3 files changed, 58 insertions, 0 deletions
diff --git a/testsuite/gna/ticket11/signalevents.vhdl b/testsuite/gna/ticket11/signalevents.vhdl
new file mode 100644
index 0000000..98161ae
--- /dev/null
+++ b/testsuite/gna/ticket11/signalevents.vhdl
@@ -0,0 +1,20 @@
+entity tb is
+end entity;
+
+architecture arch of tb is
+    signal s: integer := 0;
+begin
+    process is
+    begin
+        wait for 1 us;
+        s <= 1;
+        s <= 2 after 1 us;
+        assert s = 0;
+        wait on s;
+        report "s = " & integer'image(s);
+        assert s = 2 severity failure;
+        assert now = 2 us severity failure;
+        wait;
+    end process;
+
+end architecture;
diff --git a/testsuite/gna/ticket11/testsuite.sh b/testsuite/gna/ticket11/testsuite.sh
new file mode 100755
index 0000000..7226710
--- /dev/null
+++ b/testsuite/gna/ticket11/testsuite.sh
@@ -0,0 +1,10 @@
+#! /bin/sh
+
+. ../../testenv.sh
+
+analyze signalevents.vhdl
+elab_simulate tb
+
+clean
+
+echo "Test successful"
diff --git a/translate/grt/grt-signals.adb b/translate/grt/grt-signals.adb
index d939a97..4443bd9 100644
--- a/translate/grt/grt-signals.adb
+++ b/translate/grt/grt-signals.adb
@@ -675,6 +675,34 @@ package body Grt.Signals is
                   Next := Next.Next;
                end if;
             end loop;
+
+            --  A previous assignment (with a 0 after time) may have put this
+            --  signal on the active chain.  But maybe this previous
+            --  transaction has been removed (due to rejection) and therefore
+            --  this signal won't be active at the next delta.  So remove it
+            --  from the active chain.  This is a little bit costly (because
+            --  the chain is simply linked), but that issue doesn't appear
+            --  frequently.
+            if Sign.Link /= null
+              and then Driver.First_Trans.Next.Time /= Current_Time
+            then
+               if Ghdl_Signal_Active_Chain = Sign then
+                  --  At the head of the chain.
+                  --  FIXME: this is not atomic.
+                  Ghdl_Signal_Active_Chain := Sign.Link;
+               else
+                  --  In the middle of the chain.
+                  declare
+                     Prev : Ghdl_Signal_Ptr := Ghdl_Signal_Active_Chain;
+                  begin
+                     while Prev.Link /= Sign loop
+                        Prev := Prev.Link;
+                     end loop;
+                     Prev.Link := Sign.Link;
+                  end;
+               end if;
+               Sign.Link := null;
+            end if;
          end;
       elsif Reject /= 0 then
          --  LRM93 8.4