How does GCC look for includes?

[llewelly@dbritsch.dsl.xmission.com]

On Sun, 7 May 2000, Ivan Martinez wrote:

> 	Hello all. Could you tell me how GCC looks for default include files?.
> Does it always look in "/usr/include" or the directories are specified
> in any configuration file?. When it looks in a directory, it doesn't
> necessarily looks in its subdirectories, does it?. Many thanks.
> 

If you add '-v' to your command line, gcc will display the directories
  searched for include files, in the order they are searched in.

For flags that affect where gcc searches for include files, see
  http://gcc.gnu.org/onlinedocs/gcc_2.html#SEC11