diff --git a/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp b/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp
--- a/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.lockfree/isalwayslockfree.pass.cpp
@@ -8,9 +8,6 @@
 //
 // UNSUPPORTED: c++03, c++11, c++14
 
-// Fails for 32-bit builds.
-// UNSUPPORTED: LIBCXX-AIX-FIXME
-
 // <atomic>
 
 // static constexpr bool is_always_lock_free;
@@ -33,7 +30,7 @@
 // which causes ATOMIC_LLONG_LOCK_FREE to be defined as '1' in 32-bit builds
 // even though __atomic_always_lock_free returns true for the same type.
 constexpr bool NeedWorkaroundForPR31864 =
-#if defined(__clang__)
+#if defined(__clang__) && !defined(__powerpc__)
 (sizeof(void*) == 4); // Needed on 32 bit builds
 #else
 false;