kc3-lang/kc3

diff --git a/libkc3/buf_parse_s.c.in b/libkc3/buf_parse_s.c.in
index c3af3c7..5c5a767 100644
--- a/libkc3/buf_parse_s.c.in
+++ b/libkc3/buf_parse_s.c.in
@@ -27,8 +27,8 @@ sw buf_parse_s_bits$ (s_buf *buf, s_bits$ *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  s_bits$ tmp;
-  s_bits$ tmp1;
+  s_bits$ tmp = 0;
+  s_bits$ tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_s16.c b/libkc3/buf_parse_s16.c
index e761b83..710b38b 100644
--- a/libkc3/buf_parse_s16.c
+++ b/libkc3/buf_parse_s16.c
@@ -27,8 +27,8 @@ sw buf_parse_s16 (s_buf *buf, s16 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  s16 tmp;
-  s16 tmp1;
+  s16 tmp = 0;
+  s16 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_s32.c b/libkc3/buf_parse_s32.c
index f836295..266976a 100644
--- a/libkc3/buf_parse_s32.c
+++ b/libkc3/buf_parse_s32.c
@@ -27,8 +27,8 @@ sw buf_parse_s32 (s_buf *buf, s32 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  s32 tmp;
-  s32 tmp1;
+  s32 tmp = 0;
+  s32 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_s64.c b/libkc3/buf_parse_s64.c
index a0d5e76..c9813d8 100644
--- a/libkc3/buf_parse_s64.c
+++ b/libkc3/buf_parse_s64.c
@@ -27,8 +27,8 @@ sw buf_parse_s64 (s_buf *buf, s64 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  s64 tmp;
-  s64 tmp1;
+  s64 tmp = 0;
+  s64 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_s8.c b/libkc3/buf_parse_s8.c
index af12f83..0873e8f 100644
--- a/libkc3/buf_parse_s8.c
+++ b/libkc3/buf_parse_s8.c
@@ -27,8 +27,8 @@ sw buf_parse_s8 (s_buf *buf, s8 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  s8 tmp;
-  s8 tmp1;
+  s8 tmp = 0;
+  s8 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_sw.c b/libkc3/buf_parse_sw.c
index f564f22..5852ce8 100644
--- a/libkc3/buf_parse_sw.c
+++ b/libkc3/buf_parse_sw.c
@@ -27,8 +27,8 @@ sw buf_parse_sw (s_buf *buf, sw *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  sw tmp;
-  sw tmp1;
+  sw tmp = 0;
+  sw tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_u.c.in b/libkc3/buf_parse_u.c.in
index 14f35ae..1d95e72 100644
--- a/libkc3/buf_parse_u.c.in
+++ b/libkc3/buf_parse_u.c.in
@@ -27,8 +27,8 @@ sw buf_parse_u_bits$ (s_buf *buf, u_bits$ *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  u_bits$ tmp;
-  u_bits$ tmp1;
+  u_bits$ tmp = 0;
+  u_bits$ tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_u16.c b/libkc3/buf_parse_u16.c
index c7581f7..83f2aa3 100644
--- a/libkc3/buf_parse_u16.c
+++ b/libkc3/buf_parse_u16.c
@@ -27,8 +27,8 @@ sw buf_parse_u16 (s_buf *buf, u16 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  u16 tmp;
-  u16 tmp1;
+  u16 tmp = 0;
+  u16 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_u32.c b/libkc3/buf_parse_u32.c
index 0db98e6..9f34216 100644
--- a/libkc3/buf_parse_u32.c
+++ b/libkc3/buf_parse_u32.c
@@ -27,8 +27,8 @@ sw buf_parse_u32 (s_buf *buf, u32 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  u32 tmp;
-  u32 tmp1;
+  u32 tmp = 0;
+  u32 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_u64.c b/libkc3/buf_parse_u64.c
index a20ea69..bd53f7e 100644
--- a/libkc3/buf_parse_u64.c
+++ b/libkc3/buf_parse_u64.c
@@ -27,8 +27,8 @@ sw buf_parse_u64 (s_buf *buf, u64 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  u64 tmp;
-  u64 tmp1;
+  u64 tmp = 0;
+  u64 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_u8.c b/libkc3/buf_parse_u8.c
index f2a8430..279290b 100644
--- a/libkc3/buf_parse_u8.c
+++ b/libkc3/buf_parse_u8.c
@@ -27,8 +27,8 @@ sw buf_parse_u8 (s_buf *buf, u8 *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  u8 tmp;
-  u8 tmp1;
+  u8 tmp = 0;
+  u8 tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_parse_uw.c b/libkc3/buf_parse_uw.c
index 7d5accb..0621cd7 100644
--- a/libkc3/buf_parse_uw.c
+++ b/libkc3/buf_parse_uw.c
@@ -27,8 +27,8 @@ sw buf_parse_uw (s_buf *buf, uw *dest)
   sw r1;
   sw result = 0;
   s_buf_save save;
-  uw tmp;
-  uw tmp1;
+  uw tmp = 0;
+  uw tmp1 = 0;
   assert(buf);
   assert(dest);
   buf_save_init(buf, &save);
diff --git a/libkc3/buf_rw.c b/libkc3/buf_rw.c
index f593bfe..e8cf2d9 100644
--- a/libkc3/buf_rw.c
+++ b/libkc3/buf_rw.c
@@ -32,7 +32,7 @@ void buf_rw_fd_close (s_buf_rw *buf_rw)
 
