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Fix thread support (at least don't deadlock with oneself)
small fixes for coroutining predicates
force Yap to recover space in arrays of dbrefs
use private predicates in debugger.


git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1084 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

C/sysbits.c

@@ -1048,7 +1048,7 @@ static RETSIGTYPE
 HandleSIGSEGV(int   sig)
 {
   if (Yap_PrologMode & ExtendStackMode) {
-    fprintf(stderr,  "[ FATAL ERROR: OS memory allocation crashed: bailing out ]~n");
+    fprintf(stderr,  "%% YAP FATAL ERROR: OS memory allocation crashed: bailing out~n");
     exit(1);
   }
   SearchForTrailFault();