diff --git a/zathura/adjustment.c b/zathura/adjustment.c
index 1cd31b3..9a10da5 100644
--- a/zathura/adjustment.c
+++ b/zathura/adjustment.c
@@ -13,7 +13,7 @@ page_calc_height_width(zathura_document_t* document, double height,
   g_return_val_if_fail(document != NULL && page_height != NULL && page_width != NULL, 0.0);
 
   double scale = zathura_document_get_scale(document);
-  if (rotate && zathura_document_get_rotation(document) % 180) {
+  if (rotate == true && zathura_document_get_rotation(document) % 180 != 0) {
     *page_width  = round(height * scale);
     *page_height = round(width  * scale);
     scale = MAX(*page_width / height, *page_height / width);
diff --git a/zathura/render.c b/zathura/render.c
index f18ceb4..de750cb 100644
--- a/zathura/render.c
+++ b/zathura/render.c
@@ -845,7 +845,7 @@ render_all(zathura_t* zathura)
 
   /* unmark all pages */
   const unsigned int number_of_pages = zathura_document_get_number_of_pages(zathura->document);
-  for (unsigned int page_id = 0; page_id < number_of_pages; page_id++) {
+  for (unsigned int page_id = 0; page_id < number_of_pages; ++page_id) {
     zathura_page_t* page = zathura_document_get_page(zathura->document,
         page_id);
     unsigned int page_height = 0, page_width = 0;