diff --git a/mps/qa/function/53.c b/mps/qa/function/53.c
new file mode 100644
index 00000000000..9008da0083c
--- /dev/null
+++ b/mps/qa/function/53.c
@@ -0,0 +1,129 @@
+/* TEST_HEADER
+ summary = use AMC with inactive LO pool
+ language = c
+ link = testlib.o awlfmt.o
+END_HEADER
+*/
+
+#include "testlib.h"
+#include "mpscamc.h"
+#include "mpsclo.h"
+#include "awlfmt.h"
+
+void *stackpointer;
+
+static void test(void)
+{
+ mps_space_t space;
+ mps_pool_t poolamc, poollo;
+ mps_thr_t thread;
+ mps_root_t root;
+
+ mps_fmt_t format;
+ mps_ap_t apamc, aplo;
+
+ mycell *a, *b, *c, *d, *e, *f, *g;
+
+ int i;
+ int j;
+
+ RC;
+
+ cdie(mps_space_create(&space), "create space");
+
+ cdie(mps_thread_reg(&thread, space), "register thread");
+
+ cdie(
+  mps_root_create_reg(&root, space, MPS_RANK_AMBIG, 0, thread,
+   mps_stack_scan_ambig, stackpointer, 0),
+  "create root");
+
+ cdie(
+  mps_fmt_create_A(&format, space, &fmtA),
+  "create format");
+
+ cdie(
+  mps_pool_create(&poolamc, space, mps_class_amc(), format),
+  "create pool");
+
+ cdie(
+  mps_pool_create(&poollo, space, mps_class_lo(), format),
+  "create pool");
+
+ cdie(
+  mps_ap_create(&apamc, poolamc, MPS_RANK_EXACT),
+  "create ap");
+
+ cdie(
+  mps_ap_create(&aplo, poollo, MPS_RANK_EXACT),
+  "create ap");
+
+ b = allocone(apamc, 1, 1);
+
+ for (j=1; j<100; j++)
+ {
+  comment("%i of 100.", j);
+  UC;
+  a = allocone(apamc, 5, 1);
+  b = a;
+  c = a;
+  d = a;
+  e = a;
+  f = a;
+  g = a;
+
+  for (i=1; i<5000; i++)
+  {
+  UC;
+   c = allocone(apamc, 20, 1);
+   d = allocone(apamc, 20, 1);
+   if (ranint(8) == 0) e = c;
+   if (ranint(8) == 0) f = c;
+   if (ranint(8) == 0) g = c;
+  UC;
+   setref(b, 0, c);
+  UC;
+   setref(c, 1, d);
+  UC;
+   setref(c, 2, e);
+  UC;
+   setref(c, 3, f);
+  UC;
+   setref(c, 4, g);
+  UC;
+   b = c;
+  }
+ DC;
+ DMC;
+ }
+
+ mps_ap_destroy(apamc);
+ mps_ap_destroy(aplo);
+ comment("Destroyed aps.");
+
+ mps_pool_destroy(poolamc);
+ mps_pool_destroy(poollo);
+ comment("Destroyed pools.");
+
+ mps_fmt_destroy(format);
+ comment("Destroyed format.");
+
+ mps_root_destroy(root);
+ comment("Destroyed root.");
+
+ mps_thread_dereg(thread);
+ comment("Deregistered thread.");
+
+ mps_space_destroy(space);
+ comment("Destroyed space.");
+
+}
+
+int main(void)
+{
+ void *m;
+ stackpointer=&m; /* hack to get stack pointer */
+
+ easy_tramp(test);
+ return 0;
+}
diff --git a/mps/qa/function/67.c b/mps/qa/function/67.c
new file mode 100644
index 00000000000..8d2a7f9a7d5
--- /dev/null
+++ b/mps/qa/function/67.c
@@ -0,0 +1,120 @@
+/* TEST_HEADER
+ summary = test for non-bug with mark-sweep scanning in AWL
+ language = c
+ link = testlib.o exfmt.o
+END_HEADER
+
+ I wrote this test with drj when we were convinced there was
+ a bug in pool scanning because of ScanStateSetSummary setting
+ unfixed to be potentially bigger than the segment summary. But
+ it turned out not to be a problem, 'cos ScanStateSetSummary is
+ called (at least by AWL) _before_ scanning is done.
+
+*/
+
+#include "testlib.h"
+#include "mpscawl.h"
+#include "mpscamc.h"
+#include "exfmt.h"
+
+void *stackpointer;
+
+static void test(void)
+{
+ mps_space_t space;
+ mps_pool_t poolamc, poolawl;
+ mps_thr_t thread;
+ mps_root_t root, root1, root2;
+
+ mps_fmt_t format;
+ mps_ap_t apamc, apawl;
+
+ mycell *a[3];
+
+ int j;
+
+ cdie(mps_space_create(&space), "create space");
+
+ cdie(mps_thread_reg(&thread, space), "register thread");
+
+ cdie(
+  mps_root_create_table(&root, space, MPS_RANK_EXACT, 0, &a[0], 2),
+  "create table root");
+
+ cdie(
+  mps_root_create_table(&root2, space, MPS_RANK_AMBIG, 0, &a[2], 1),
+  "ambig table root");
+
+ cdie(
+  mps_root_create_table(&root1, space, MPS_RANK_AMBIG, 0, &exfmt_root, 1),
+  "create exfmt root");
+
+ cdie(
+  mps_fmt_create_A(&format, space, &fmtA),
+  "create format");
+
+ cdie(
+  mps_pool_create(&poolamc, space, mps_class_amc(), format),
+  "create pool");
+
+ cdie(
+  mps_pool_create(&poolawl, space, mps_class_awl(), format),
+  "create pool");
+
+ cdie(
+  mps_ap_create(&apawl, poolawl, MPS_RANK_EXACT),
+  "create ap");
+
+ cdie(
+  mps_ap_create(&apamc, poolamc, MPS_RANK_EXACT),
+  "create ap");
+
+ a[1] = allocone(apawl, 2, 1);
+ a[0] = allocone(apawl, 2, 1);
+
+ a[2] = allocone(apamc, 2, 1);
+ setref(a[0], 0, a[2]);
+
+ mps_ap_destroy(apawl);
+ comment("Destroyed awl ap");
+
+ for(j=0; j<100; j++) {
+  allocdumb(apamc, 1024*256, 1);
+ }
+
+ mps_ap_destroy(apamc);
+ comment("Destroyed amc ap.");
+
+ mps_root_destroy(root1);
+ mps_root_destroy(root2);
+ comment("Destroyed ambiguous roots.");
+
+ a[1] = a[0];
+ comment("Now to try arena_collect:");
+ mps_arena_collect(space);
+
+ mps_pool_destroy(poolamc);
+ mps_pool_destroy(poolawl);
+ comment("Destroyed pools.");
+
+ mps_fmt_destroy(format);
+ comment("Destroyed format.");
+
+ mps_root_destroy(root);
+ comment("Destroyed exact roots.");
+
+ mps_thread_dereg(thread);
+ comment("Deregistered thread.");
+
+ mps_space_destroy(space);
+ comment("Destroyed space.");
+}
+
+int main(void)
+{
+ void *m;
+ stackpointer=&m; /* hack to get stack pointer */
+
+ easy_tramp(test);
+ return 0;
+}