diff --git a/CHANGELOG.md b/CHANGELOG.md
index b78532feb0..ff41df8637 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,8 @@ Full documentation for HIP is available at [rocm.docs.amd.com](https://rocm.docs
     - HIP Extensions APIs for microscaling formats, which are supported on AMD GPUs.
 * New `wptr` and `rptr` values in `ClPrint`, for better logging in dispatch barrier methods.
 * New debug mask, to print precise code object information for logging.
+* The `_sync()` version of crosslane builtins such as `shfl_sync()` and `__reduce_add_sync` are enabled by default. These can be
+disabled by setting the preprocessor macro `HIP_DISABLE_WARP_SYNC_BUILTINS`.
 
 ### Changed
 
diff --git a/hipamd/include/hip/amd_detail/amd_hip_bf16.h b/hipamd/include/hip/amd_detail/amd_hip_bf16.h
index 652bf6db94..a34b75d1a6 100644
--- a/hipamd/include/hip/amd_detail/amd_hip_bf16.h
+++ b/hipamd/include/hip/amd_detail/amd_hip_bf16.h
@@ -663,7 +663,7 @@ __hip_bfloat16 __shfl_xor(MAYBE_UNDEF __hip_bfloat16 var, int lane_mask, int wid
     return tmp.f;
 }
 
-#ifdef HIP_ENABLE_WARP_SYNC_BUILTINS
+#if !defined(HIP_DISABLE_WARP_SYNC_BUILTINS)
 /**
  * \ingroup HIP_INTRINSIC_BFLOAT16_MOVE
  * \brief shfl down warp intrinsic for bfloat16
@@ -771,7 +771,7 @@ __BF16_DEVICE_STATIC__ __hip_bfloat162 __shfl_xor_sync(const unsigned long long
   u.ui = __shfl_xor_sync<unsigned long long, unsigned int>(mask, u.ui, delta, width);
   return u.bf162;
 }
-#endif  // HIP_DISABLE_WARP_SYNC_BUILTINS
+#endif // HIP_DISABLE_WARP_SYNC_BUILTINS
 
 /**
  * \ingroup HIP_INTRINSIC_BFLOAT16_ARITH
diff --git a/hipamd/include/hip/amd_detail/amd_hip_cooperative_groups.h b/hipamd/include/hip/amd_detail/amd_hip_cooperative_groups.h
index 72b605ce80..1025e543d5 100644
--- a/hipamd/include/hip/amd_detail/amd_hip_cooperative_groups.h
+++ b/hipamd/include/hip/amd_detail/amd_hip_cooperative_groups.h
@@ -551,7 +551,7 @@ class coalesced_group : public thread_group {
 
     return __shfl(var, lane, warpSize);
   }
-#ifdef HIP_ENABLE_WARP_SYNC_BUILTINS
+#if !defined(HIP_DISABLE_WARP_SYNC_BUILTINS)
 
   /** \brief Ballot function on group level.
    *
@@ -617,7 +617,7 @@ class coalesced_group : public thread_group {
          __match_all_sync(static_cast<unsigned long long>(coalesced_info.member_mask), value,
                           &pred));
    }
-#endif
+#endif // HIP_DISABLE_WARP_SYNC_BUILTINS
 };
 
 /** \ingroup CooperativeGConstruct 
@@ -819,14 +819,14 @@ template <unsigned int size> class thread_block_tile_base : public tile_base<siz
   friend __CG_QUALIFIER__ coalesced_group
   binary_partition(const thread_block_tile<fsize, fparent>& tgrp, bool pred);
 
-#ifdef HIP_ENABLE_WARP_SYNC_BUILTINS
+#if !defined(HIP_DISABLE_WARP_SYNC_BUILTINS)
   __CG_QUALIFIER__ unsigned long long build_mask() const {
     unsigned long long mask = ~0ull >> (64 - numThreads);
     // thread_rank() gives thread id from 0..thread launch size.
     return mask << (((internal::workgroup::thread_rank() % warpSize) / numThreads) *
                     numThreads);
   }
-#endif
+#endif // HIP_DISABLE_WARP_SYNC_BUILTINS
 
  public:
 
@@ -850,7 +850,7 @@ template <unsigned int size> class thread_block_tile_base : public tile_base<siz
     return (__shfl_xor(var, laneMask, numThreads));
   }
 
