X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Flibpspp%2Ftaint.c;h=3a74587bb5918ae8cee61766619187b5ca758532;hb=ebbfbe937906e4b4ca577478965cf06d1a812715;hp=0c4194d524bea593d160239f4caffe39bd99497a;hpb=43b1296aafe7582e7dbe6c2b6a8b478d7d9b0fcf;p=pspp-builds.git

diff --git a/src/libpspp/taint.c b/src/libpspp/taint.c
index 0c4194d5..3a74587b 100644
--- a/src/libpspp/taint.c
+++ b/src/libpspp/taint.c
@@ -95,26 +95,31 @@ taint_clone (const struct taint *taint_)
 bool
 taint_destroy (struct taint *taint)
 {
-  bool was_tainted = taint_is_tainted (taint);
-  if (--taint->ref_cnt == 0)
+  if ( taint )
     {
-      size_t i, j;
-
-      for (i = 0; i < taint->predecessors.cnt; i++)
-        for (j = 0; j < taint->successors.cnt; j++)
-          taint_propagate (taint->predecessors.taints[i],
-                           taint->successors.taints[j]);
-
-      for (i = 0; i < taint->predecessors.cnt; i++)
-        taint_list_remove (&taint->predecessors.taints[i]->successors, taint);
-      for (i = 0; i < taint->successors.cnt; i++)
-        taint_list_remove (&taint->successors.taints[i]->predecessors, taint);
-
-      taint_list_destroy (&taint->successors);
-      taint_list_destroy (&taint->predecessors);
-      free (taint);
+      bool was_tainted = taint_is_tainted (taint);
+      if (--taint->ref_cnt == 0)
+	{
+	  size_t i, j;
+
+	  for (i = 0; i < taint->predecessors.cnt; i++)
+	    for (j = 0; j < taint->successors.cnt; j++)
+	      taint_propagate (taint->predecessors.taints[i],
+			       taint->successors.taints[j]);
+
+	  for (i = 0; i < taint->predecessors.cnt; i++)
+	    taint_list_remove (&taint->predecessors.taints[i]->successors, taint);
+	  for (i = 0; i < taint->successors.cnt; i++)
+	    taint_list_remove (&taint->successors.taints[i]->predecessors, taint);
+
+	  taint_list_destroy (&taint->successors);
+	  taint_list_destroy (&taint->predecessors);
+	  free (taint);
+	}
+      return !was_tainted;
     }
-  return !was_tainted;
+
+  return true;
 }
 
 /* Adds a propagation relationship from FROM to TO.  This means