There does seem to be some type inference going on though "auto a; a= 'hi!';", or maybe it's just defaulting to an int/pointer type? If it is type inference it would have been awful to have the variable declaration at the top but the type declaration strewn through the function.

So it looks as though C switched from default static to default auto? I wonder if the programmers of the time sneered at the waste this added?

C still has it around with the same meaning.

Today, auto in C is still a storage class that denotes stack allocation of a variable. This is related to the other storage classes of register, static, and extern.

In C each variable and function has two attributes, type and storage class