Fix bug https://trac.osgeo.org/grass/ticket/369

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@39889 15284696-431f-4ddb-bdfa-cd5b030d7da7

lib/raster/get_row.c

@@ -1076,7 +1076,7 @@ static void get_null_value_row_gdal(int fd, char *flags, int row)
 
     for (i = 0; i < G__.window.cols; i++)
 	/* note: using == won't work if the null value is NaN */
-	flags[i] =
+	flags[i] = !fcb->col_map[i] ||
 	    memcmp(&tmp_buf[i], &fcb->gdal->null_val, sizeof(DCELL)) == 0;
 
     G_free(tmp_buf);