From c15489b7113578742538e301a4a0f7fe204c41ab Mon Sep 17 00:00:00 2001
From: Wilson Snyder <wsnyder@wsnyder.org>
Date: Wed, 17 Sep 2025 23:39:47 -0400
Subject: [PATCH] Fix associative array default type resolution

---
 src/V3Width.cpp                        | 10 ++++++++--
 test_regress/t/t_assoc_default_func.py | 16 ++++++++++++++++
 test_regress/t/t_assoc_default_func.v  | 20 ++++++++++++++++++++
 3 files changed, 44 insertions(+), 2 deletions(-)
 create mode 100755 test_regress/t/t_assoc_default_func.py
 create mode 100644 test_regress/t/t_assoc_default_func.v

diff --git a/src/V3Width.cpp b/src/V3Width.cpp
index c4de5b60c..c99024b8c 100644
--- a/src/V3Width.cpp
+++ b/src/V3Width.cpp
@@ -5008,7 +5008,10 @@ class WidthVisitor final : public VNVisitor {
     }
     void patternAssoc(AstPattern* nodep, AstAssocArrayDType* arrayDtp, AstPatMember* defaultp) {
         AstNode* defaultValuep = nullptr;
-        if (defaultp) defaultValuep = defaultp->lhssp()->unlinkFrBack();
+        if (defaultp) {
+            defaultp->dtypep(arrayDtp->subDTypep());
+            defaultValuep = patternMemberValueIterate(defaultp);
+        }
         AstNodeExpr* newp = new AstConsAssoc{nodep->fileline(), defaultValuep};
         newp->dtypeFrom(arrayDtp);
         for (AstPatMember* patp = VN_AS(nodep->itemsp(), PatMember); patp;
@@ -5037,7 +5040,10 @@ class WidthVisitor final : public VNVisitor {
     void patternWildcard(AstPattern* nodep, AstWildcardArrayDType* arrayDtp,
                          AstPatMember* defaultp) {
         AstNode* defaultValuep = nullptr;
-        if (defaultp) defaultValuep = defaultp->lhssp()->unlinkFrBack();
+        if (defaultp) {
+            defaultp->dtypep(arrayDtp->subDTypep());
+            defaultValuep = patternMemberValueIterate(defaultp);
+        }
         AstNode* newp = new AstConsWildcard{nodep->fileline(), defaultValuep};
         newp->dtypeFrom(arrayDtp);
         for (AstPatMember* patp = VN_AS(nodep->itemsp(), PatMember); patp;
diff --git a/test_regress/t/t_assoc_default_func.py b/test_regress/t/t_assoc_default_func.py
new file mode 100755
index 000000000..cca4c9e73
--- /dev/null
+++ b/test_regress/t/t_assoc_default_func.py
@@ -0,0 +1,16 @@
+#!/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('linter')
+
+test.lint()
+
+test.passes()
diff --git a/test_regress/t/t_assoc_default_func.v b/test_regress/t/t_assoc_default_func.v
new file mode 100644
index 000000000..e4a3be8f8
--- /dev/null
+++ b/test_regress/t/t_assoc_default_func.v
@@ -0,0 +1,20 @@
+// 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
+
+module t;
+  class param_comp #(
+      type T = bit
+  );
+    static function int get_type();
+    endfunction
+  endclass
+
+  class test;
+    virtual function void check_phase();
+      int m_param_comp_bit_expect_wrapper[string] = '{default: param_comp#(bit)::get_type()};
+    endfunction
+  endclass
+endmodule