[commit/testsuite] Do not build the DejaGNU status wrapper repeatedly

[Daniel Jacobowitz <drow at false dot org>]

While working on other testing issues, I noticed that every GDB test
recompiled the DejaGNU status wrapper (on targets which need it,
including arm-none-eabi and various others).  All the copies are the
same; we really only need one per multilib.  This patch implements
that idea in the straightforward way.

Tested on arm-none-eabi and x86_64-linux.  Checked in.

2009-11-13  Daniel Jacobowitz  <dan@codesourcery.com>

	* lib/gdb.exp (current_target_name): New procedure.
	(gdb_wrapper_target): New variable.
	(gdb_wrapper_init): Set gdb_wrapper_target.
	(default_gdb_init): Check gdb_wrapper_target before rebuilding the
	wrapper.

---
 gdb/testsuite/lib/gdb.exp |   18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

Index: gdb/testsuite/lib/gdb.exp
===================================================================
--- gdb/testsuite/lib/gdb.exp.orig	2009-11-12 12:40:59.000000000 -0800
+++ gdb/testsuite/lib/gdb.exp	2009-11-13 09:33:15.000000000 -0800
@@ -1699,12 +1699,24 @@ proc test_compiler_info { {compiler ""} 
     return [string match $compiler $compiler_info]
 }
 
+proc current_target_name { } {
+    global target_info
+    if [info exists target_info(target,name)] {
+        set answer $target_info(target,name)
+    } else {
+        set answer ""
+    }
+    return $answer
+}
+
 set gdb_wrapper_initialized 0
+set gdb_wrapper_target ""
 
 proc gdb_wrapper_init { args } {
     global gdb_wrapper_initialized;
     global gdb_wrapper_file;
     global gdb_wrapper_flags;
+    global gdb_wrapper_target
 
     if { $gdb_wrapper_initialized == 1 } { return; }
 
@@ -1719,6 +1731,7 @@ proc gdb_wrapper_init { args } {
 	}
     }
     set gdb_wrapper_initialized 1
+    set gdb_wrapper_target [current_target_name]
 }
 
 # Some targets need to always link a special object in.  Save its path here.
@@ -2361,6 +2374,7 @@ proc gdb_continue { function } {
 
 proc default_gdb_init { args } {
     global gdb_wrapper_initialized
+    global gdb_wrapper_target
     global cleanfiles
     
     set cleanfiles {}
@@ -2369,7 +2383,9 @@ proc default_gdb_init { args } {
 
     # Make sure that the wrapper is rebuilt
     # with the appropriate multilib option.
-    set gdb_wrapper_initialized 0
+    if { $gdb_wrapper_target != [current_target_name] } {
+	set gdb_wrapper_initialized 0
+    }
     
     # Unlike most tests, we have a small number of tests that generate
     # a very large amount of output.  We therefore increase the expect

-- 
Daniel Jacobowitz
CodeSourcery