diff --git a/stage1/spl_ast2ir.c b/stage1/spl_ast2ir.c
index 0a787ee..17663ec 100644
--- a/stage1/spl_ast2ir.c
+++ b/stage1/spl_ast2ir.c
@@ -38,6 +38,56 @@ static spl_ir_node_ref_t ast2ir_intrin_call(spl_ast2ir_t *a, spl_ast_node_t *n,
 static spl_ir_node_ref_t ast2ir_intrin_field(spl_ast2ir_t *a, spl_ast_node_t *n, spl_intrin_t in);
 static spl_ir_node_ref_t ast2ir_intrin_len(spl_ast2ir_t *a, spl_ast_node_t *n);
 
+static spl_ir_node_ref_t emit_zero_value(spl_ast2ir_t *a, spl_type_id_t tid) {
+    spl_type_node_t *tn = spl_type_node(a->sema->type, tid);
+    if (!tn)
+        return 0;
+    switch (tn->kind) {
+    case SPL_TYPE_BOOL:
+        return spl_ir_builder_type_const_bool(a->ir, tid, false);
+    case SPL_TYPE_INT:
+        return spl_ir_builder_type_const_int(a->ir, tid, 0);
+    case SPL_TYPE_FLOAT:
+        return spl_ir_builder_type_const_float(a->ir, tid, 0.0);
+    case SPL_TYPE_PTR:
+    case SPL_TYPE_FN:
+        return spl_ir_builder_type_const_ptr(a->ir, tid, NULL);
+    case SPL_TYPE_ARRAY: {
+        spl_ir_node_ref_t node = spl_ir_builder_agg_construct(a->ir, tid);
+        for (usize i = 0; i < tn->array_type.len; ++i) {
+            spl_ir_node_ref_t f = emit_zero_value(a, tn->array_type.element);
+            if (!f)
+                return 0;
+            spl_ir_builder_agg_construct_field(a->ir, node, f);
+        }
+        return node;
+    }
+    case SPL_TYPE_STRUCT:
+    case SPL_TYPE_SHAPE: {
+        spl_ir_node_ref_t node = spl_ir_builder_agg_construct(a->ir, tid);
+        for (usize i = 0; i < vec_size(tn->agg_type.variants); ++i) {
+            spl_ir_node_ref_t f = emit_zero_value(a, vec_at(tn->agg_type.variants, i).type_id);
+            if (!f)
+                return 0;
+            spl_ir_builder_agg_construct_field(a->ir, node, f);
+        }
+        return node;
+    }
+    case SPL_TYPE_UNION: {
+        spl_ir_node_ref_t node = spl_ir_builder_agg_construct(a->ir, tid);
+        if (vec_size(tn->agg_type.variants) == 0)
+            return node;
+        spl_ir_node_ref_t f = emit_zero_value(a, vec_at(tn->agg_type.variants, 0).type_id);
+        if (!f)
+            return 0;
+        spl_ir_builder_agg_construct_field(a->ir, node, f);
+        return node;
+    }
+    default:
+        return 0;
+    }
+}
+
 static void copy_attrs_to_ir_node(spl_ast2ir_t *a, spl_ast_node_t *n, spl_ir_node_ref_t ir_ref) {
     if (!ir_ref || !n || vec_size(n->attrs) == 0)
         return;
@@ -629,18 +679,24 @@ static spl_ir_node_ref_t emit_expr_raw(spl_ast2ir_t *a, spl_ast_node_ref_t ref)
             vec_at(fields, idx) = f;
         }
 
+        for (usize i = 0; i < nfields; ++i) {
+            if (!vec_at(fields, i)) {
+                spl_type_id_t ftid = vec_at(tn->agg_type.variants, i).type_id;
+                spl_ir_node_ref_t f = emit_zero_value(a, ftid);
+                if (!f)
+                    Panic("cannot zero-init aggregate field #%zu", i);
+                vec_at(fields, i) = f;
+            }
+        }
+
         spl_ir_node_ref_t node = spl_ir_builder_agg_construct(a->ir, t);
         if (!node)
             Panic("agg_construct failed for aggregate literal");
 
