diff --git a/test/wcc/800_append_wide_elem.c b/test/wcc/800_append_wide_elem.c
index 2e432237..d7036e68 100644
--- a/test/wcc/800_append_wide_elem.c
+++ b/test/wcc/800_append_wide_elem.c
@@ -63,6 +63,15 @@
  *   tagged_ident_src     | append of ALREADY-TAGGED locals      | 42
  *                        | (i64 + bool members) — the widener's |
  *                        | already-tagged source path.          |
+ *   struct_eight_appends | 8 struct-lit appends of the getopt   | 15
+ *                        | option shape ({rune,str} = 32B),     |
+ *                        | full-width readback of element 7 —   |
+ *                        | the >6-element OOB regression pin    |
+ *                        | (getopt's deleted helper fed a stale |
+ *                        | hardcoded membsz=24: 8-slot grow was |
+ *                        | 192B while writes strode 32; the     |
+ *                        | builtin derives 32 from the type     |
+ *                        | table, MOVQ $32, SI).                |
  *   struct_call_loudstop | append(xs, f()) struct-from-call is  | BUILD_FAIL
  *                        | the deferred source shape — must     |
  *                        | fail LOUD on both stages (rule-7),   |
@@ -281,6 +290,23 @@ static const struct row rows[] = {
 	  "};\n",
 	  42 },
 
+	{ "struct_eight_appends",
+	  "package main;\n"
+	  "type option = struct { flag: rune, value: str };\n"
+	  "export fn main() i32 = {\n"
+	  "\tlet opts: []option = [];\n"
+	  "\tappend(opts, option { flag = 'a', value = \"v0\" });\n"
+	  "\tappend(opts, option { flag = 'b', value = \"v1\" });\n"
+	  "\tappend(opts, option { flag = 'c', value = \"v2\" });\n"
+	  "\tappend(opts, option { flag = 'd', value = \"v3\" });\n"
+	  "\tappend(opts, option { flag = 'e', value = \"v4\" });\n"
+	  "\tappend(opts, option { flag = 'f', value = \"v5\" });\n"
+	  "\tappend(opts, option { flag = 'g', value = \"v6\" });\n"
+	  "\tappend(opts, option { flag = 'h', value = \"seventh\" });\n"
+	  "\treturn (opts[7].value.len + opts.len): i32;\n"
+	  "};\n",
+	  15 },
+
 	{ "struct_call_loudstop",
 	  "package main;\n"
 	  "type pt = struct { x: i32, y: i32, z: i64 };\n"