 s_buf_rw * buf_rw_fd_open (s_buf_rw *buf_rw, s32 fd)
 {
-  s_buf_rw tmp;
+  s_buf_rw tmp = {0};
   assert(buf_rw);
   tmp = *buf_rw;
   if (! buf_fd_open_r(&tmp.r, fd))
diff --git a/libkc3/call.c b/libkc3/call.c
index ff199a3..7be110a 100644
--- a/libkc3/call.c
+++ b/libkc3/call.c
@@ -159,7 +159,7 @@ s_call * call_init_op_unary (s_call *call)
 s_str * call_inspect (const s_call *call, s_str *dest)
 {
   sw size;
-  s_buf tmp;
+  s_buf tmp = {0};
   size = buf_inspect_call_size(call);
   if (size < 0) {
     assert(! "error");
diff --git a/libkc3/cfn.c b/libkc3/cfn.c
index 59930af..468f95d 100644
--- a/libkc3/cfn.c
+++ b/libkc3/cfn.c
@@ -36,8 +36,8 @@ s_tag * cfn_apply (s_cfn *cfn, s_list *args, s_tag *dest)
   sw i = 0;
   sw num_args;
   void *result = NULL;
-  s_tag tmp;
-  s_tag tmp2;
+  s_tag tmp = {0};
+  s_tag tmp2 = {0};
   assert(cfn);
   assert(cfn->arity == cfn->cif.nargs);
   num_args = list_length(args);
diff --git a/libkc3/compare.c b/libkc3/compare.c
index 1c89c4c..01dfa6f 100644
--- a/libkc3/compare.c
+++ b/libkc3/compare.c
@@ -555,8 +555,8 @@ s8 compare_sym (const s_sym *a, const s_sym *b)
 
 s8 compare_tag (const s_tag *a, const s_tag *b) {
   s8 r;
-  s_integer tmp;
-  s_integer tmp2;
+  s_integer tmp = {0};
+  s_integer tmp2 = {0};
   if (a == b)
     return 0;
   if (!a ||
diff --git a/libkc3/complex.c b/libkc3/complex.c
index 44b7797..ce1ec7e 100644
--- a/libkc3/complex.c
+++ b/libkc3/complex.c
@@ -326,7 +326,7 @@ s_tag * complex_norm (const s_complex *c, s_tag *dest)
 {
   s_complex d;
   s_tag sum;
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(c);
   tag_mul(&c->x, &c->x, &d.x);
   tag_mul(&c->y, &c->y, &d.y);
diff --git a/libkc3/cow.c b/libkc3/cow.c
index 9b8a67f..7327388 100644
--- a/libkc3/cow.c
+++ b/libkc3/cow.c
@@ -37,7 +37,7 @@ void cow_delete (s_cow *cow)
 
