4 files changed, 4 insertions, 6 deletions

diff --git a/makefile b/makefile
index dc2f464..e9c835d 100644
--- a/makefile
+++ b/makefile
@@ -19,7 +19,7 @@ BINS=bin/allocator \
          bin/stack-array \
          bin/stack-linked-list
 
-CFLAGS=-Wall -Werror -Wextra -Wno-unused-function -Wsign-conversion -pedantic -std=c99 -g
+CFLAGS=-Wall -Werror -Wextra -Wno-unused-function -Wsign-conversion -pedantic -std=c17 -g
 
 all: $(BINS)
 
diff --git a/src/avl-tree.c b/src/avl-tree.c
index 5059f3f..fcd9e37 100644
--- a/src/avl-tree.c
+++ b/src/avl-tree.c
@@ -336,10 +336,8 @@ print(struct tree_node *tree)
 }
 
 int
-main()
+main(void)
 {
-
-
 #if 0   /* 1a/b */
         tree = insert(tree, 20);
         tree = insert(tree,  4);
diff --git a/src/list-tail-node.c b/src/list-tail-node.c
index edfcf31..524e5bb 100644
--- a/src/list-tail-node.c
+++ b/src/list-tail-node.c
@@ -171,7 +171,7 @@ list_free(struct list *list)
 /* -->8-- */
 
 int
-main()
+main(void)
 {
         struct list list[1];
 
diff --git a/src/queue.c b/src/queue.c
index 6a472ee..5d25d65 100644
--- a/src/queue.c
+++ b/src/queue.c
@@ -91,7 +91,7 @@ queue_free(struct queue *queue)
 /* -->8-- */
 
 int
-main()
+main(void)
 {
         struct queue queue[1];