thodg/libgit2

diff --git a/src/pool.c b/src/pool.c
index 0c423dd..16ffa39 100644
--- a/src/pool.c
+++ b/src/pool.c
@@ -36,8 +36,8 @@ int git_pool_global_init(void)
 
 int git_pool_init(git_pool *pool, size_t item_size)
 {
-	assert(pool);
-	assert(item_size >= 1);
+	GIT_ASSERT_ARG(pool);
+	GIT_ASSERT_ARG(item_size >= 1);
 
 	memset(pool, 0, sizeof(git_pool));
 	pool->item_size = item_size;
@@ -131,8 +131,8 @@ static int git_pool__ptr_cmp(const void * a, const void * b)
 
 int git_pool_init(git_pool *pool, size_t item_size)
 {
-	assert(pool);
-	assert(item_size >= 1);
+	GIT_ASSERT_ARG(pool);
+	GIT_ASSERT_ARG(item_size >= 1);
 
 	memset(pool, 0, sizeof(git_pool));
 	pool->item_size = item_size;
@@ -205,7 +205,9 @@ char *git_pool_strndup(git_pool *pool, const char *str, size_t n)
 {
 	char *ptr = NULL;
 
-	assert(pool && str && pool->item_size == sizeof(char));
+	GIT_ASSERT_ARG_WITH_RETVAL(pool, NULL);
+	GIT_ASSERT_ARG_WITH_RETVAL(str, NULL);
+	GIT_ASSERT_ARG_WITH_RETVAL(pool->item_size == sizeof(char), NULL);
 
 	if (n == SIZE_MAX)
 		return NULL;
@@ -220,7 +222,10 @@ char *git_pool_strndup(git_pool *pool, const char *str, size_t n)
 
 char *git_pool_strdup(git_pool *pool, const char *str)
 {
-	assert(pool && str && pool->item_size == sizeof(char));
+	GIT_ASSERT_ARG_WITH_RETVAL(pool, NULL);
+	GIT_ASSERT_ARG_WITH_RETVAL(str, NULL);
+	GIT_ASSERT_ARG_WITH_RETVAL(pool->item_size == sizeof(char), NULL);
+
 	return git_pool_strndup(pool, str, strlen(str));
 }
 
@@ -234,7 +239,8 @@ char *git_pool_strcat(git_pool *pool, const char *a, const char *b)
 	void *ptr;
 	size_t len_a, len_b, total;
 
-	assert(pool && pool->item_size == sizeof(char));
+	GIT_ASSERT_ARG_WITH_RETVAL(pool, NULL);
+	GIT_ASSERT_ARG_WITH_RETVAL(pool->item_size == sizeof(char), NULL);
 
 	len_a = a ? strlen(a) : 0;
 	len_b = b ? strlen(b) : 0;