How much do most C compilers remove constant expressions? [closed]

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At least with macros, C compilers are expected to remove at least most constant math operations. For example, func((4 + 40) * 2) is expected to become func(88) during compilation.

I don't know what happens with something like this:

if (1)
    first();
else
    second();

(which is the same as)

const int mybool = 1;
if (mybool)
    first();
else
    second();

Does this just become first(); on most compilers?

What about:

while(0){
    dostuff();
}

Does this get removed?

If the answer isn't just "They all stay", where is a list of the things C compilers are expected to find and remove (aside from optimization)?



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