Why are 4 characters allowed in a char variable? [duplicate]

Question

I have the following code in my program:

char ch='abcd';
printf("%c",ch);

The output is d.

I fail to understand why is a char variable allowed to take in 4 characters in its declaration without giving a compile time error.

Note: More than 4 characters is giving an error.

Answer 1

'abcd' is called a multicharacter constant, and will has an implementation-defined value, here your compiler gives you 'd'.

If you use gcc and compile your code with -Wmultichar or -Wall, gcc will warn you about this.

Answer 2

I fail to understand why is a char variable allowed to take in 4 characters in its declaration without giving a compile time error.

It's not packing 4 characters into one char. The multi-character const 'abcd' is of type int and then the compiler does constant conversion to convert it to char (which overflows in this case).