FYI: fixlet for linux-dp.exp

[Tom Tromey <tromey@redhat.com>]

I'm checking this in.

While running the test suite I got:

ERROR: tcl error sourcing ../../../archer/gdb/testsuite/gdb.threads/linux-dp.exp.
ERROR: can't array set "seen": variable isn't array
    while executing
"array set seen {}"
    (file "../../../archer/gdb/testsuite/gdb.threads/linux-dp.exp" line 342)
    invoked from within
"source ../../../archer/gdb/testsuite/gdb.threads/linux-dp.exp"
    ("uplevel" body line 1)
    invoked from within
"uplevel #0 source ../../../archer/gdb/testsuite/gdb.threads/linux-dp.exp"
    invoked from within
"catch "uplevel #0 source $test_file_name""


This fixes the problem by unsetting 'seen' before the 'array set'.
There's no reason to do things in the current order, the unset removes
the "array-ness".

It would be nice if dejagnu made a new interpreter for each .exp file,
so that variable name clashes couldn't happen...

Tom

2012-04-25  Tom Tromey  <tromey@redhat.com>

	* gdb.threads/linux-dp.exp: Unset 'seen' before 'array set'.

Index: gdb.threads/linux-dp.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.threads/linux-dp.exp,v
retrieving revision 1.30
diff -u -r1.30 linux-dp.exp
--- gdb.threads/linux-dp.exp	16 Jan 2012 16:21:53 -0000	1.30
+++ gdb.threads/linux-dp.exp	25 Apr 2012 13:50:51 -0000
@@ -339,8 +339,8 @@
 }
 
 set any_interesting 0
+catch {unset seen}
 array set seen {}
-unset seen
 for {set i 1} {$i <= $nthreads} {incr i} {
     if [check_philosopher_stack $i seen] {
 	set any_interesting 1