diff --git a/boilerplate/xmalloc.c b/boilerplate/xmalloc.c
index ddd5cccaf..c2cbe2321 100644
--- a/boilerplate/xmalloc.c
+++ b/boilerplate/xmalloc.c
@@ -36,7 +36,7 @@ xmalloc (size_t size)
     void *buf;
 
     buf = malloc (size);
-    if (!buf) {
+    if (buf == NULL && size != 0) {
 	CAIRO_BOILERPLATE_LOG ("Error: Out of memory. Exiting.\n");
 	exit (1);
     }
@@ -50,7 +50,7 @@ xcalloc (size_t nmemb, size_t size)
     void *buf;
 
     buf = calloc (nmemb, size);
-    if (!buf) {
+    if (buf == NULL && nmemb != 0 && size != 0) {
 	CAIRO_BOILERPLATE_LOG ("Error: Out of memory. Exiting\n");
 	exit (1);
     }
@@ -62,7 +62,7 @@ void *
 xrealloc (void *buf, size_t size)
 {
     buf = realloc (buf, size);
-    if (!buf) {
+    if (buf == NULL && size != 0) {
 	CAIRO_BOILERPLATE_LOG ("Error: Out of memory. Exiting\n");
 	exit (1);
     }
diff --git a/src/cairo-image-surface.c b/src/cairo-image-surface.c
index b9c4748e7..553433c8a 100644
--- a/src/cairo-image-surface.c
+++ b/src/cairo-image-surface.c
@@ -922,7 +922,7 @@ _cairo_image_surface_composite_trapezoids (cairo_operator_t	op,
     }
 
     /* Special case adding trapezoids onto a mask surface; we want to avoid
-     * creating an intermediate temporary mask unecessarily.
+     * creating an intermediate temporary mask unnecessarily.
      *
      * We make the assumption here that the portion of the trapezoids
      * contained within the surface is bounded by [dst_x,dst_y,width,height];