From 350e718f3a0ea46239a07b37d63213569133b5d2 Mon Sep 17 00:00:00 2001
From: Yilou Wang <wangyilou123@gmail.com>
Date: Tue, 16 Jun 2026 14:46:57 +0200
Subject: [PATCH] restore the assert type warning

---
 src/V3Assert.cpp                          | 16 ++++++++++++++++
 test_regress/t/t_assert_ctl_arg_unsup.out | 14 ++++++++++++++
 test_regress/t/t_assert_ctl_arg_unsup.py  | 16 ++++++++++++++++
 test_regress/t/t_assert_ctl_arg_unsup.v   | 20 ++++++++++++++++++++
 4 files changed, 66 insertions(+)
 create mode 100644 test_regress/t/t_assert_ctl_arg_unsup.out
 create mode 100644 test_regress/t/t_assert_ctl_arg_unsup.py
 create mode 100644 test_regress/t/t_assert_ctl_arg_unsup.v

diff --git a/src/V3Assert.cpp b/src/V3Assert.cpp
index 32d08a14f..18df21153 100644
--- a/src/V3Assert.cpp
+++ b/src/V3Assert.cpp
@@ -1005,6 +1005,22 @@ class AssertVisitor final : public VNVisitor {
             }
         }
 
+        // When assertion_type is a compile-time constant, reject values that cannot be
+        // filtered at runtime because unique/priority violations use bare assertOn() rather
+        // than a per-type assertOnGet() call (IEEE 1800-2023 Table 20-6).
+        if (nodep->assertTypesp()) {
+            if (const AstConst* const typecp = VN_CAST(nodep->assertTypesp(), Const)) {
+                if (typecp->toUInt()
+                    & (VAssertType::EXPECT | VAssertType::UNIQUE | VAssertType::UNIQUE0
+                       | VAssertType::PRIORITY)) {
+                    nodep->unlinkFrBack();
+                    nodep->v3warn(E_UNSUPPORTED, "Unsupported: assert control assertion_type");
+                    VL_DO_DANGLING(pushDeletep(nodep), nodep);
+                    return;
+                }
+            }
+        }
+
         UINFO(9, "Generating assertctl in module: " << m_modp);
         AstCStmt* const callp = new AstCStmt{fl, "vlSymsp->_vm_contextp__->assertCtl("};
         callp->add(nodep->controlTypep()->unlinkFrBack());
diff --git a/test_regress/t/t_assert_ctl_arg_unsup.out b/test_regress/t/t_assert_ctl_arg_unsup.out
new file mode 100644
index 000000000..da5e1145d
--- /dev/null
+++ b/test_regress/t/t_assert_ctl_arg_unsup.out
@@ -0,0 +1,14 @@
+%Error-UNSUPPORTED: t/t_assert_ctl_arg_unsup.v:15:5: Unsupported: assert control assertion_type
+   15 |     $assertcontrol(OFF, EXPECT);
+      |     ^~~~~~~~~~~~~~
+                    ... For error description see https://verilator.org/warn/UNSUPPORTED?v=latest
+%Error-UNSUPPORTED: t/t_assert_ctl_arg_unsup.v:16:5: Unsupported: assert control assertion_type
+   16 |     $assertcontrol(OFF, UNIQUE);
+      |     ^~~~~~~~~~~~~~
+%Error-UNSUPPORTED: t/t_assert_ctl_arg_unsup.v:17:5: Unsupported: assert control assertion_type
+   17 |     $assertcontrol(OFF, UNIQUE0);
+      |     ^~~~~~~~~~~~~~
+%Error-UNSUPPORTED: t/t_assert_ctl_arg_unsup.v:18:5: Unsupported: assert control assertion_type
+   18 |     $assertcontrol(OFF, PRIORITY);
+      |     ^~~~~~~~~~~~~~
+%Error: Exiting due to
diff --git a/test_regress/t/t_assert_ctl_arg_unsup.py b/test_regress/t/t_assert_ctl_arg_unsup.py
new file mode 100644
index 000000000..3160d0589
--- /dev/null
+++ b/test_regress/t/t_assert_ctl_arg_unsup.py
@@ -0,0 +1,16 @@
+#!/usr/bin/env python3
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of either the GNU Lesser General Public License Version 3
+# or the Perl Artistic License Version 2.0.
+# SPDX-FileCopyrightText: 2024 Wilson Snyder
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+import vltest_bootstrap
+
+test.scenarios('vlt')
+
+test.lint(fails=True, expect_filename=test.golden_filename)
+
+test.passes()
diff --git a/test_regress/t/t_assert_ctl_arg_unsup.v b/test_regress/t/t_assert_ctl_arg_unsup.v
new file mode 100644
index 000000000..b041652f2
--- /dev/null
+++ b/test_regress/t/t_assert_ctl_arg_unsup.v
@@ -0,0 +1,20 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed under the Creative Commons Public Domain
+// SPDX-FileCopyrightText: 2024 Antmicro
+// SPDX-License-Identifier: CC0-1.0
+
+module t;
+  let OFF = 4;
+  let EXPECT = 16;
+  let UNIQUE = 32;
+  let UNIQUE0 = 64;
+  let PRIORITY = 128;
+
+  initial begin
+    $assertcontrol(OFF, EXPECT);
+    $assertcontrol(OFF, UNIQUE);
+    $assertcontrol(OFF, UNIQUE0);
+    $assertcontrol(OFF, PRIORITY);
+  end
+endmodule