From c2c00888d619a00f9057e3eb35249974f6396600 Mon Sep 17 00:00:00 2001
From: Wilson Snyder <wsnyder@wsnyder.org>
Date: Thu, 18 Dec 2025 20:45:22 -0500
Subject: [PATCH] Fix firing array selects of events (#6829).

---
 Changes                              |  1 +
 src/V3Width.cpp                      |  4 ++
 test_regress/t/t_event_array_fire.py | 18 ++++++++
 test_regress/t/t_event_array_fire.v  | 65 ++++++++++++++++++++++++++++
 4 files changed, 88 insertions(+)
 create mode 100755 test_regress/t/t_event_array_fire.py
 create mode 100644 test_regress/t/t_event_array_fire.v

diff --git a/Changes b/Changes
index af3e6403b..4ae4b59fa 100644
--- a/Changes
+++ b/Changes
@@ -110,6 +110,7 @@ Verilator 5.043 devel
 * Fix O(n*2) analysis in const-bit-op-tree (#6791). [Geza Lore]
 * Fix nested struct within parameter port list (#6818) (#6824). [Luca Colagrande]
 * Fix duplicate name error with interface initial blocks (#6804) (#6805). [Thomas Dybdahl Ahle]
+* Fix firing array selects of events (#6829). [Amal Araweelo Almis]
 
 
 Verilator 5.042 2025-11-02
diff --git a/src/V3Width.cpp b/src/V3Width.cpp
index f4e7809de..ec931747f 100644
--- a/src/V3Width.cpp
+++ b/src/V3Width.cpp
@@ -741,6 +741,10 @@ class WidthVisitor final : public VNVisitor {
         if (nodep->stmtsp()) nodep->addNextHere(nodep->stmtsp()->unlinkFrBackWithNext());
         VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
     }
+    void visit(AstFireEvent* nodep) override {
+        assertAtStatement(nodep);
+        iterateCheckSelf(nodep, "LHS", nodep->operandp(), SELF, BOTH);
+    }
     void visit(AstFork* nodep) override {
         if (!m_underFork && VN_IS(m_ftaskp, Func) && !nodep->joinType().joinNone()) {
             nodep->v3error("Only fork .. join_none is legal in functions. "
diff --git a/test_regress/t/t_event_array_fire.py b/test_regress/t/t_event_array_fire.py
new file mode 100755
index 000000000..bd059b0f2
--- /dev/null
+++ b/test_regress/t/t_event_array_fire.py
@@ -0,0 +1,18 @@
+#!/usr/bin/env python3
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2025 by Wilson Snyder. 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-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+import vltest_bootstrap
+
+test.scenarios('simulator')
+
+test.compile(verilator_flags2=['--binary'])
+
+test.execute()
+
+test.passes()
diff --git a/test_regress/t/t_event_array_fire.v b/test_regress/t/t_event_array_fire.v
new file mode 100644
index 000000000..09e2eedec
--- /dev/null
+++ b/test_regress/t/t_event_array_fire.v
@@ -0,0 +1,65 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed under the Creative Commons Public Domain, for
+// any use, without warranty, 2025 by Wilson Snyder.
+// SPDX-License-Identifier: CC0-1.0
+
+// verilog_format: off
+`define stop $stop
+`define checkd(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d:  got=%0d exp=%0d\n", `__FILE__,`__LINE__, (gotv), (expv)); `stop; end while(0);
+`define checkh(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d:  got='h%x exp='h%x\n", `__FILE__,`__LINE__, (gotv), (expv)); `stop; end while(0);
+`define checks(gotv,expv) do if ((gotv) != (expv)) begin $write("%%Error: %s:%0d:  got='%s' exp='%s'\n", `__FILE__,`__LINE__, (gotv), (expv)); `stop; end while(0);
+`define checkp(gotv,expv_s) do begin string gotv_s; gotv_s = $sformatf("%p", gotv); if ((gotv_s) != (expv_s)) begin $write("%%Error: %s:%0d:  got='%s' exp='%s'\n", `__FILE__,`__LINE__, (gotv_s), (expv_s)); `stop; end end while(0);
+// verilog_format: on
+
+module t;
+  event e_all_xfers_monitored_tx[4];
+  event e_all_xfers_monitored_rx[4];
+  event e_all_xfers_completed[4];
+
+  task automatic debug(string s);
+    $display("%s", s);
+  endtask
+
+  task run_traffic_per_port(int port_id);
+    fork
+      automatic int id = port_id;
+      begin
+        fork
+          begin
+            @(e_all_xfers_monitored_tx[id]);
+            debug($sformatf("[%0t] [Port %0d] TX done", $time, id));
+          end
+          begin
+            @(e_all_xfers_monitored_rx[id]);
+            debug($sformatf("[%0t] [Port %0d] RX done", $time, id));
+          end
+        join
+
+        ->e_all_xfers_completed[id];
+        $display("[%0t] [Port %0d] ALL done", $time, id);
+      end
+    join_none
+  endtask
+
+  initial begin
+    int i;
+
+    for (i = 0; i < 2; i++) begin
+      run_traffic_per_port(i);
+    end
+
+    #10->e_all_xfers_monitored_tx[0];
+    #10->e_all_xfers_monitored_rx[0];
+
+    #10->e_all_xfers_monitored_tx[1];
+    #10->e_all_xfers_monitored_rx[1];
+
+    @(e_all_xfers_completed[0]);
+    @(e_all_xfers_completed[1]);
+
+    $write("*-* All Finished *-*\n");
+    $finish;
+  end
+
+endmodule