diff --git a/test/test_acceptance.ml b/test/test_acceptance.ml
index 4271d21..5d5ae0c 100644
--- a/test/test_acceptance.ml
+++ b/test/test_acceptance.ml
@@ -1157,6 +1157,77 @@ ERR@7 unexpected token: not the kind the caller was reading
       print_endline "FAIL  the transfer channel appeared as a local variable"
     end;
 
+    (* LLVM's own verifier, over both entry points. String needles cannot see
+       a DISubprogram the compile unit does not reach, or a call without a
+       !dbg inside a function that has debug info — and that second one is a
+       hard rejection, not a warning, so it would turn every debug build into
+       a clang error rather than into anything visible here.
+
+       [redefinition] is the half that needs this most. It is only ever run at
+       the default debug:false today, and it differs from [program] in exactly
+       the places metadata goes wrong: hidden bodies, the by-name cell and
+       global loads, and flan_reload_install and flan_reload_call, which are
+       raw defines with no subprogram that nonetheless contain calls. *)
+    if Sys.command "command -v opt > /dev/null 2>&1" = 0 then begin
+      let verifies name ir =
+        let f = Filename.concat scratch "flan-dwarf-verify.ll" in
+        Out_channel.with_open_bin f (fun ch -> Out_channel.output_string ch ir);
+        let log = Filename.concat scratch "flan-dwarf-verify.log" in
+        let code =
+          Sys.command
+            (Printf.sprintf "opt -passes=verify -disable-output %s > %s 2>&1"
+               (Filename.quote f) (Filename.quote log))
+        in
+        if code <> 0 then begin
+          incr failures;
+          Printf.printf "FAIL  %s: LLVM's verifier rejected the module\n%s\n" name
+            (In_channel.with_open_bin log In_channel.input_all)
+        end;
+        (try Sys.remove f with Sys_error _ -> ());
+        (try Sys.remove log with Sys_error _ -> ())
+      in
+      (* A program with a bit of everything that emits a call the backend
+         invents rather than one a Tast node asked for: a bounds check, a
+         condition signalled and handled, a restart transferred to, a defer on
+         the way out. Each would be a verifier rejection without a location. *)
+      let src =
+        "(defstruct Missing [id i32])\n\
+         (defvar seen i64)\n\
+         (defvar arr [4 i32])\n\
+         (defn pick [xs [i32]  i i32] i32 (at xs i))\n\
+         (defn fetch [n i32] i32\n\
+        \  (restart-case\n\
+        \    (do (error (Missing {:id n})) 0)\n\
+        \    (use-placeholder [] -1)))\n\
+         (defn run [] i32\n\
+        \  (defer (set seen (+ seen 1)))\n\
+        \  (handler-bind [(Missing [m] (invoke-restart 'use-placeholder))]\n\
+        \    (fetch 3)))\n\
+         (defn main [] i32\n\
+        \  (set (at arr 2) 9)\n\
+        \  (let [s (slice arr 0 4)]\n\
+        \    (print-i64 (i64 (pick s 2))) (newline)\n\
+        \    (print-i64 (i64 (run))) (newline)\n\
+        \    0))\n"
+      in
+      let decls = Parse.program (Reader.read_all ~file:"<verify>" src) in
+      let p = Check.program decls in
+      verifies "the whole program, with debug info"
+        (Emit.program ~debug:true ~pnames:(pnames_of decls) p);
+      (* And a redefinition module against a host that has every name — the
+         shape C-c C-c produces. *)
+      verifies "a redefinition module, with debug info"
+        (Emit.redefinition ~dev:true ~debug:true ~known:(fun _ -> true) p
+           ~fns:[ "fetch"; "run" ]);
+      (* And one against a host that has none of them, which is the other
+         path: every call goes through flan_dev_cell and every global through
+         flan_dev_global, so the module is almost entirely different code. *)
+      verifies "a redefinition of names the host does not have"
+        (Emit.redefinition ~dev:true ~debug:true ~known:(fun _ -> false) p
+           ~fns:[ "fetch"; "run" ])
+    end
+    else print_endline "acceptance: the DWARF verifier cases skipped (no opt)";
+
     (* A debug build and a release build must still be the same program. *)
     let debug_compile ?(dev = false) path =
       let exe =