note gcc 7.1 stuff

TODO

@@ -1,3 +1,5 @@
+- remove execption specs from libvipsCC, gcc 7.1 will complain about them
+
 - not sure about utf8 error messages on win
 
 - strange: 

libvips/resample/reduceh.cpp

@@ -38,8 +38,8 @@
  */
 
 /*
-#define DEBUG
  */
+#define DEBUG
 
 #ifdef HAVE_CONFIG_H
 #include <config.h>
@@ -487,6 +487,13 @@ vips_reduceh_build( VipsObject *object )
 		for( int i = 0; i < reduceh->n_point; i++ )
 			reduceh->matrixi[x][i] = reduceh->matrixf[x][i] * 
 				VIPS_INTERPOLATE_SCALE;
+
+#ifdef DEBUG
+		printf( "vips_reduceh_build: mask %d\n    ", x ); 
+		for( int i = 0; i < reduceh->n_point; i++ )
+			printf( "%d ", reduceh->matrixi[x][i] );
+		printf( "\n" ); 
+#endif /*DEBUG*/
 	}
 
 	/* Unpack for processing.