diff --git a/stage0/sema.c b/stage0/sema.c
index d0bf8a21e2..a2e6dc585b 100644
--- a/stage0/sema.c
+++ b/stage0/sema.c
@@ -1952,8 +1952,9 @@ static void zirFunc(Sema* sema, SemaBlock* block, uint32_t inst) {
     } else if (ret_ty_body_len == 1) {
         ZirInstRef ret_ty_ref = sema->code.extra[ret_ty_ref_pos];
         // For pre-interned refs, the ZIR ref == IP index.
-        assert(ret_ty_ref < ZIR_REF_START_INDEX);
-        sema->fn_ret_ty = ret_ty_ref;
+        // For inst refs, resolve through inst_map.
+        AirInstRef ret_air = resolveInst(sema, ret_ty_ref);
+        sema->fn_ret_ty = AIR_REF_TO_IP(ret_air);
     } else if (ret_ty_body_len == 2) {
         // Two-instruction return type body: [ptr_type, break_inline].
         uint32_t ret_body_start = ret_ty_ref_pos; // set by both func and func_fancy paths
@@ -1967,8 +1968,8 @@ static void zirFunc(Sema* sema, SemaBlock* block, uint32_t inst) {
             uint32_t pi
                 = sema->code.inst_datas[first_inst].ptr_type.payload_index;
             ZirInstRef elem_ty_ref = sema->code.extra[pi];
-            assert(elem_ty_ref < ZIR_REF_START_INDEX);
-            TypeIndex elem_ty = elem_ty_ref;
+            AirInstRef elem_air = resolveInst(sema, elem_ty_ref);
+            TypeIndex elem_ty = AIR_REF_TO_IP(elem_air);
             uint32_t ip_flags = (uint32_t)zir_size & PTR_FLAGS_SIZE_MASK;
             if (!(zir_flags & 0x02))
                 ip_flags |= PTR_FLAGS_IS_CONST;
@@ -2045,8 +2046,8 @@ static void zirFunc(Sema* sema, SemaBlock* block, uint32_t inst) {
             assert(type_tag == ZIR_INST_BREAK_INLINE);
             ZirInstRef type_ref
                 = sema->code.inst_datas[type_inst].break_data.operand;
-            assert(type_ref < ZIR_REF_START_INDEX); // pre-interned
-            param_ty = type_ref;
+            AirInstRef type_air = resolveInst(sema, type_ref);
+            param_ty = AIR_REF_TO_IP(type_air);
         } else if (type_body_len_p == 2) {
             uint32_t first_inst = sema->code.extra[param_payload + 2];
             ZirInstTag first_tag = sema->code.inst_tags[first_inst];
@@ -2059,8 +2060,8 @@ static void zirFunc(Sema* sema, SemaBlock* block, uint32_t inst) {
                 uint32_t pi
                     = sema->code.inst_datas[first_inst].ptr_type.payload_index;
                 ZirInstRef elem_ty_ref = sema->code.extra[pi]; // PtrType.elem_type
-                assert(elem_ty_ref < ZIR_REF_START_INDEX); // pre-interned
-                TypeIndex elem_ty = elem_ty_ref;
+                AirInstRef elem_air = resolveInst(sema, elem_ty_ref);
+                TypeIndex elem_ty = AIR_REF_TO_IP(elem_air);
                 // Build IP PtrType key.
                 uint32_t ip_flags = (uint32_t)zir_size & PTR_FLAGS_SIZE_MASK;
                 if (!(zir_flags & 0x02)) // ZIR bit 1 = is_mutable; !is_mutable → const