c syntax: array

Question

For char[size], is it true that size must be constant?

Or say,will it work ?

int length;
...

char[length] arr;

Sorry,don't have the environment here so can't try it myself.

Answer 1

Pre C99, yes; the size of an array must be a constant integral expression. C99, however, adds Variable Length Arrays (VLA's), which allow an array to have a dynamic size.