Re: Function call evaluation order

Frederico Pissarra wrote:
"Carl Daniel [VC++ MVP]"
The problem that precedence alone doesn't cover is that the relative
order of evaluation of the arguments of the three function calls is
not defined, nor is whether the evaluation of those arguments
overlaps.

Still... In the last example I show to you, here is the assembly
generated by compiling without optimizations (cl -Od -FAs -Fa -c
test.c) - of course the code sintax is a little more complex than
that... but it shows pos and pre increment in action...

You missed the point entirely - there's no issue here with understanding of
pre- and post-increment.

Code like the example that started this thread:

s.assign(data[i++]).append(data[i++]).append(data[i++]);

has undefined behavior.

Yes, it may do exactly what you hope it does, but it's not required to, and
there are reasonable code generation sequences where it does something
nearly opposite to what you expected.

-cd


.

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