diff --git a/tccgen.c b/tccgen.c
index 2f5214ec..6566ee4f 100644
--- a/tccgen.c
+++ b/tccgen.c
@@ -4533,6 +4533,8 @@ static int parse_btype(CType *type, AttributeDef *ad, int ignore_label)
         case TOK_BOOL:
             u = VT_BOOL;
             goto basic_type;
+        case TOK_COMPLEX:
+            tcc_error("_Complex is not yet supported");
         case TOK_FLOAT:
             u = VT_FLOAT;
             goto basic_type;
diff --git a/tcctok.h b/tcctok.h
index 52a6e0cc..563984a3 100644
--- a/tcctok.h
+++ b/tcctok.h
@@ -45,6 +45,7 @@
      DEF(TOK_FLOAT, "float")
      DEF(TOK_DOUBLE, "double")
      DEF(TOK_BOOL, "_Bool")
+     DEF(TOK_COMPLEX, "_Complex")
      DEF(TOK_SHORT, "short")
      DEF(TOK_STRUCT, "struct")
      DEF(TOK_UNION, "union")