diff --git a/.gitattributes b/.gitattributes
index 4bfeef1800..0db2b9fdeb 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -8190,6 +8190,7 @@ tests/webtbs/tw4557.pp svneol=native#text/plain
 tests/webtbs/tw4566.pp svneol=native#text/plain
 tests/webtbs/tw4574.pp svneol=native#text/plain
 tests/webtbs/tw4599.pp svneol=native#text/plain
+tests/webtbs/tw4606.pp svneol=native#text/plain
 tests/webtbs/tw4613.pp svneol=native#text/plain
 tests/webtbs/tw4616.pp svneol=native#text/plain
 tests/webtbs/tw4624.pp svneol=native#text/plain
diff --git a/tests/webtbs/tw4606.pp b/tests/webtbs/tw4606.pp
new file mode 100644
index 0000000000..e241536b2d
--- /dev/null
+++ b/tests/webtbs/tw4606.pp
@@ -0,0 +1,11 @@
+{$packset 1}
+type
+  tlettersset=set of 'a'..'z';
+
+begin
+  if sizeof(tlettersset)<>4 then
+    begin
+      writeln(sizeof(tlettersset));
+      halt(1);
+    end;
+end.