diff --git a/rtl/linux/sysosh.inc b/rtl/linux/sysosh.inc
index 43c35c7a76..ee0cf0a820 100644
--- a/rtl/linux/sysosh.inc
+++ b/rtl/linux/sysosh.inc
@@ -19,12 +19,9 @@
 type
   { fd are int in C also for 64bit targets (x86_64) }
   THandle = Longint;
+  
   { pthread_t is defined as an "unsigned long" }
-  {$ifdef CPU64}
-  TThreadID = QWord;
-  {$else}
-  TThreadID = THandle;
-  {$endif}
+  TThreadID = PtrUInt;
 
   { pthread_mutex_t }
   PRTLCriticalSection = ^TRTLCriticalSection;