simply stated in the language specification that e.g. the order of execution of statements is from left to right (and/or other rules like post increment happens after the full statement is finished for example, my point is not whether the rule I type here is complete enough or not but that the language designers could have made it completely defined).
The horrible undefined behavior of signed integer overflow at least can be explained by the fact that multiple CPU architectures handling those differently existed (though the fact that C even 'attracts' its ill-defined signed integers when you're using unsigned ones by returning a signed int when left shifting an uint16_t by an uint16_t for example is not as forgivable imho)
But this here is something that could be completely defined at the language level, there's nothing CPU dependent here, they could have simply stated in the language specification that e.g. the order of execution of statements is from left to right (and/or other rules like post increment happens after the full statement is finished for example, my point is not whether the rule I type here is complete enough or not but that the language designers could have made it completely defined).