-#ifdef HIP_ENABLE_WARP_SYNC_BUILTINS
+#if !defined(HIP_DISABLE_WARP_SYNC_BUILTINS)
   __CG_QUALIFIER__ unsigned long long ballot(int pred) const {
     const auto mask = build_mask();
     return internal::helper::adjust_mask(mask, __ballot_sync(mask, pred));
@@ -869,7 +869,7 @@ template <unsigned int size> class thread_block_tile_base : public tile_base<siz
     const auto mask = build_mask();
     return internal::helper::adjust_mask(mask, __match_all_sync(mask, value, &pred));
   }
-#endif
+#endif // HIP_DISABLE_WARP_SYNC_BUILTINS
 };
 
 /** \brief   User exposed API that captures the state of the parent group pre-partition
@@ -1197,7 +1197,7 @@ __CG_QUALIFIER__ thread_block_tile<size, ParentCGTy> tiled_partition(const Paren
   return impl::tiled_partition_internal<size, ParentCGTy>(g);
 }
 
-#ifdef HIP_ENABLE_WARP_SYNC_BUILTINS
+#if !defined(HIP_DISABLE_WARP_SYNC_BUILTINS)
 
 /** \ingroup CooperativeGConstruct
  *  \brief Binary partition.
diff --git a/hipamd/include/hip/amd_detail/amd_warp_functions.h b/hipamd/include/hip/amd_detail/amd_warp_functions.h
index 463fc06c4b..d8d22ea0be 100644
--- a/hipamd/include/hip/amd_detail/amd_warp_functions.h
+++ b/hipamd/include/hip/amd_detail/amd_warp_functions.h
@@ -122,7 +122,7 @@ unsigned long long int __ballot64(int predicate) {
 }
 
 // See amd_warp_sync_functions.h for an explanation of this preprocessor flag.
-#ifdef HIP_ENABLE_WARP_SYNC_BUILTINS
+#if !defined(HIP_DISABLE_WARP_SYNC_BUILTINS)
 // Since threads in a wave do not make independent progress, __activemask()
 // always returns the exact active mask, i.e, all active threads in the wave.
 __device__
@@ -130,7 +130,7 @@ inline
 unsigned long long __activemask() {
   return __ballot(true);
 }
-#endif // HIP_ENABLE_WARP_SYNC_BUILTINS
+#endif // HIP_DISABLE_WARP_SYNC_BUILTINS
 
 __device__ static inline unsigned int __lane_id() {
     if (warpSize == 32) return __builtin_amdgcn_mbcnt_lo(-1, 0);
diff --git a/hipamd/include/hip/amd_detail/amd_warp_sync_functions.h b/hipamd/include/hip/amd_detail/amd_warp_sync_functions.h
index a47ad1ea9d..c4885868e8 100644
--- a/hipamd/include/hip/amd_detail/amd_warp_sync_functions.h
+++ b/hipamd/include/hip/amd_detail/amd_warp_sync_functions.h
@@ -24,10 +24,11 @@ THE SOFTWARE.
 
 // Warp sync builtins (with explicit mask argument) introduced in ROCm 6.2 as a
 // preview to allow end-users to adapt to the new interface involving 64-bit
-// masks. These are disabled by default, and can be enabled by setting the macro
-// "HIP_ENABLE_WARP_SYNC_BUILTINS". This arrangement also applies to the
+// masks. These are enabled by default, and can be disabled by setting the macro
+// "HIP_DISABLE_WARP_SYNC_BUILTINS". This arrangement also applies to the
 // __activemask() builtin defined in amd_warp_functions.h.
-#ifdef HIP_ENABLE_WARP_SYNC_BUILTINS
+#if !defined(HIP_DISABLE_WARP_SYNC_BUILTINS)
+
 #if !defined(__HIPCC_RTC__)
 #include "amd_warp_functions.h"
 #include "amd_device_functions.h"
@@ -722,5 +723,9 @@ __device__ inline unsigned long long __reduce_xor_sync(MaskT mask, unsigned long
   return __reduce_op_sync(mask, val, op, wfReduce);
 }
 
+#undef __hip_do_sync
+#undef __hip_check_mask
+#undef __hip_adjust_mask_for_wave32
+
 #endif  // HIP_ENABLE_EXTRA_WARP_SYNC_TYPES
-#endif // HIP_ENABLE_WARP_SYNC_BUILTINS
+#endif // HIP_DISABLE_WARP_SYNC_BUILTINS