From bcc7380e82e017e671c784b6cfd3dd095b2fa6bd Mon Sep 17 00:00:00 2001
From: Max Horn <max@quendi.de>
Date: Thu, 26 Apr 2018 13:10:55 +0200
Subject: [PATCH] kernel: fix marking of precords and component objects

---
 src/objects.c |  4 ++--
 src/precord.c | 26 ++++++++++++++++++++++----
 src/precord.h |  4 ++++
 3 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/src/objects.c b/src/objects.c
index c6b4e00bd62..5d52715029b 100644
--- a/src/objects.c
+++ b/src/objects.c
@@ -2009,14 +2009,14 @@ static Int InitKernel (
 
     /* install the marking methods                                         */
     InfoBags[         T_COMOBJ          ].name = "object (component)";
-    InitMarkFuncBags( T_COMOBJ          , MarkAllSubBags  );
+    InitMarkFuncBags( T_COMOBJ          , MarkPRecSubBags );
     InfoBags[         T_POSOBJ          ].name = "object (positional)";
     InitMarkFuncBags( T_POSOBJ          , MarkAllSubBags  );
     InfoBags[         T_DATOBJ          ].name = "object (data)";
     InitMarkFuncBags( T_DATOBJ          , MarkOneSubBags  );
 #if !defined(USE_THREADSAFE_COPYING)
     InfoBags[         T_COMOBJ +COPYING ].name = "object (component,copied)";
-    InitMarkFuncBags( T_COMOBJ +COPYING , MarkAllSubBags  );
+    InitMarkFuncBags( T_COMOBJ +COPYING , MarkPRecSubBags );
     InfoBags[         T_POSOBJ +COPYING ].name = "object (positional,copied)";
     InitMarkFuncBags( T_POSOBJ +COPYING , MarkAllSubBags  );
     InfoBags[         T_DATOBJ +COPYING ].name = "object (data,copied)";
diff --git a/src/precord.c b/src/precord.c
index c10c42ce247..605846a0a67 100644
--- a/src/precord.c
+++ b/src/precord.c
@@ -821,6 +821,24 @@ void LoadPRec( Obj prec )
     }
 }
 
+/****************************************************************************
+**
+*F  MarkPRecSubBags( <bag> ) . . . . marking function for precs and com. objs
+**
+**  'MarkPRecSubBags' is the marking function for bags of type 'T_PREC' or
+**  'T_COMOBJ'.
+*/
+void MarkPRecSubBags(Obj bag)
+{
+    const Bag * data = CONST_PTR_BAG(bag);
+    const UInt count = SIZE_BAG(bag) / sizeof(Bag);
+    MarkBag(data[0]);     // unused for precords; type for component objects
+    for (UInt i = 3; i < count; i += 2) {
+        MarkBag(data[i]);
+    }
+}
+
+
 /****************************************************************************
 **
 *F * * * * * * * * * * * * * initialize module * * * * * * * * * * * * * * *
@@ -864,11 +882,11 @@ static Int InitKernel (
     /* GASMAN marking functions and GASMAN names                           */
     InitBagNamesFromTable( BagNames );
 
-    InitMarkFuncBags( T_PREC                     , MarkAllSubBags );
-    InitMarkFuncBags( T_PREC +IMMUTABLE          , MarkAllSubBags );
+    InitMarkFuncBags( T_PREC                     , MarkPRecSubBags );
+    InitMarkFuncBags( T_PREC +IMMUTABLE          , MarkPRecSubBags );
 #if !defined(USE_THREADSAFE_COPYING)
-    InitMarkFuncBags( T_PREC            +COPYING , MarkAllSubBags );
-    InitMarkFuncBags( T_PREC +IMMUTABLE +COPYING , MarkAllSubBags );
+    InitMarkFuncBags( T_PREC            +COPYING , MarkPRecSubBags );
+    InitMarkFuncBags( T_PREC +IMMUTABLE +COPYING , MarkPRecSubBags );
 #endif
 
     /* Immutable records are public                                        */
diff --git a/src/precord.h b/src/precord.h
index e753f5c376d..f2d23e97695 100644
--- a/src/precord.h
+++ b/src/precord.h
@@ -260,6 +260,10 @@ extern void CopyPRecord(Obj copy, Obj original);
 #endif
 
 
+
+extern void MarkPRecSubBags(Obj bag);
+
+
 /****************************************************************************
 **
 *F * * * * * * * * * * * * * initialize module * * * * * * * * * * * * * * *