diff --git a/tests/core/arch-x86/stalker-x86.c b/tests/core/arch-x86/stalker-x86.c
index 9794d0269..56bf8112c 100644
--- a/tests/core/arch-x86/stalker-x86.c
+++ b/tests/core/arch-x86/stalker-x86.c
@@ -1072,7 +1072,11 @@ static void
 callout_set_cool (GumCpuContext * cpu_context,
                 gpointer user_data)
 {
+#if GLIB_SIZEOF_VOID_P == 8
   cpu_context->rax = 0xc001;
+#else
+  cpu_context->eax = 0xc001;
+#endif
 }
 
 TESTCASE (unfollow_should_be_allowed_before_first_transform)