Add 'FUNC_ATTR_NONNULL_RET' to nonnull alloc funcs (#14559)

src/nvim/channel.c

@@ -162,6 +162,7 @@ void channel_init(void)
 /// Channel is allocated with refcount 1, which should be decreased
 /// when the underlying stream closes.
 Channel *channel_alloc(ChannelStreamType type)
+  FUNC_ATTR_NONNULL_RET
 {
   Channel *chan = xcalloc(1, sizeof(*chan));
   if (type == kChannelStreamStdio) {

src/nvim/eval/funcs.c

@@ -2770,11 +2770,10 @@ static void f_get(typval_T *argvars, typval_T *rettv, FunPtr fptr)
         }
       } else if (strcmp(what, "args") == 0) {
         rettv->v_type = VAR_LIST;
-        if (tv_list_alloc_ret(rettv, pt->pt_argc) != NULL) {
+        tv_list_alloc_ret(rettv, pt->pt_argc);
         for (int i = 0; i < pt->pt_argc; i++) {
           tv_list_append_tv(rettv->vval.v_list, &pt->pt_argv[i]);
         }
-        }
       } else {
         EMSG2(_(e_invarg2), what);
       }

src/nvim/eval/typval.c

@@ -2098,7 +2098,7 @@ void tv_dict_set_keys_readonly(dict_T *const dict)
 ///
 /// @return [allocated] pointer to the created list.
 list_T *tv_list_alloc_ret(typval_T *const ret_tv, const ptrdiff_t len)
-  FUNC_ATTR_NONNULL_ALL
+  FUNC_ATTR_NONNULL_ALL FUNC_ATTR_NONNULL_RET
 {
   list_T *const l = tv_list_alloc(len);
   tv_list_set_ret(ret_tv, l);
@@ -2107,6 +2107,7 @@ list_T *tv_list_alloc_ret(typval_T *const ret_tv, const ptrdiff_t len)
 }
 
 dict_T *tv_dict_alloc_lock(VarLockStatus lock)
+  FUNC_ATTR_NONNULL_RET
 {
   dict_T *const d = tv_dict_alloc();
   d->dv_lock = lock;

src/nvim/ex_getln.c

@@ -3571,6 +3571,7 @@ static void save_cmdline(struct cmdline_info *ccp)
  * Restore ccline after it has been saved with save_cmdline().
  */
 static void restore_cmdline(struct cmdline_info *ccp)
+  FUNC_ATTR_NONNULL_ALL
 {
   ccline = *ccp;
 }
@@ -3580,6 +3581,7 @@ static void restore_cmdline(struct cmdline_info *ccp)
  * passed to restore_cmdline_alloc() later.
  */
 char_u *save_cmdline_alloc(void)
+  FUNC_ATTR_NONNULL_RET
 {
   struct cmdline_info *p = xmalloc(sizeof(struct cmdline_info));
   save_cmdline(p);
@@ -3590,6 +3592,7 @@ char_u *save_cmdline_alloc(void)
  * Restore the command line from the return value of save_cmdline_alloc().
  */
 void restore_cmdline_alloc(char_u *p)
+  FUNC_ATTR_NONNULL_ALL
 {
   restore_cmdline((struct cmdline_info *)p);
   xfree(p);

src/nvim/spell.c

@@ -1677,6 +1677,7 @@ static void int_wordlist_spl(char_u *fname)
 // Allocate a new slang_T for language "lang".  "lang" can be NULL.
 // Caller must fill "sl_next".
 slang_T *slang_alloc(char_u *lang)
+  FUNC_ATTR_NONNULL_RET
 {
   slang_T *lp = xcalloc(1, sizeof(slang_T));