diff --git a/src/comp/back/upcall.rs b/src/comp/back/upcall.rs
index 2edc027811c..3c39e889afc 100644
--- a/src/comp/back/upcall.rs
+++ b/src/comp/back/upcall.rs
@@ -37,7 +37,6 @@ type upcalls =
      shared_free: ValueRef,
      mark: ValueRef,
      new_str: ValueRef,
-     new_vec: ValueRef,
      vec_append: ValueRef,
      get_type_desc: ValueRef,
      ivec_resize: ValueRef,
@@ -84,9 +83,6 @@ fn declare_upcalls(_tn: type_names, tydesc_type: TypeRef,
           shared_free: dv("shared_free", ~[T_ptr(T_i8())]),
           mark: d("mark", ~[T_ptr(T_i8())], T_int()),
           new_str: d("new_str", ~[T_ptr(T_i8()), T_size_t()], T_ptr(T_str())),
-          new_vec:
-              d("new_vec", ~[T_size_t(), T_ptr(tydesc_type)],
-                T_opaque_vec_ptr()),
           vec_append:
               d("vec_append",
                 ~[T_ptr(tydesc_type), T_ptr(tydesc_type),
diff --git a/src/rt/rust_upcall.cpp b/src/rt/rust_upcall.cpp
index ac99f501f25..19f27f6fe94 100644
--- a/src/rt/rust_upcall.cpp
+++ b/src/rt/rust_upcall.cpp
@@ -222,24 +222,6 @@ upcall_new_str(rust_task *task, char const *s, size_t fill) {
     return make_str(task, s, fill);
 }
 
-extern "C" CDECL rust_vec *
-upcall_new_vec(rust_task *task, size_t fill, type_desc *td) {
-    LOG_UPCALL_ENTRY(task);
-
-    rust_scheduler *sched = task->sched;
-    DLOG(sched, mem, "upcall new_vec(%" PRIdPTR ")", fill);
-    size_t alloc = next_power_of_two(sizeof(rust_vec) + fill);
-    void *mem = task->malloc(alloc, "rust_vec (upcall_new_vec)", td);
-    if (!mem) {
-        task->fail();
-        return NULL;
-    }
-    rust_vec *v = new (mem) rust_vec(alloc, 0, NULL);
-    LOG(task, mem,
-              "upcall new_vec(%" PRIdPTR ") = 0x%" PRIxPTR, fill, v);
-    return v;
-}
-
 static rust_vec *
 vec_grow(rust_task *task,
          rust_vec *v,
diff --git a/src/rt/rustrt.def.in b/src/rt/rustrt.def.in
index ea3be315831..ca0a344aa95 100644
--- a/src/rt/rustrt.def.in
+++ b/src/rt/rustrt.def.in
@@ -99,7 +99,6 @@ upcall_log_type
 upcall_malloc
 upcall_mark
 upcall_new_str
-upcall_new_vec
 upcall_shared_malloc
 upcall_shared_free
 upcall_sleep