Add error on class 'function static'.

Changes

@@ -20,6 +20,7 @@ Verilator 5.039 devel
 * Add enum base data type, wire data type, and I/O versus data declaration checking per IEEE.
 * Add error on missing forward declarations (#6206). [Alex Solomatnikov]
 * Add error when trying to assign class object to variable of non-class types (#6237). [Igor Zaworski, Antmicro Ltd.]
+* Add error on class 'function static'.
 * Add `-DVERILATOR=1` definition to compiler flags when using verilated.mk.
 * Support member-level triggers for virtual interfaces (#5166) (#6148). [Yilou Wang]
 * Support unassigned virtual interfaces (#5265) (#6245). [Szymon Gizler, Antmicro Ltd.]

src/V3AstNodeOther.h

@@ -2480,6 +2480,7 @@ public:
     AstNodeFTask* cloneType(const string& name) override {
         return new AstFunc{fileline(), name, nullptr, nullptr};
     }
+    string verilogKwd() const override { return "function"; }
 };
 class AstLet final : public AstNodeFTask {
     // Verilog "let" statement
@@ -2495,6 +2496,7 @@ public:
         return nullptr;
     }
     AstNodeFTask* cloneType(const string& name) override { return new AstLet{fileline(), name}; }
+    string verilogKwd() const override { return "let"; }
 };
 class AstProperty final : public AstNodeFTask {
     // A property inside a module
@@ -2506,6 +2508,7 @@ public:
     AstNodeFTask* cloneType(const string& name) override {
         return new AstProperty{fileline(), name, nullptr};
     }
+    string verilogKwd() const override { return "property"; }
 };
 class AstTask final : public AstNodeFTask {
     // A task inside a module
@@ -2516,6 +2519,7 @@ public:
     AstNodeFTask* cloneType(const string& name) override {
         return new AstTask{fileline(), name, nullptr};
     }
+    string verilogKwd() const override { return "task"; }
 };
 
 // === AstNodeFile ===

src/V3LinkParse.cpp

@@ -198,10 +198,11 @@ class LinkParseVisitor final : public VNVisitor {
                     // DPI-imported functions and properties don't have lifetime specifiers
                     m_lifetime = VLifetime::NONE;
                 }
+                nodep->lifetime(m_lifetime);
                 for (AstNode* itemp = nodep->stmtsp(); itemp; itemp = itemp->nextp()) {
                     AstVar* const varp = VN_CAST(itemp, Var);
                     if (varp && varp->valuep() && varp->lifetime().isNone()
-                        && m_lifetime.isStatic() && !varp->isIO()) {
+                        && nodep->lifetime().isStatic() && !varp->isIO()) {
                         if (VN_IS(m_modp, Module)) {
                             nodep->v3warn(IMPLICITSTATIC,
                                           "Function/task's lifetime implicitly set to static\n"
@@ -223,7 +224,12 @@ class LinkParseVisitor final : public VNVisitor {
                         }
                     }
                 }
-                nodep->lifetime(m_lifetime);
+            }
+            if (nodep->classMethod() && nodep->lifetime().isStatic()) {
+                nodep->v3error("Class function/task cannot be static lifetime ('"
+                               << nodep->verilogKwd() << " static') (IEEE 1800-2023 6.21)\n"
+                               << nodep->warnMore() << "... May have intended 'static "
+                               << nodep->verilogKwd() << "'");
             }
             iterateChildren(nodep);
         }

test_regress/t/t_class_func_static_bad.out

@@ -0,0 +1,10 @@
+%Error: t/t_class_func_static_bad.v:10:17: Class function/task cannot be static lifetime ('task static') (IEEE 1800-2023 6.21)
+                                         : ... May have intended 'static task'
+   10 |     task static task_st(int x);   
+      |                 ^~~~~~~
+        ... See the manual at https://verilator.org/verilator_doc.html?v=latest for more assistance.
+%Error: t/t_class_func_static_bad.v:14:25: Class function/task cannot be static lifetime ('function static') (IEEE 1800-2023 6.21)
+                                         : ... May have intended 'static function'
+   14 |     function static int func_st(int x);   
+      |                         ^~~~~~~
+%Error: Exiting due to

test_regress/t/t_class_func_static_bad.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(fails=True, expect_filename=test.golden_filename)
+
+test.passes()

test_regress/t/t_class_func_static_bad.v

@@ -0,0 +1,23 @@
+// 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 C;
+    task static task_st(int x);  // BAD - methods have automatic lifetime
+      int y;
+      y = 2 * x;
+    endtask
+    function static int func_st(int x);  // BAD - methods have automatic lifetime
+      int y;
+      y = 2 * x;
+      return y;
+    endfunction
+  endclass
+
+  initial $stop;
+
+endmodule

test_regress/t/t_class_static_member_sel.v

@@ -16,7 +16,7 @@ class Bar;
 endclass
 
 class Baz;
-   function static Bar get_bar;
+   static function Bar get_bar;
       Bar b = new;
       return b;
    endfunction
@@ -37,7 +37,7 @@ class ExtendCls extends Cls;
 endclass
 
 class Getter1;
-   function static int get_1;
+   static function int get_1;
       return 1;
    endfunction
 endclass
@@ -54,8 +54,7 @@ class uvm_root;
    endfunction
 endclass
 
-module t (/*AUTOARG*/
+module t (/*AUTOARG*/);
-   );
 
    initial begin
       Foo foo = new;

test_regress/t/t_var_static.v

@@ -22,10 +22,6 @@ class my_cls;
       static int cnt = 0;
       return ++cnt;
    endfunction
-   static function static int get_cnt2;
-      int cnt = 0;
-      return ++cnt;
-   endfunction
 endclass
 
 module t (/*AUTOARG*/
@@ -103,8 +99,6 @@ module t (/*AUTOARG*/
       //
       v = my_cls::get_cnt1(); `checkh(v,   1);
       v = my_cls::get_cnt1(); `checkh(v,   2);
-      v = my_cls::get_cnt2(); `checkh(v,   1);
-      v = my_cls::get_cnt2(); `checkh(v,   2);
       //
    end