Fix `pre_randomize`/`post_randomize` when no randomize (#6122).

Changes

@@ -77,6 +77,7 @@ Verilator 5.037 devel
 * Fix DFG binToOneHot table index missing driver (#6100). [Geza Lore]
 * Fix decoding octal string escapes with 1-2 digits (#6108).
 * Fix colon-divide operator without space (#6121). [Alex Solomatnikov]
+* Fix `pre_randomize`/`post_randomize` when no randomize (#6122). [Alex Solomatnikov]
 * Fix variables declared in fork after taskify (#6126). [Kamil Rakoczy, Antmicro Ltd.]
 * Fix method calls without parenthesis (#6127). [Alex Solomatnikov]
 

src/V3LinkDot.cpp

@@ -3957,6 +3957,7 @@ class LinkDotResolveVisitor final : public VNVisitor {
                     // Resolved in V3Width
                 } else if (nodep->name() == "randomize" || nodep->name() == "srandom"
                            || nodep->name() == "get_randstate" || nodep->name() == "set_randstate"
+                           || nodep->name() == "pre_randomize" || nodep->name() == "post_randomize"
                            || nodep->name() == "rand_mode" || nodep->name() == "constraint_mode") {
                     if (AstClass* const classp = VN_CAST(m_modp, Class)) {
                         nodep->classOrPackagep(classp);

test_regress/t/t_randomize_prepost.v

@@ -4,52 +4,72 @@
 // any use, without warranty, 2022 by Wilson Snyder.
 // SPDX-License-Identifier: CC0-1.0
 
+`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);
+
 typedef enum int {
    RANDOMIZED = 20
 } enumed_t;
 
-class Cls;
-   int       pre;
-   rand enumed_t r;
-   int       post;
+class Base;
+  int m_pre;
+  rand enumed_t r;
+  int m_post;
 
-   function void pre_randomize;
-      if (pre != 0) $stop;
-      $display("%d", r);
-      if (r != enumed_t'(0)) $stop;
-      if (post != 0) $stop;
-      pre = 10;
-   endfunction
+  function void pre_randomize;
+    `checkd(m_pre, 0);
+    `checkd(r, enumed_t'(0));
+    `checkd(m_post, 0);
+    m_pre = 10;
+  endfunction
 
-   function void post_randomize;
-      if (pre != 10) $stop;
-      if (r != RANDOMIZED) $stop;
-      if (post != 0) $stop;
-      post = 30;
-   endfunction
+  function void post_randomize;
+    `checkd(m_pre, 10);
+    `checkd(r, RANDOMIZED);
+    `checkd(m_post, 0);
+    m_post = 30;
+  endfunction
+endclass
+
+class Cls extends Base;
+  int m_cpre;
+  int m_cpost;
+  function void pre_randomize;
+     m_cpre = 111;
+     super.pre_randomize();
+  endfunction
+
+  function void post_randomize;
+     m_cpost = 222;
+     super.post_randomize();
+  endfunction
 endclass
 
 module t (/*AUTOARG*/);
 
-   initial begin
-      Cls c;
-      int rand_result;
+  initial begin
+    Cls c;
+    int rand_result;
 
-      c = new;
-      rand_result = c.randomize();
-      if (rand_result != 1) $stop;
-      if (c.pre != 10) $stop;
-      if (c.r != RANDOMIZED) $stop;
-      if (c.post != 30) $stop;
+    c = new;
+    rand_result = c.randomize();
+    `checkd(rand_result, 1);
+    `checkd(c.m_pre, 10);
+    `checkd(c.m_cpre, 111);
+    `checkd(c.r, RANDOMIZED);
+    `checkd(c.m_post, 30);
+    `checkd(c.m_cpost, 222);
 
-      c = new;
-      rand_result = c.randomize() with { r == RANDOMIZED; };
-      if (rand_result != 1) $stop;
-      if (c.pre != 10) $stop;
-      if (c.r != RANDOMIZED) $stop;
-      if (c.post != 30) $stop;
+    c = new;
+    rand_result = c.randomize() with { r == RANDOMIZED; };
+    `checkd(rand_result, 1);
+    `checkd(c.m_pre, 10);
+    `checkd(c.m_cpre, 111);
+    `checkd(c.r, RANDOMIZED);
+    `checkd(c.m_post, 30);
+    `checkd(c.m_cpost, 222);
 
-      $write("*-* All Finished *-*\n");
-      $finish;
-   end
+    $write("*-* All Finished *-*\n");
+    $finish;
+  end
 endmodule

test_regress/t/t_randomize_prepost_alone.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()

test_regress/t/t_randomize_prepost_alone.v

@@ -0,0 +1,22 @@
+// 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
+
+package uvm_pkg;
+  class uvm_sequence_item;
+  endclass
+endpackage
+
+package tb_cpu_pkg;
+  import uvm_pkg::*;
+  class tb_cpu_seq_item extends uvm_sequence_item;
+    function void pre_randomize();
+      super.pre_randomize();
+    endfunction
+    function void post_randomize();
+      super.post_randomize();
+    endfunction
+  endclass
+endpackage