 s_cow * cow_freeze (s_cow *cow)
 {
-  s_list *tmp;
+  s_list *tmp = NULL;
   assert(cow);
   assert(cow->list);
   tmp = list_new_tag_copy(&cow->list->tag, cow->list);
@@ -49,7 +49,7 @@ s_cow * cow_freeze (s_cow *cow)
 
 s_cow * cow_freeze_copy (s_cow *cow, const s_tag *src)
 {
-  s_list *tmp;
+  s_list *tmp = NULL;
   assert(cow);
   assert(cow->list);
   tmp = list_new_tag_copy(src, list_next(cow->list));
@@ -97,7 +97,7 @@ s_cow * cow_init_cast (s_cow *cow, const s_sym * const *type,
                        const s_tag *tag)
 {
   void *data;
-  s_cow tmp;
+  s_cow tmp = {0};
   assert(tag);
   assert(type);
   assert(tag);
@@ -260,7 +260,7 @@ s_tag * cow_read_write (s_cow *cow)
 
 s_cow * cow_thaw (s_cow *cow)
 {
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(cow);
   assert(cow->list);
   assert(list_next(cow->list));
@@ -278,7 +278,7 @@ s_cow * cow_thaw (s_cow *cow)
 
 s_cow * cow_thaw_copy (s_cow *cow, const s_tag *src)
 {
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(cow);
   assert(cow->list);
   assert(src);
diff --git a/libkc3/env.c b/libkc3/env.c
index 354b4f7..b642f26 100644
--- a/libkc3/env.c
+++ b/libkc3/env.c
@@ -525,7 +525,7 @@ bool env_eval_block (s_env *env, const s_block *block, s_tag *dest)
 {
   uw i = 0;
   bool r;
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(env);
   assert(block);
   assert(dest);
@@ -736,7 +736,7 @@ bool env_eval_call_fn_args (s_env *env, const s_fn *fn,
 bool env_eval_call_resolve (s_env *env, s_call *call)
 {
   bool b;
-  s_call tmp;
+  s_call tmp = {0};
   const s_tag *value;
   assert(env);
   assert(call);
@@ -792,7 +792,7 @@ bool env_eval_call_resolve (s_env *env, s_call *call)
 
 bool env_eval_cfn (s_env *env, const s_cfn *cfn, s_tag *dest)
 {
-  s_cfn tmp;
+  s_cfn tmp = {0};
   assert(cfn);
   assert(dest);
   (void) env;
@@ -854,7 +854,7 @@ bool env_eval_equal_cow (s_env *env, const s_cow *a,
                          const s_cow *b, s_cow **dest)
 {
   s8 r;
-  s_cow *tmp;
+  s_cow *tmp = {0};
   assert(env);
   assert(a);
   assert(b);
@@ -928,7 +928,7 @@ bool env_eval_equal_map (s_env *env, bool macro, const s_map *a,
   const s_map *c;
   uw i;
   uw j;
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(env);
   assert(a);
   assert(b);
@@ -1158,7 +1158,7 @@ bool env_eval_equal_tuple (s_env *env, bool macro, const s_tuple *a,
                            const s_tuple *b, s_tuple *dest)
 {
   uw i;
-  s_tuple tmp;
+  s_tuple tmp = {0};
   assert(env);
   assert(a);
   assert(b);
@@ -1197,7 +1197,7 @@ bool env_eval_fn (s_env *env, const s_fn *fn, s_tag *dest)
 bool env_eval_ident (s_env *env, const s_ident *ident, s_tag *dest)
 {
   const s_tag *tag;
-  s_tag tmp;
+  s_tag tmp = {0};
   s_ident tmp_ident;
   assert(env);
   assert(ident);
@@ -1219,8 +1219,8 @@ bool env_eval_ident (s_env *env, const s_ident *ident, s_tag *dest)
 
