more simpler approach

Author: abulgit

compiler/src/dmd/statementsem.d

@@ -1973,30 +1973,19 @@ Statement statementSemanticVisit(Statement s, Scope* sc)
                         return setError();
                     }
                 }
-            }
-
-            if (ed && ss.cases.length < ed.members.length)
-            {
-                // Add a check for incomplete enum declaration to prevent segfault
-                // when the enum is being defined while it's referenced in a final switch
-                bool isEnumIncomplete = false;
-                foreach (es; *ed.members)
-                {
-                    EnumMember em = es.isEnumMember();
-                    if (em && em.value is null)
-                    {
-                        isEnumIncomplete = true;
-                        break;
-                    }
-                }
 
-                if (isEnumIncomplete)
+                // Check if enum semantic analysis is not yet complete
+                if (ed.semanticRun < PASS.semanticdone)
                 {
                     error(ss.loc, "cannot use `final switch` on enum `%s` while it is being defined", ed.toChars());
                     sc.pop();
                     return setError();
                 }
+            }
 
+            if (ed && ss.cases.length < ed.members.length)
+            {
+                // Remove the old check for incomplete enum members
                 int missingMembers = 0;
                 const maxShown = global.params.v.errorSupplementCount();
             Lmembers:

compiler/test/fail_compilation/fix20867.d

@@ -1,13 +1,11 @@
 /*
 TEST_OUTPUT:
 ---
-fail_compilation/fix20867.d(16): Error: cannot use `final switch` on enum `E` while it is being defined
-fail_compilation/fix20867.d(31): Error: cannot use `final switch` on enum `E2` while it is being defined
-fail_compilation/fix20867.d(63): Error: cannot use `final switch` on enum `E4` while it is being defined
+fail_compilation/fix20867.d(14): Error: cannot use `final switch` on enum `E` while it is being defined
 ---
 */
 
-// Test case 1: The exact scenario Issue(From Github Issue(#20867))
+// Test case from Issue #20867
 enum E
 {
     a = 3,
@@ -20,51 +18,3 @@ enum E
         return 4;
     } ()
 }
-
-// Test case 2: Variation with multiple members
-enum E2
-{
-    x = 10,
-    y = 20,
-    z = () {
-        E2 e;
-        final switch (e)  // Should also error out safely
-        {
-            case E2.x: return 30;
-            case E2.y: return 40;
-        }
-    } ()
-}
-
-// Test case 3: Regular use of final switch (this should still compile)
-enum E3
-{
-    p = 1,
-    q = 2
-}
-
-void testE3()
-{
-    E3 e = E3.p;
-    final switch (e)
-    {
-        case E3.p: break;
-        case E3.q: break;
-    }
-}
-
-// Test case 4: Nested circular reference
-enum E4
-{
-    r = 5,
-    s = () {
-        int foo() {
-            E4 e;
-            final switch (e)  // Should error out
-            {
-                case E4.r: return 6;
-            }
-        }
-        return foo();
-    } ()
-}