Why are C character literals ints instead of chars?

c++ c char sizeof
Joseph Garvin picture Joseph Garvin · Jan 11, 2009 · Viewed 21.6k times · Source

In C++, sizeof('a') == sizeof(char) == 1. This makes intuitive sense, since 'a' is a character literal, and sizeof(char) == 1 as defined by the standard.

In C however, sizeof('a') == sizeof(int). That is, it appears that C character literals are actually integers. Does anyone know why? I can find plenty of mentions of this C quirk but no explanation for why it exists.

Answer

Malx picture Malx · Jan 12, 2009

discussion on same subject

"More specifically the integral promotions. In K&R C it was virtually (?) impossible to use a character value without it being promoted to int first, so making character constant int in the first place eliminated that step. There were and still are multi character constants such as 'abcd' or however many will fit in an int."

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