 bool env_eval_ident_is_bound (s_env *env, const s_ident *ident)
 {
-  s_ident tmp_ident;
-  s_tag tmp;
+  s_ident tmp_ident = {0};
+  s_tag tmp = {0};
   assert(env);
   assert(ident);
   if (env_frames_get(env, ident->sym))
@@ -1261,7 +1261,7 @@ bool env_eval_list (s_env *env, const s_list *list, s_tag *dest)
 
 bool env_eval_map (s_env *env, const s_map *map, s_tag *dest)
 {
-  s_map tmp;
+  s_map tmp = {0};
   uw i = 0;
   assert(env);
   assert(map);
@@ -1336,7 +1336,7 @@ bool env_eval_quote_array (s_env *env, const s_array *array,
 bool env_eval_quote_block (s_env *env, const s_block *block, s_tag *dest)
 {
   uw i = 0;
-  s_block tmp;
+  s_block tmp = {0};
   assert(env);
   assert(block);
   assert(dest);
@@ -1433,7 +1433,7 @@ bool env_eval_quote_cow (s_env *env, const s_cow *cow,
 
 bool env_eval_quote_list (s_env *env, const s_list *list, s_tag *dest)
 {
-  s_list *next;
+  s_list *next = NULL;
   s_list *tmp = NULL;
   s_list **tail = &tmp;
   assert(env);
@@ -1461,7 +1461,7 @@ bool env_eval_quote_list (s_env *env, const s_list *list, s_tag *dest)
 
