[rfa/testsuite] Extend signull to work with discriptors

[Michael Elizabeth Chastain]

> We're going to have to live with this - the testsuite needs to include 
> deliberately erroneous programs.

Yeah, I see what you're saying, and I agree.  It's not like the test
program is gratuitously non-conforming.  You need this 'desc' to do what
it's doing in order to test what you're testing.

Can you add one more comment?  Something like:

  /* desc is intentionally initialized to a data object.
     This is needed to test descriptors on arches like ia64.  */

It's the old "move the mailing list discussion into a comment" request.

With a comment like this, this patch is approved.  (And also maybe you
have better wording for the comment than I can think of).

Michael C

> 2004-06-15  Andrew Cagney  <cagney@gnu.org>
> 
> 	* gdb.base/signull.c (bowler): Replace data_pointer with data_read
> 	and data_write cases.  Add code_descriptor case.
> 	(zero, desc): New array and pointer.
> 	(data, code): Change to simple pointers.
> 	* gdb.base/signull.exp: Fix probe pattern matching a function
> 	descriptor SIGSEGV.  Replace data_pointer with data_read and
> 	data_write tests.