diff --git a/contrib/coccinelle/array.cocci b/contrib/coccinelle/array.cocci
index d306f6a21e..e71baea00b 100644
--- a/contrib/coccinelle/array.cocci
+++ b/contrib/coccinelle/array.cocci
@@ -107,9 +107,21 @@ type T;
 T *ptr;
 expression n;
 @@
-- memset(ptr, \( 0x0 \| 0 \), n * \( sizeof(T)
--                                 \| sizeof(*ptr)
--                                 \) )
+- memset(ptr, \( 0 \| '\0' \), \( (n) \| n \) * \( sizeof(T)
+-                                               \| sizeof(ptr[...])
+-                                               \| sizeof(*ptr)
+-                                               \) )
++ MEMZERO_ARRAY(ptr, n)
+
+@@
+type T;
+T *ptr;
+expression n;
+@@
+- memset(ptr, \( 0 \| '\0' \), \( sizeof(T)
+-                              \| sizeof(ptr[...])
+-                              \| sizeof(*ptr)
+-                              \) * \( (n) \| n \) )
 + MEMZERO_ARRAY(ptr, n)
 
 @@
@@ -117,7 +129,19 @@ type T;
 T[] ptr;
 expression n;
 @@
-- memset(ptr, \( 0x0 \| 0 \), n * \( sizeof(T)
--                                 \| sizeof(*ptr)
--                                 \) )
+- memset(ptr, \( 0 \| '\0' \), \( (n) \| n \) * \( sizeof(T)
+-                                               \| sizeof(ptr[...])
+-                                               \| sizeof(*ptr)
+-                                               \) )
++ MEMZERO_ARRAY(ptr, n)
+
+@@
+type T;
+T[] ptr;
+expression n;
+@@
+- memset(ptr, \( 0 \| '\0' \), \( sizeof(T)
+-                              \| sizeof(ptr[...])
+-                              \| sizeof(*ptr)
+-                              \) * \( (n) \| n \) )
 + MEMZERO_ARRAY(ptr, n)
diff --git a/diffcore-delta.c b/diffcore-delta.c
index 2de9e9ccff..2b7db39983 100644
--- a/diffcore-delta.c
+++ b/diffcore-delta.c
@@ -135,7 +135,7 @@ static struct spanhash_top *hash_chars(struct repository *r,
 			      st_mult(sizeof(struct spanhash), (size_t)1 << i)));
 	hash->alloc_log2 = i;
 	hash->free = INITIAL_FREE(i);
-	MEMZERO_ARRAY(hash->data, ((size_t)1 << i));
+	MEMZERO_ARRAY(hash->data, (size_t)1 << i);
 
 	n = 0;
 	accum1 = accum2 = 0;
diff --git a/ewah/bitmap.c b/ewah/bitmap.c
index bf878bf876..c378e0ab78 100644
--- a/ewah/bitmap.c
+++ b/ewah/bitmap.c
@@ -46,7 +46,7 @@ static void bitmap_grow(struct bitmap *self, size_t word_alloc)
 {
 	size_t old_size = self->word_alloc;
 	ALLOC_GROW(self->words, word_alloc, self->word_alloc);
-	MEMZERO_ARRAY(self->words + old_size, (self->word_alloc - old_size));
+	MEMZERO_ARRAY(self->words + old_size, self->word_alloc - old_size);
 }
 
 void bitmap_set(struct bitmap *self, size_t pos)
@@ -192,7 +192,7 @@ void bitmap_or_ewah(struct bitmap *self, struct ewah_bitmap *other)
 		self->word_alloc = other_final;
 		REALLOC_ARRAY(self->words, self->word_alloc);
 		MEMZERO_ARRAY(self->words + original_size,
-		              (self->word_alloc - original_size));
+			      self->word_alloc - original_size);
 	}
 
 	ewah_iterator_init(&it, other);