 bool env_eval_quote_map (s_env *env, const s_map *map, s_tag *dest)
 {
-  s_map tmp;
+  s_map tmp = {0};
   uw i = 0;
   assert(env);
   assert(map);
@@ -1605,7 +1605,7 @@ bool env_eval_quote_tag (s_env *env, const s_tag *tag, s_tag *dest)
 bool env_eval_quote_tuple (s_env *env, const s_tuple *tuple, s_tag *dest)
 {
   uw i = 0;
-  s_tuple tmp;
+  s_tuple tmp = {0};
   assert(env);
   assert(tuple);
   assert(dest);
@@ -1626,7 +1626,7 @@ bool env_eval_quote_tuple (s_env *env, const s_tuple *tuple, s_tag *dest)
 bool env_eval_quote_unquote (s_env *env, const s_unquote *unquote, s_tag *dest)
 {
   bool r;
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(env);
   assert(unquote);
   assert(dest);
@@ -1654,7 +1654,7 @@ bool env_eval_quote_unquote (s_env *env, const s_unquote *unquote, s_tag *dest)
 bool env_eval_str (s_env *env, const s_str *str, s_tag *dest)
 {
   bool r = true;
-  s_tag tmp;
+  s_tag tmp = {0};
   if (! str_parse_eval(str, &tmp)) {
     err_puts("env_eval_str: invalid Str");
     assert(! "env_eval_str: invalid Str");
@@ -1818,7 +1818,7 @@ bool env_eval_tag (s_env *env, const s_tag *tag, s_tag *dest)
 bool env_eval_tuple (s_env *env, const s_tuple *tuple, s_tag *dest)
 {
   uw i = 0;
-  s_tuple tmp;
+  s_tuple tmp = {0};
   assert(env);
   assert(tuple);
   assert(dest);
@@ -1901,7 +1901,7 @@ s_tag * env_ident_get (s_env *env, const s_ident *ident, s_tag *dest)
   s_tag tag_symbol;
   s_tag tag_symbol_value;
   s_tag tag_var;
-  s_tag tmp;
+  s_tag tmp = {0};
   module = ident->module;
   if (! module) {
     if (! env_sym_search_modules(env, ident->sym, &module) ||
@@ -2001,7 +2001,7 @@ s_ident * env_ident_resolve_module (s_env *env,
                                     const s_ident *ident,
                                     s_ident *dest)
 {
-  s_ident tmp;
+  s_ident tmp = {0};
   assert(env);
   assert(ident);
   tmp = *ident;
@@ -2138,7 +2138,7 @@ s_tag * env_let (s_env *env, const s_tag *tag, const s_block *block,
 {
   uw i;
   const s_map *map;
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(env);
   assert(tag);
   assert(block);
@@ -2196,7 +2196,7 @@ bool env_load (s_env *env, const s_str *path)
   s_tag  file_path_save;
   sw r;
   s_tag tag = {0};
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(env);
   assert(path);
   if (! buf_init_alloc(&buf, BUF_SIZE))
@@ -2537,8 +2537,8 @@ s_list ** env_module_search_modules (s_env *env,
                                      const s_sym * const *module,
                                      s_list **dest)
 {
-  s_list *tmp;
-  s_list *tmp2;
+  s_list *tmp = {0};
+  s_list *tmp2 = {0};
   assert(env);
   (void) env;
   if (! module || ! *module) {
@@ -2611,7 +2611,7 @@ bool * env_operator_find (s_env *env, const s_ident *op, bool *dest)
 s_ident * env_operator_ident (s_env *env, const s_ident *op,
                               s_ident *dest)
 {
-  s_ident tmp;
+  s_ident tmp = {0};
   assert(env);
   assert(op);
   assert(dest);
@@ -2690,7 +2690,7 @@ s_ident * env_operator_resolve (s_env *env, const s_ident *op,
   s_tag tag_var;
   s_tag tag_sym_sym;
   s_tag tag_sym_value;
-  s_ident tmp;
+  s_ident tmp = {0};
   env_ident_resolve_module(env, op, &tmp);
   tag_init_sym(&tag_arity, &g_sym_arity);
   tag_init_u8( &tag_arity_u8, arity);
@@ -3003,7 +3003,7 @@ f_clean env_struct_type_get_clean (s_env *env, const s_sym *module)
   s_tag tag_clean;
   s_tag tag_module;
   s_tag tag_var;
-  f_clean tmp;
+  f_clean tmp = {0};
   const s_sym *type;
   tag_init_sym(&tag_module, module);
   tag_init_sym(&tag_clean, &g_sym_clean);
@@ -3050,7 +3050,7 @@ s_list ** env_struct_type_get_spec (s_env *env,
   s_tag tag_defstruct;
   s_tag tag_module;
   s_tag tag_var;
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(env);
   assert(module);
   assert(dest);
@@ -3106,7 +3106,7 @@ bool * env_struct_type_has_spec (s_env *env, const s_sym *module,
 
 bool env_tag_ident_is_bound (s_env *env, const s_tag *tag)
 {
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(tag);
   assert(tag->type == TAG_IDENT);
   return tag->type == TAG_IDENT &&
@@ -3117,7 +3117,7 @@ bool env_tag_ident_is_bound (s_env *env, const s_tag *tag)
 s_tag * env_unwind_protect (s_env *env, s_tag *protected, s_block *cleanup,
                             s_tag *dest)
 {
-  s_tag tmp;
+  s_tag tmp = {0};
   s_unwind_protect unwind_protect;
   assert(env);
   assert(protected);
diff --git a/libkc3/facts.c b/libkc3/facts.c
index 2326de5..01353b8 100644
--- a/libkc3/facts.c
+++ b/libkc3/facts.c
@@ -43,7 +43,7 @@ static sw facts_open_log (s_facts *facts, s_buf *buf);
 
