diff --git a/sim/common/ChangeLog b/sim/common/ChangeLog
index 418fa10998..a046a96631 100644
--- a/sim/common/ChangeLog
+++ b/sim/common/ChangeLog
@@ -1,3 +1,10 @@
+2004-12-08  Hans-Peter Nilsson  <hp@axis.com>
+
+	* aclocal.m4 (SIM_AC_OUTPUT): Substitute @cgen_breaks@ for "break
+	cgen_rtx_error" in a CGEN-generated simulator.
+	* gdbinit.in: Break on sim_core_signal too.  Have autoconf
+	replacement for CGEN-related breakpoints.
+
 2004-12-07  Hans-Peter Nilsson  <hp@axis.com>
 
 	* Make-common.in (sim-basics_h): Add $(callback_h).
diff --git a/sim/common/aclocal.m4 b/sim/common/aclocal.m4
index 20c72ffe15..578658ccaf 100644
--- a/sim/common/aclocal.m4
+++ b/sim/common/aclocal.m4
@@ -861,6 +861,12 @@ dnl the target's fragment at the appropriate points.
 AC_DEFUN(SIM_AC_OUTPUT,
 [
 AC_LINK_FILES($sim_link_files, $sim_link_links)
+dnl Make @cgen_breaks@ non-null only if the sim uses CGEN.
+cgen_breaks=""
+if grep CGEN_MAINT $srcdir/Makefile.in >/dev/null; then
+cgen_breaks="break cgen_rtx_error";
+fi
+AC_SUBST(cgen_breaks)
 AC_OUTPUT(Makefile.sim:Makefile.in Make-common.sim:../common/Make-common.in .gdbinit:../common/gdbinit.in,
 [case "x$CONFIG_FILES" in
  xMakefile*)
diff --git a/sim/common/gdbinit.in b/sim/common/gdbinit.in
index ddda344a2e..ab9d7b3d54 100644
--- a/sim/common/gdbinit.in
+++ b/sim/common/gdbinit.in
@@ -1,4 +1,6 @@
 break sim_io_error
+break sim_core_signal
+@cgen_breaks@
 
 define dump
 set sim_debug_dump ()