ANSI-C grammar - array declarations like [*] et alii

Question

The ANSI C grammar from -link- give me the following rules for array declarations:

 (1) | direct_declarator \'[\' type_qualifier_list assignment_expression \']\'         


        

Answer 1

My K&R2nd (which covers and includes the ANSI standard) does not seem to say anything about [*] either in the text, or in the standard itself. Nor can I make the official grammar in the standard accept that syntax.

It may be related to K&R c (though I don't seem to recall it), may have been a common extension, or have been a proposal that ultimately didn't make the standard.

I would assume it makes the dimension of the array explicitly unspecified. But I'm just guessing.

---

Hmm...gcc accepts

#include 

void f(int s, int a[*]);

int main(void){
  int a[2] = {0};
  f(2,a);
  return 0;
}

void f(int s, int a[]){
  int i;
  for (i=0; i

in ansi, c89 and c99 mode; issuing no warnings even with -Wall. Note that it did not like the [*] syntax in the function definition. Adding -pedantic made it complain about the [*] syntax in c89 and ansi modes, but it continued to accept in in c99 mode.