Help with using _attribute_ ((unused))

[dissectcode]

I am trying to learn how to use the attribute unused so I created a little test program. Can you please tell me what is wrong? I get syntax errors "before attribute" and "before (" (sometimes).

#include <stdio.h>
 
#define UNUSED _attribute_ ((unused))
 
void testUnused(int a UNUSED, int b);
 
int main()
{
  //testUnused(2, 5);  //i tried commenting this out, but still get syntax error
  printf("hello\n");
}
 
void testUnused(int a UNUSED, int b)
{
  printf("%d", b);
}
 

thanks!

[weaknessforcats]

Often a little Google goes a long way.

Read this and then look at your code: http://www.unixwiz.net/techtips/gnu-c-attributes.html.