diff --git a/compiler/src/dmd/traits.d b/compiler/src/dmd/traits.d
index 21ec3ab0e1..fbb77b0ffd 100644
--- a/compiler/src/dmd/traits.d
+++ b/compiler/src/dmd/traits.d
@@ -947,15 +947,24 @@ Expression semanticTraits(TraitsExp e, Scope* sc)
          */
 
         Dsymbol sym = getDsymbol(o);
+
+        if (sym && e.ident == Id.hasMember)
+        {
+            if (auto sm = sym.search(e.loc, id))
+                return True();
+
+            // https://issues.dlang.org/show_bug.cgi?id=23951
+            if (auto decl = sym.isDeclaration())
+            {
+                ex = typeDotIdExp(e.loc, decl.type, id);
+                goto doSemantic;
+            }
+        }
+
         if (auto t = isType(o))
             ex = typeDotIdExp(e.loc, t, id);
         else if (sym)
         {
-            if (e.ident == Id.hasMember)
-            {
-                if (auto sm = sym.search(e.loc, id))
-                    return True();
-            }
             ex = new DsymbolExp(e.loc, sym);
             ex = new DotIdExp(e.loc, ex, id);
         }
@@ -966,7 +975,7 @@ Expression semanticTraits(TraitsExp e, Scope* sc)
             e.error("invalid first argument");
             return ErrorExp.get();
         }
-
+    doSemantic:
         // ignore symbol visibility and disable access checks for these traits
         Scope* scx = sc.push();
         scx.flags |= SCOPE.ignoresymbolvisibility | SCOPE.noaccesscheck;
diff --git a/compiler/test/compilable/test23951.d b/compiler/test/compilable/test23951.d
new file mode 100644
index 0000000000..e09a3d7b5d
--- /dev/null
+++ b/compiler/test/compilable/test23951.d
@@ -0,0 +1,10 @@
+// https://issues.dlang.org/show_bug.cgi?id=23951
+
+struct S { int x; }
+struct T { S a; alias a this; }
+struct U { T t; }
+static assert(__traits(hasMember, T, "x"));
+static assert(__traits(hasMember, T.init, "x"));
+static assert(__traits(hasMember, U.init.t, "x"));
+static assert(__traits(hasMember, U.t, "a"));
+static assert(__traits(hasMember, U.t, "x"));
diff --git a/compiler/test/fail_compilation/test23279.d b/compiler/test/fail_compilation/test23279.d
new file mode 100644
index 0000000000..43f2d44a07
--- /dev/null
+++ b/compiler/test/fail_compilation/test23279.d
@@ -0,0 +1,14 @@
+// https://issues.dlang.org/show_bug.cgi?id=23279
+
+/*
+TEST_OUTPUT:
+---
+fail_compilation/test23279.d(13): Error: undefined identifier `Sth`
+---
+*/
+
+class Tester
+{
+    enum a = __traits(hasMember, Tester, "setIt");
+    void setIt(Sth sth){}
+}