diff --git a/tests/test/tweaklib1.pp b/tests/test/tweaklib1.pp
index 3b5f2bad12..ed713eb253 100644
--- a/tests/test/tweaklib1.pp
+++ b/tests/test/tweaklib1.pp
@@ -9,7 +9,7 @@
 {$ifdef mswindows}
  {$define supported}
 {$endif win32}
-{$ifdef Unix}
+{$if defined(Unix) and not defined(aix)}
  {$define supported}
 {$endif Unix}
 {$ifndef fpc}
diff --git a/tests/test/tweaklib2.pp b/tests/test/tweaklib2.pp
index a51f9107c7..a4b19714ba 100644
--- a/tests/test/tweaklib2.pp
+++ b/tests/test/tweaklib2.pp
@@ -3,7 +3,7 @@
 {$ifdef mswindows}
  {$define supported}
 {$endif mswindows}
-{$ifdef Unix}
+{$if defined(Unix) and not defined(aix)}
  {$define supported}
 {$endif Unix}
 {$ifndef fpc}