   ///     nonnegative. The default is zero.
   ///   - type: The type of `value`.
   @inlinable
+  @_alwaysEmitIntoClient
+  @_silgen_name("_swift_se0349_UnsafeMutableRawPointer_storeBytes")
   public func storeBytes<T>(
+    of value: T, toByteOffset offset: Int = 0, as type: T.Type
+  ) {
+    _debugPrecondition(_isPOD(T.self))
+
+    withUnsafePointer(to: value) { source in
+      // FIXME: to be replaced by _memcpy when conversions are implemented.
+      Builtin.int_memcpy_RawPointer_RawPointer_Int64(
+        (self + offset)._rawValue,
+        source._rawValue,
+        UInt64(MemoryLayout<T>.size)._value,
+        /*volatile:*/ false._value
+      )
+    }
+  }
+
+  // This unavailable implementation uses the expected mangled name
+  // of `storeBytes<T>(of:toByteOffset:as:)`, and provides an entry point for
+  // any binary compiled against the stlib binary for Swift 5.6 and older.
+  @available(*, unavailable)
+  @_silgen_name("sSv10storeBytes2of12toByteOffset2asyx_SixmtlF")
+  @usableFromInline func _legacy_se0349_storeBytes<T>(
+    of value: T, toByteOffset offset: Int = 0, as type: T.Type
+  ) {
+    _legacy_se0349_storeBytes_internal(
+      of: value, toByteOffset: offset, as: T.self
+    )
+  }
+
+  // This is the implementation of `storeBytes` from SwiftStdlib 5.6
+  @_alwaysEmitIntoClient
+  internal func _legacy_se0349_storeBytes_internal<T>(
     of value: T, toByteOffset offset: Int = 0, as type: T.Type
   ) {
     _debugPrecondition(0 == (UInt(bitPattern: self + offset)

        /*volatile:*/ false._value)
    }
  }
  
  /// Copies the specified number of bytes from the given raw pointer's memory
  /// into this pointer's memory.
  ///


  /// Stores the given value's bytes into raw memory at the specified offset.
  ///
  /// The type `T` to be stored must be a trivial type. The memory
  /// must also be uninitialized, initialized to `T`, or initialized to
  /// another trivial type that is layout compatible with `T`.
  ///
  /// After calling `storeBytes(of:toByteOffset:as:)`, the memory is
