use -Wextra when compiling and fix some warnings produced by it

4 files changed, 12 insertions, 5 deletions

diff --git a/Makefile b/Makefile
index 5771671..d542721 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@ SOURCES = parse.c atom.c eval.c tokens.c env.c
 OBJECTS = $(SOURCES:.c=.o)
 TEST_OBJECTS = $(foreach obj,$(OBJECTS),test_$(obj))
 
-CFLAGS = -Wall -g
+CFLAGS = -Wall -Wextra -g
 LDFLAGS =
 
 CC = gcc
diff --git a/atom.c b/atom.c
index 43626d8..e3de9ce 100644
--- a/atom.c
+++ b/atom.c
@@ -6,15 +6,19 @@
 #include <string.h>
 #include <stdarg.h>
 
-struct atom true_atom = { ATOM_TRUE };
-struct atom false_atom = { ATOM_FALSE };
-struct atom nil_atom = { ATOM_NIL } ;
+struct atom true_atom;
+struct atom false_atom;
+struct atom nil_atom;
 
 __attribute__((constructor))
 static void setup_builtin_atoms()
 {
     nil_atom.list = calloc(1, sizeof(*nil_atom.list));
     LIST_INIT(nil_atom.list);
+
+    true_atom.type = ATOM_TRUE;
+    false_atom.type = ATOM_FALSE;
+    nil_atom.type = ATOM_NIL;
 }
 
 struct atom *atom_new(char type)
diff --git a/eval.c b/eval.c
index 8325c1f..89b6730 100644
--- a/eval.c
+++ b/eval.c
@@ -75,6 +75,7 @@ struct atom *builtin_quote(struct atom *expr, struct env *env)
 {
     struct list *list = expr->list;
     struct atom *op = LIST_FIRST(list);
+    (void) env;
     return atom_clone(LIST_NEXT(op, entries));
 }
 
@@ -84,6 +85,8 @@ struct atom *builtin_atom(struct atom *expr, struct env *env)
     struct atom *op = LIST_FIRST(list);
     struct atom *a = LIST_NEXT(op, entries);
 
+    (void) env;
+
     if (!a)
         return &nil_atom;
 
diff --git a/repl.c b/repl.c
index c9d6861..ea8d744 100644
--- a/repl.c
+++ b/repl.c
@@ -8,7 +8,7 @@
 #include "atom.h"
 #include "linenoise.h"
 
-int main(int argc, char **argv)
+int main()
 {
     char *line;
     struct env *env;