diff --git a/src/avatars.c b/src/avatars.c
index 428e62a..21fbceb 100644
--- a/src/avatars.c
+++ b/src/avatars.c
@@ -92,7 +92,7 @@ int avatar_send(Tox *m, uint32_t friendnum)
     }
 
     if (err != TOX_ERR_FILE_SEND_OK) {
-        fprintf(stderr, "tox_file_send failed for friendnumber %d (error %d)\n", friendnum, err);
+        fprintf(stderr, "tox_file_send failed for friendnumber %u (error %d)\n", friendnum, err);
         return -1;
     }
 
diff --git a/src/chat.c b/src/chat.c
index bf9ddca..49f2a07 100644
--- a/src/chat.c
+++ b/src/chat.c
@@ -502,7 +502,7 @@ static void chat_onFileControl(ToxWindow *self, Tox *m, uint32_t friendnum, uint
             /* transfer is accepted */
             if (ft->state == FILE_TRANSFER_PENDING) {
                 ft->state = FILE_TRANSFER_STARTED;
-                line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "File transfer [%d] for '%s' accepted.",
+                line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "File transfer [%zu] for '%s' accepted.",
                               ft->index, ft->file_name);
                 char progline[MAX_STR_SIZE];
                 init_progress_bar(progline);
@@ -660,7 +660,7 @@ static void chat_onFileRecv(ToxWindow *self, Tox *m, uint32_t friendnum, uint32_
         }
     }
 
-    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Type '/savefile %d' to accept the file transfer.", ft->index);
+    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Type '/savefile %zu' to accept the file transfer.", ft->index);
 
     ft->file_size = file_size;
     snprintf(ft->file_path, sizeof(ft->file_path), "%s", file_path);
diff --git a/src/chat_commands.c b/src/chat_commands.c
index 0e857f4..393c46f 100644
--- a/src/chat_commands.c
+++ b/src/chat_commands.c
@@ -103,7 +103,7 @@ void cmd_groupinvite(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*a
         return;
     }
 
-    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Invited contact to Group %d.", groupnum);
+    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Invited contact to Group %lu.", groupnum);
 }
 
 void cmd_join_group(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
@@ -189,7 +189,7 @@ void cmd_savefile(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv
         goto on_recv_error;
     }
 
-    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Saving file [%d] as: '%s'", idx, ft->file_path);
+    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Saving file [%zu] as: '%s'", idx, ft->file_path);
 
     /* prep progress bar line */
     char progline[MAX_STR_SIZE];
diff --git a/src/friendlist.c b/src/friendlist.c
index a7122ae..f3f6352 100644
--- a/src/friendlist.c
+++ b/src/friendlist.c
@@ -407,7 +407,7 @@ static void friendlist_onConnectionChange(ToxWindow *self, Tox *m, uint32_t num,
         ++Friends.num_online;
 
         if (avatar_send(m, num) == -1) {
-            fprintf(stderr, "avatar_send failed for friend %d\n", num);
+            fprintf(stderr, "avatar_send failed for friend %u\n", num);
         }
     }
 
diff --git a/src/line_info.c b/src/line_info.c
index cea57b6..96641cc 100644
--- a/src/line_info.c
+++ b/src/line_info.c
@@ -420,7 +420,7 @@ void line_info_print(ToxWindow *self)
                     }
                 }
 
-                wprintw(win, "\n", line->msg);
+                wprintw(win, "\n");
                 break;
 
             case SYS_MSG:
diff --git a/src/misc_tools.c b/src/misc_tools.c
index 6d756d6..44511f0 100644
--- a/src/misc_tools.c
+++ b/src/misc_tools.c
@@ -553,7 +553,7 @@ void set_window_title(ToxWindow *self, const char *title, int len)
     char cpy[TOXIC_MAX_NAME_LENGTH + 1];
 
     if (self->is_groupchat) { /* keep groupnumber in title */
-        snprintf(cpy, sizeof(cpy), "%d %s", self->num, title);
+        snprintf(cpy, sizeof(cpy), "%u %s", self->num, title);
     } else {
         snprintf(cpy, sizeof(cpy), "%s", title);
     }
diff --git a/src/term_mplex.c b/src/term_mplex.c
index 1420549..0dbe4ee 100644
--- a/src/term_mplex.c
+++ b/src/term_mplex.c
@@ -100,9 +100,19 @@ static char *read_into_dyn_buffer(FILE *stream)
         int length = dyn_buffer_size + strlen(input_ptr);
 
         if (dyn_buffer) {
-            dyn_buffer = (char *) realloc(dyn_buffer, length);
+            char *tmp = realloc(dyn_buffer, length);
+
+            if (tmp == NULL) {
+                return NULL;
+            }
+
+            dyn_buffer = tmp;
         } else {
-            dyn_buffer = (char *) malloc(length);
+            dyn_buffer = malloc(length);
+
+            if (dyn_buffer == NULL) {
+                return NULL;
+            }
         }
 
         strcpy(dyn_buffer + dyn_buffer_size - 1, input_ptr);
diff --git a/src/toxic.c b/src/toxic.c
index 2e5c442..38d732b 100644
--- a/src/toxic.c
+++ b/src/toxic.c
@@ -1106,23 +1106,31 @@ static void parse_args(int argc, char *argv[])
                 break;
 
             case 'f':
+                if (optarg == NULL) {
+                    queue_init_message("Invalid argument for option: %d", opt);
+                    break;
+                }
+
                 arg_opts.use_custom_data = 1;
 
                 if (DATA_FILE) {
                     free(DATA_FILE);
+                    DATA_FILE = NULL;
                 }
 
                 if (BLOCK_FILE) {
                     free(BLOCK_FILE);
+                    BLOCK_FILE = NULL;
                 }
 
                 DATA_FILE = malloc(strlen(optarg) + 1);
-                strcpy(DATA_FILE, optarg);
 
                 if (DATA_FILE == NULL) {
                     exit_toxic_err("failed in parse_args", FATALERR_MEMORY);
                 }
 
+                strcpy(DATA_FILE, optarg);
+
                 BLOCK_FILE = malloc(strlen(optarg) + strlen("-blocklist") + 1);
 
                 if (BLOCK_FILE == NULL) {