diff --git a/libc/bionic/sysconf.cpp b/libc/bionic/sysconf.cpp
index 233e57c..46874cc 100644
--- a/libc/bionic/sysconf.cpp
+++ b/libc/bionic/sysconf.cpp
@@ -317,12 +317,10 @@
 #ifdef _POSIX_THREADS
     case _SC_THREADS:             return _POSIX_THREADS;
 #endif
-#ifdef _POSIX_THREAD_ATTR_STACKADDR
-    case _SC_THREAD_ATTR_STACKADDR:   return _POSIX_THREAD_ATTR_STACKADDR;
-#endif
-#ifdef _POSIX_THREAD_ATTR_STACKSIZE
-    case _SC_THREAD_ATTR_STACKSIZE:   return _POSIX_THREAD_ATTR_STACKSIZE;
-#endif
+
+    case _SC_THREAD_ATTR_STACKADDR:   return -1; // Removed in POSIX 2008
+    case _SC_THREAD_ATTR_STACKSIZE:   return -1; // Removed in POSIX 2008
+
 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
     case _SC_THREAD_PRIORITY_SCHEDULING:  return _POSIX_THREAD_PRIORITY_SCHEDULING;
 #endif