Hi, I have curious question when reviewing C in terms of integer type comparison.

What happens when

int a;
long int b;
double c;
...

if (a>b) { <----?
.....
} else
if (a<c) { <----?
...
}

I know conversion rules for integer and so on. But I think they only apply for arithmetic operation. I assume > < operator will be different. But can't imagine the details.. maybe sth like
1> variable a hoist to long int to match with b's type
2> compare a and b by substracting (at assembly level cmp)

The underlying question is that will truncation or undefined behavior happen..

Your thoughts are highly appreciated.

the compiler auto converts them to a common type

uaualy it converts the bit width of the small one to the bit width of the large one
like if you have a 16 and 32 bit numbers it will widen the 16 bit number
to 32 so it can compare them