Fix loss of warning source content with `line enter (due to earlier commit 472ad90d83).

src/V3FileLine.h

@@ -210,6 +210,7 @@ public:
         lineno(num);
         m_contentLineno = static_cast<unsigned>(num);
     }
+    void contentLinenoFrom(const FileLine* fromp) { m_contentLineno = fromp->m_contentLineno; }
     void lineno(int num) {
         m_firstLineno = num;
         m_lastLineno = num;

src/V3ParseImp.cpp

@@ -85,8 +85,11 @@ void V3ParseImp::lexPpline(const char* textp) {
         lexFileline(newFl);
         lexFileline()->parent(prevFl);
     } else if (enterExit == 2) {  // Exit
+        const FileLine* const prevFl = lexFileline();
         if (FileLine* upFl = lexFileline()->parent()) {
-            lexFileline(upFl);  // Restore warning state to upper file
+            // Must copy upFl as may be existing nodes that use the FileLine value
+            lexFileline(new FileLine{upFl});  // Restore warning state to upper file
+            lexFileline()->contentLinenoFrom(prevFl);
         }
     }
     if (enterExit != -1) {  // Line/fn change

test_regress/t/t_lint_warn_incfile2_bad.out

@@ -1,5 +1,7 @@
 %Warning-WIDTHTRUNC: t/t_lint_warn_incfile2_bad.v:13:17: Operator ASSIGN expects 32 bits on the Assign RHS, but Assign RHS's CONST '64'h1' generates 64 bits.
                                                        : ... note: In instance 't'
+   13 |    int warn_t = 64'h1;   
+      |                 ^~~~~
                      ... For warning description see https://verilator.org/warn/WIDTHTRUNC?v=latest
                      ... Use "/* verilator lint_off WIDTHTRUNC */" and lint_on around source to disable this message.
 %Error: Exiting due to

test_regress/t/t_lint_warn_line_bad.out

@@ -0,0 +1,7 @@
+%Warning-WIDTHTRUNC: the_line_file:13:17: Operator ASSIGN expects 32 bits on the Assign RHS, but Assign RHS's CONST '64'h1' generates 64 bits.
+                                        : ... note: In instance 't'
+   13 |    int warn_t = 64'h1;   
+      |                 ^~~~~
+                     ... For warning description see https://verilator.org/warn/WIDTHTRUNC?v=latest
+                     ... Use "/* verilator lint_off WIDTHTRUNC */" and lint_on around source to disable this message.
+%Error: Exiting due to

test_regress/t/t_lint_warn_line_bad.pl

@@ -0,0 +1,22 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2008 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
+
+scenarios(vlt => 1);
+
+lint(
+    # See also t/t_lint_warn_incfile1_bad
+    # See also t/t_vlt_warn_file_bad
+    verilator_flags2 => ["--no-std"],
+    fails => 1,
+    expect_filename => $Self->{golden_filename},
+    );
+
+ok(1);
+1;

test_regress/t/t_lint_warn_line_bad.v

@@ -0,0 +1,14 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed under the Creative Commons Public Domain, for
+// any use, without warranty, 2023 by Wilson Snyder.
+// SPDX-License-Identifier: CC0-1.0
+
+// Check that `line `__LINE__ still shows proper warning context
+
+`line `__LINE__ "the_line_file" 1
+`line `__LINE__ "the_line_file" 2
+
+module t;
+   int warn_t = 64'h1;  // Not suppressed - should warn
+endmodule

test_regress/t/t_vlt_warn_file_bad.out

@@ -1,5 +1,7 @@
 %Warning-WIDTHTRUNC: t/t_vlt_warn_file_bad.v:11:17: Operator ASSIGN expects 32 bits on the Assign RHS, but Assign RHS's CONST '64'h1' generates 64 bits.
                                                   : ... note: In instance 't'
+   11 |    int warn_t = 64'h1;
+      |                 ^~~~~
                      ... For warning description see https://verilator.org/warn/WIDTHTRUNC?v=latest
                      ... Use "/* verilator lint_off WIDTHTRUNC */" and lint_on around source to disable this message.
 %Error: Exiting due to