-        /* 顺序非常关键：agg_construct_field 是 vec_push，
-           必须严格按字段 index 0..n-1 顺序 push */
         for (usize i = 0; i < nfields; ++i) {
-            spl_ir_node_ref_t f = vec_at(fields, i);
-            if (!f)
-                Panic("aggregate field #%zu missing (sema should have caught this)", i);
-            spl_ir_builder_agg_construct_field(a->ir, node, f);
+            spl_ir_builder_agg_construct_field(a->ir, node, vec_at(fields, i));
         }
+
         vec_free(fields);
         return node;
     }
diff --git a/stage1/spl_ir.c b/stage1/spl_ir.c
index 95f95f7..555e00a 100644
--- a/stage1/spl_ir.c
+++ b/stage1/spl_ir.c
@@ -11,6 +11,8 @@ const char *spl_ir_kind_name(spl_ir_kind_t kind) {
     return "?";
 }
 
+#define SPL_ENUM_TAG_FIELD_IDX 0
+
 void spl_ir_init(spl_ir_t *ir) {
     vec_init(ir->funcs);
     vec_push(ir->funcs, (spl_ir_func_t){0});
diff --git a/stage1/spl_ir2vm.c b/stage1/spl_ir2vm.c
index 4c02854..bd6ed83 100644
--- a/stage1/spl_ir2vm.c
+++ b/stage1/spl_ir2vm.c
@@ -858,8 +858,8 @@ static void cg_node(cgen_t *cg, usize ref, const spl_ir_node_t *n) {
         spl_type_node_t *tn = spl_type_node(cg->ctx->type, n->arith.tid);
         if (tn && tn->kind == SPL_TYPE_BOOL) {
             cg_load_slot(cg, n->arith.left, SPL_BOOL);
-            CG_PUSH(cg, SPL_U8, 0);
-            CG_OP(cg, SPL_EQ, SPL_U8);
+            CG_PUSH(cg, SPL_BOOL, 0);
+            CG_OP(cg, SPL_EQ, SPL_BOOL);
             cg_store_slot(cg, ref, SPL_BOOL);
         } else {
             cg_unop(cg, ref, n, SPL_NOT);
diff --git a/stage1/spl_sema.c b/stage1/spl_sema.c
index dc0d29b..83a5578 100644
--- a/stage1/spl_sema.c
+++ b/stage1/spl_sema.c
@@ -139,7 +139,6 @@ static void sema_resolve_attrs(spl_sema_t *sema, spl_ast_node_ref_vec_t *raw,
     }
 }
 
-static spl_lang_type_id_t sema_parse(spl_sema_t *sema, spl_ast_node_ref_t ref);
 static spl_lang_type_id_t sema_infer(spl_sema_t *sema, spl_ast_node_ref_t ref);
 static spl_lang_type_id_t sema_check(spl_sema_t *sema, spl_ast_node_ref_t ref,
                                      spl_lang_type_id_t expected);
@@ -493,12 +492,12 @@ static spl_lang_type_id_t sema_check(spl_sema_t *sema, spl_ast_node_ref_t ref,
             }
             sema_check(sema, item->struct_init_item.expr, ft);
         }
-        for (usize i = 0; i < nfields; ++i) {
-            if (!seen[i]) {
-                SPL_ERROR(&n->dbg, "missing field `%s`", vec_at(irn->agg_type.variants, i).name);
-                sema->error_count++;
-            }
-        }
+        // for (usize i = 0; i < nfields; ++i) {
+        //     if (!seen[i]) {
+        //         SPL_ERROR(&n->dbg, "missing field `%s`", vec_at(irn->agg_type.variants, i).name);
+        //         sema->error_count++;
+        //     }
+        // }
         free(seen);
         n->resolved_lang_tid = expected;
         n->expected_lang_tid = 0;