diff --git a/libs/pbd/debug.cc b/libs/pbd/debug.cc
index d1210b3dff..2fcbc1f510 100644
--- a/libs/pbd/debug.cc
+++ b/libs/pbd/debug.cc
@@ -61,6 +61,7 @@ DebugBits PBD::DEBUG::Configuration = PBD::new_debug_bit ("configuration");
 DebugBits PBD::DEBUG::UndoHistory = PBD::new_debug_bit ("undohistory");
 DebugBits PBD::DEBUG::Timing = PBD::new_debug_bit ("timing");
 DebugBits PBD::DEBUG::Threads = PBD::new_debug_bit ("threads");
+DebugBits PBD::DEBUG::ThreadName = PBD::new_debug_bit ("threadname");
 DebugBits PBD::DEBUG::Locale = PBD::new_debug_bit ("locale");
 DebugBits PBD::DEBUG::StringConvert = PBD::new_debug_bit ("stringconvert");
 DebugBits PBD::DEBUG::DebugTimestamps = PBD::new_debug_bit ("debugtimestamps");
@@ -103,7 +104,7 @@ PBD::new_debug_bit (const char* name)
 void
 PBD::debug_only_print (const char* prefix, string str)
 {
-	if ((PBD::debug_bits & DEBUG::Threads).any()) {
+	if ((PBD::debug_bits & DEBUG::ThreadName).any()) {
 		printf ("0x%lx (%s) ", (intptr_t) DEBUG_THREAD_SELF, pthread_name());
 	}
 
diff --git a/libs/pbd/pbd/debug.h b/libs/pbd/pbd/debug.h
index fdd7f6d503..c00be2d811 100644
--- a/libs/pbd/pbd/debug.h
+++ b/libs/pbd/pbd/debug.h
@@ -39,7 +39,7 @@
 
 namespace PBD {
 
-	typedef std::bitset<128> DebugBits;
+	typedef std::bitset<192> DebugBits;
 
 	LIBPBD_API extern DebugBits debug_bits;
 	LIBPBD_API DebugBits new_debug_bit (const char* name);
@@ -64,6 +64,7 @@ namespace PBD {
 		LIBPBD_API extern DebugBits UndoHistory;
 		LIBPBD_API extern DebugBits Timing;
 		LIBPBD_API extern DebugBits Threads;
+		LIBPBD_API extern DebugBits ThreadName;
 		LIBPBD_API extern DebugBits Locale;
 		LIBPBD_API extern DebugBits StringConvert;
 		LIBPBD_API extern DebugBits DebugTimestamps;