Why are C character literals ints instead of chars?

Question

In C++, sizeof(\'a\') == sizeof(char) == 1. This makes intuitive sense, since \'a\' is a character literal, and sizeof(char) == 1 as d

Answer 1

I haven't seen a rationale for it (C char literals being int types), but here's something Stroustrup had to say about it (from Design and Evolution 11.2.1 - Fine-Grain Resolution):

In C, the type of a character literal such as 'a' is int. Surprisingly, giving 'a' type char in C++ doesn't cause any compatibility problems. Except for the pathological example sizeof('a'), every construct that can be expressed in both C and C++ gives the same result.

So for the most part, it should cause no problems.