2009-03-23 Ian Lance Taylor <iant@google.com>

	* gold-threads.h (class Initialize_lock): Define.
	* gold-threads.cc (class Initialize_lock_once): Define.
	(initialize_lock_control): New static variable.
	(initialize_lock_pointer): New static variable.
	(initialize_lock_once): New static function.
	(Initialize_lock::Initialize_lock): Define.
	(Initialize_lock::initialize): Define.
	* target-select.h: Include "gold-threads.h".
	(class Target_selector): Add lock_ and initialize_lock_ fields.
	Don't define instantiate_target, just declare it.
	* target-select.cc (Target_selector::Target_selector): Initialize
	new fields.
	(Target_selector::instantiate_target): Define.
	* descriptors.h: Include "gold-threads.h".
	(class Descriptors): Add initialize_lock_ field.
	* descriptors.cc (Descriptors::Descriptors): Initialize new
	field.
	(Descriptors::open): Use initialize_lock_ field
	* errors.h (class Errors): Add initialize_lock_ field.
	* errors.cc (Errors::Errors): Initialize new field.
	(Errors::initialize_lock): Use initialize_lock_ field.
	* powerpc.cc (class Target_selector_powerpc): Remove
	instantiated_target_ field.  In do_recognize call
	instantiate_target rather than do_instantiate_target.  In
	do_instantiate_target just allocate a new target.
	* sparc.cc (class Target_selector_sparc): Likewise.

1 files changed, 8 insertions, 6 deletions

diff --git a/gold/target-select.h b/gold/target-select.h
index b0b1d92..d1cd44f 100644
--- a/gold/target-select.h
+++ b/gold/target-select.h
@@ -25,6 +25,8 @@
 
 #include <vector>
 
+#include "gold-threads.h"
+
 namespace gold
 {
 
@@ -136,12 +138,7 @@ class Target_selector
 
   // Instantiate the target and return it.
   Target*
-  instantiate_target()
-  {
-    if (this->instantiated_target_ == NULL)
-      this->instantiated_target_ = this->do_instantiate_target();
-    return this->instantiated_target_;
-  }
+  instantiate_target();
 
  private:
   // ELF machine code.
@@ -157,6 +154,11 @@ class Target_selector
   // The singleton Target structure--this points to an instance of the
   // real implementation.
   Target* instantiated_target_;
+  // Lock to make sure that we don't instantiate the target more than
+  // once.
+  Lock* lock_;
+  // We only want to initialize the lock_ pointer once.
+  Initialize_lock initialize_lock_;
 };
 
 // Select the target for an ELF file.