diff --git a/mk/rt.mk b/mk/rt.mk
index 1d6634557d0..ac4ebb842cb 100644
--- a/mk/rt.mk
+++ b/mk/rt.mk
@@ -67,7 +67,6 @@ RUNTIME_CS_$(1) := \
 
 RUNTIME_S_$(1) := rt/arch/$$(HOST_$(1))/_context.S \
                   rt/arch/$$(HOST_$(1))/ccall.S \
-                  rt/arch/$$(HOST_$(1))/morestack.S \
                   rt/arch/$$(HOST_$(1))/record_sp.S
 
 RUNTIME_HDR_$(1) := rt/globals.h \
diff --git a/src/rt/rustrt.def.in b/src/rt/rustrt.def.in
index c0a9a92ba1b..8d78ba16e9c 100644
--- a/src/rt/rustrt.def.in
+++ b/src/rt/rustrt.def.in
@@ -1,4 +1,3 @@
-__morestack
 chan_id_send
 check_claims
 debug_box