 const s_fact * facts_add_fact (s_facts *facts, const s_fact *fact)
 {
-  s_fact tmp;
+  s_fact tmp = {0};
   s_fact *f = NULL;
   s_set_item__fact *item;
   assert(facts);
diff --git a/libkc3/file.c b/libkc3/file.c
index 82a749e..7129e9d 100644
--- a/libkc3/file.c
+++ b/libkc3/file.c
@@ -138,7 +138,7 @@ s_tag * file_mtime (const s_str *path, s_tag *dest)
 #if HAVE_STAT_MTIM
   return time_to_tag(&sb.st_mtim, dest);
 #else
-  s_time tmp;
+  s_time tmp = {0};
   tmp.tv_sec = sb.st_mtime;
   tmp.tv_nsec = 0;
   return time_to_tag(&tmp, dest);
@@ -185,7 +185,7 @@ s_str * file_search (const s_str *suffix, const s_sym *mode,
   sw r;
   s_buf_save save;
   const s_str *str;
-  s_str tmp;
+  s_str tmp = {0};
   buf_init(&buf, false, PATH_MAX, buf_s);
   if ((r = buf_write_str(&buf, &g_kc3_env.argv0_dir)) < 0)
     return NULL;
diff --git a/libkc3/fn_clause.c b/libkc3/fn_clause.c
index c30dd05..64cbcab 100644
--- a/libkc3/fn_clause.c
+++ b/libkc3/fn_clause.c
@@ -61,9 +61,8 @@ s_fn_clause * fn_clause_new (s_fn_clause *next_clause)
 
 s_fn_clause * fn_clause_new_copy (const s_fn_clause *src)
 {
-  s_fn_clause *tmp;
-  s_fn_clause **tail;
-  tmp = NULL;
+  s_fn_clause *tmp = NULL;
+  s_fn_clause **tail = NULL;
   tail = &tmp;
   while (src) {
     *tail = fn_clause_new(NULL);
diff --git a/libkc3/ident.c b/libkc3/ident.c
index c2263b9..c38aa46 100644
--- a/libkc3/ident.c
+++ b/libkc3/ident.c
@@ -72,7 +72,7 @@ s_ident * ident_init (s_ident *ident, const s_sym *module,
 
 s_ident * ident_init_1 (s_ident *ident, const char *p)
 {
-  s_str tmp;
+  s_str tmp = {0};
   str_init_1(&tmp, NULL, p);
   str_to_ident(&tmp, ident);
   return ident;
diff --git a/libkc3/inspect.c b/libkc3/inspect.c
index d446e08..d714bb6 100644
--- a/libkc3/inspect.c
+++ b/libkc3/inspect.c
@@ -18,7 +18,7 @@
 s_str * inspect_sym (const s_sym *sym, s_str *dest)
 {
   sw size;
-  s_buf tmp;
+  s_buf tmp = {0};
   size = buf_inspect_sym_size(&sym);
   if (size < 0) {
     assert(! "error");
diff --git a/libkc3/kc3.c b/libkc3/kc3.c
index a8beb90..9eabf09 100644
--- a/libkc3/kc3.c
+++ b/libkc3/kc3.c
@@ -104,7 +104,7 @@ s_tag * kc3_defoperator (const s_sym **name, const s_sym **sym,
 
 s_tag * kc3_defstruct (const s_list * const *spec, s_tag *dest)
 {
-  s_tag tmp;
+  s_tag tmp = {0};
   assert(spec);
   if (! spec)
     return NULL;
@@ -174,7 +174,7 @@ s_tag * kc3_if_then_else (const s_tag *cond, const s_tag *then,
                           const s_tag *else_, s_tag *dest)
 {
   bool b;
-  s_tag tmp;
+  s_tag tmp = {0};
   const s_sym *type;
   if (! env_eval_tag(&g_kc3_env, cond, &tmp))
     return NULL;