diff --git a/configure.ac b/configure.ac
index 948d1e1a..0c3fea3b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -257,9 +257,6 @@ AC_PROG_AWK
 AC_PROG_CC
 AC_PROG_CC_STDC
 AC_PROG_CXX
-AC_C_CONST
-AC_C_RESTRICT
-AX_GCC_VAR_ATTRIBUTE(vector_size)
 AC_PROG_RANLIB
 AC_PROG_INSTALL
 AC_PROG_LN_S
@@ -338,11 +335,34 @@ AC_PROVIDE([AC_LIBTOOL_WIN32_DLL])
 AC_PROG_LIBTOOL
 
 # Checks for typedefs, structures, and compiler characteristics.
+AC_C_RESTRICT
+AX_GCC_VAR_ATTRIBUTE(vector_size)
 AC_C_CONST
 AC_TYPE_MODE_T
 AC_TYPE_OFF_T
 AC_TYPE_SIZE_T
 
+# we need to be able to shuffle vectors in C++
+if test x$ax_cv_have_var_attribute_vector_size = x"yes"; then
+  AC_MSG_CHECKING([for vector shuffle])
+  AC_TRY_COMPILE([
+    typedef float v4f __attribute__((vector_size(4 * sizeof(float))));
+  ],[
+    v4f f; f[3] = 99;
+  ],[
+    AC_MSG_RESULT([yes])
+    have_vector_shuffle=yes
+  ], [
+    AC_MSG_RESULT([no])
+    have_vector_shuffle=no
+  ])
+
+  if test x$have_vector_shuffle = x"yes"; then
+    AC_DEFINE_UNQUOTED(HAVE_VECTOR_SHUFFLE, 1,
+      [define if your C++ can shuffle vectors])
+  fi
+fi
+
 # Checks for library functions.
 AC_FUNC_MEMCMP
 AC_FUNC_MMAP
diff --git a/libvips/conversion/composite.cpp b/libvips/conversion/composite.cpp
index 58196298..4e9f6c00 100644
--- a/libvips/conversion/composite.cpp
+++ b/libvips/conversion/composite.cpp
@@ -489,7 +489,7 @@ vips_composite_blend_mul( VipsBlendMode mode,
 
 /* We have a vector path with gcc's vector attr.
  */
-#ifdef HAVE_VAR_ATTRIBUTE_VECTOR_SIZE
+#ifdef HAVE_VECTOR_SHUFFLE
 /* A vector of four floats.
  */
 typedef float v4f __attribute__((vector_size(4 * sizeof(float))));
@@ -677,7 +677,7 @@ vips_composite_blend_mul_3float( VipsBlendMode mode, v4f &B, float *A_memory )
 
 	B[3] = aR;
 }
-#endif /*HAVE_VAR_ATTRIBUTE_VECTOR_SIZE*/
+#endif /*HAVE_VECTOR_SHUFFLE*/
 
 /* A is the new pixel coming in, B is the double pixel we are accumulating.
  */
@@ -720,7 +720,7 @@ static void vips_combine_pixels( VipsComposite *composite,
 	tq[bands] = B[bands];
 }
 
-#ifdef HAVE_VAR_ATTRIBUTE_VECTOR_SIZE
+#ifdef HAVE_VECTOR_SHUFFLE
 static void 
 vips_combine_pixels_3float( VipsComposite *composite,
 	VipsPel *q, VipsPel **p )
@@ -743,7 +743,7 @@ vips_combine_pixels_3float( VipsComposite *composite,
 	*((v4f *) tq) = R;
 	tq[3] = B[3];
 }
-#endif /*HAVE_VAR_ATTRIBUTE_VECTOR_SIZE*/
+#endif /*HAVE_VECTOR_SHUFFLE*/
 
 static int
 vips_composite_gen( VipsRegion *output_region,
@@ -773,12 +773,12 @@ vips_composite_gen( VipsRegion *output_region,
 		for( x = 0; x < r->width; x++ ) {
 			switch( input_regions[0]->im->BandFmt ) {
 			case VIPS_FORMAT_FLOAT:
-#ifdef HAVE_VAR_ATTRIBUTE_VECTOR_SIZE
+#ifdef HAVE_VECTOR_SHUFFLE
 				if( composite->bands == 3 ) 
 					vips_combine_pixels_3float( composite, 
 						q, p ); 
 				else
-#endif /*HAVE_VAR_ATTRIBUTE_VECTOR_SIZE*/
+#endif /*HAVE_VECTOR_SHUFFLE*/
 					vips_combine_pixels<float>( composite, 
 						q, p );
 				break;