diff --git a/tests/unistd_test.cpp b/tests/unistd_test.cpp
index 96d66e4..f5c0524 100644
--- a/tests/unistd_test.cpp
+++ b/tests/unistd_test.cpp
@@ -576,7 +576,7 @@
   EXPECT_EQ(_POSIX_VERSION, _POSIX_THREAD_ATTR_STACKSIZE);
   EXPECT_EQ(0, _POSIX_THREAD_CPUTIME);       // Use sysconf to detect support at runtime.
   EXPECT_GT(_POSIX_THREAD_DESTRUCTOR_ITERATIONS, 0);
-  EXPECT_GT(_POSIX_THREAD_KEYS_MAX, 0);
+  EXPECT_EQ(_POSIX_THREAD_KEYS_MAX, 128);
   EXPECT_EQ(_POSIX_VERSION, _POSIX_THREAD_PRIORITY_SCHEDULING);
   EXPECT_EQ(_POSIX_VERSION, _POSIX_THREAD_PRIO_INHERIT);
   EXPECT_EQ(_POSIX_VERSION, _POSIX_THREAD_PRIO_PROTECT);