diff --git a/README.md b/README.md
index 01651765..fa5dae7f 100644
--- a/README.md
+++ b/README.md
@@ -30,6 +30,7 @@ Current known issues / missing features:
 - The trade window isn't implemented yet.
 - PSO PC and PSOBB are essentially entirely untested. Only GC is fairly well-tested.
 - Add all the chat commands that khyller used to have. (Most, but not all, currently exist in newserv.)
+- The command structures are defined in multiple places. Centralize them.
 
 ## Usage
 
diff --git a/src/LevelTable.hh b/src/LevelTable.hh
index 27eef5f0..bedd1a0a 100644
--- a/src/LevelTable.hh
+++ b/src/LevelTable.hh
@@ -16,7 +16,7 @@ struct LevelStats {
   uint32_t experience; // EXP value of this level
 
   void apply(PlayerStats& ps) const;
-};
+} __attribute__((packed));
 
 // level table format (PlyLevelTbl.prs)
 struct LevelTable {
@@ -28,4 +28,4 @@ struct LevelTable {
 
   const PlayerStats& base_stats_for_class(uint8_t char_class) const;
   const LevelStats& stats_for_level(uint8_t char_class, uint8_t level) const;
-};
+} __attribute__((packed));
diff --git a/src/Map.cc b/src/Map.cc
index efbd363c..85fbbeeb 100644
--- a/src/Map.cc
+++ b/src/Map.cc
@@ -74,7 +74,7 @@ struct EnemyEntry {
   uint32_t reserved14;
   uint32_t skin;
   uint32_t reserved15;
-};
+} __attribute__((packed));
 
 static vector<PSOEnemy> parse_map(uint8_t episode, uint8_t difficulty,
     const BattleParams* battle_params, const EnemyEntry* map,
diff --git a/src/Map.hh b/src/Map.hh
index d14bfeac..4f162c11 100644
--- a/src/Map.hh
+++ b/src/Map.hh
@@ -17,7 +17,7 @@ struct BattleParams {
     uint8_t unknown[14];
     uint32_t experience;
     uint32_t difficulty;
-};
+} __attribute__((packed));
 
 struct BattleParamTable {
   BattleParams entries[2][3][4][0x60]; // online/offline, episode, difficulty, monster type
@@ -28,13 +28,13 @@ struct BattleParamTable {
       uint8_t monster_type) const;
   const BattleParams* get_subtable(bool solo, uint8_t episode,
       uint8_t difficulty) const;
-};
+} __attribute__((packed));
 
 
 
 struct BattleParamIndex {
   BattleParamTable table_for_episode[3];
-};
+} __attribute__((packed));
 
 // an enemy entry as loaded by the game
 struct PSOEnemy {
@@ -46,7 +46,7 @@ struct PSOEnemy {
 
   PSOEnemy();
   PSOEnemy(uint32_t experience, uint32_t rt_index);
-};
+} __attribute__((packed));
 
 std::vector<PSOEnemy> load_map(const char* filename, uint8_t episode,
     uint8_t difficulty, const BattleParams* bp, bool alt_enemies);
diff --git a/src/PSOEncryption.hh b/src/PSOEncryption.hh
index a198ec3a..003d8844 100644
--- a/src/PSOEncryption.hh
+++ b/src/PSOEncryption.hh
@@ -59,7 +59,7 @@ public:
   struct KeyFile {
     uint32_t initial_keys[18];
     uint32_t private_keys[1024];
-  };
+  } __attribute__((packed));
 
   PSOBBEncryption(const KeyFile& key, const void* seed, size_t seed_size);
 
diff --git a/src/Player.hh b/src/Player.hh
index bdc0797f..5820c7f4 100644
--- a/src/Player.hh
+++ b/src/Player.hh
@@ -17,16 +17,16 @@ struct ItemData {
     uint8_t item_data1[12];
     uint16_t item_data1w[6];
     uint32_t item_data1d[3];
-  };
+  } __attribute__((packed));
   uint32_t item_id;
   union {
     uint8_t item_data2[4];
     uint16_t item_data2w[2];
     uint32_t item_data2d;
-  };
+  } __attribute__((packed));
 
   uint32_t primary_identifier() const;
-};
+} __attribute__((packed));
 
 struct PlayerBankItem;
 
@@ -38,7 +38,7 @@ struct PlayerInventoryItem {
   ItemData data;
 
   PlayerBankItem to_bank_item() const;
-};
+} __attribute__((packed));
 
 // an item in a player's bank
 struct PlayerBankItem {
@@ -47,7 +47,7 @@ struct PlayerBankItem {
   uint16_t show_flags;
 
   PlayerInventoryItem to_inventory_item() const;
-};
+} __attribute__((packed));
 
 // a player's inventory (remarkably, the format is the same in all versions of PSO)
 struct PlayerInventory {
@@ -58,7 +58,7 @@ struct PlayerInventory {
   PlayerInventoryItem items[30];
 
   size_t find_item(uint32_t item_id);
-};
+} __attribute__((packed));
 
 // a player's bank
 struct PlayerBank {
@@ -74,7 +74,7 @@ struct PlayerBank {
   void add_item(const PlayerBankItem& item);
   void remove_item(uint32_t item_id, uint32_t amount, PlayerBankItem* item);
   size_t find_item(uint32_t item_id);
-};
+} __attribute__((packed));
 
 
 
@@ -87,7 +87,7 @@ struct PlayerStats {
   uint16_t dfp;
   uint16_t ata;
   uint16_t lck;
-};
+} __attribute__((packed));
 
 struct PlayerDispDataBB;
 
@@ -124,7 +124,7 @@ struct PlayerDispDataPCGC { // 0xD0 in size
   uint8_t technique_levels[0x14];
 
   PlayerDispDataBB to_bb() const;
-};
+} __attribute__((packed));
 
 // BB player preview format
 struct PlayerDispDataBBPreview {
@@ -153,7 +153,7 @@ struct PlayerDispDataBBPreview {
   float proportion_y;
   char16_t name[16];
   uint32_t play_time;
-};
+} __attribute__((packed));
 
 // BB player appearance and stats data
 struct PlayerDispDataBB {
@@ -192,7 +192,7 @@ struct PlayerDispDataBB {
   PlayerDispDataPCGC to_pcgc() const;
   PlayerDispDataBBPreview to_preview() const;
   void apply_preview(const PlayerDispDataBBPreview&);
-};
+} __attribute__((packed));
 
 
 
@@ -205,7 +205,7 @@ struct GuildCardGC {
   uint8_t reserved2; // should be 1
   uint8_t section_id;
   uint8_t char_class;
-};
+} __attribute__((packed));
 
 // BB guild card format
 struct GuildCardBB {
@@ -217,20 +217,20 @@ struct GuildCardBB {
   uint8_t reserved2; // should be 1
   uint8_t section_id;
   uint8_t char_class;
-};
+} __attribute__((packed));
 
 // an entry in the BB guild card file
 struct GuildCardEntryBB {
   GuildCardBB data;
   uint8_t unknown[0xB4];
-};
+} __attribute__((packed));
 
 // the format of the BB guild card file
 struct GuildCardFileBB {
   uint8_t unknown[0x1F84];
   GuildCardEntryBB entry[0x0068]; // that's 104 of them in decimal
   uint8_t unknown2[0x01AC];
-};
+} __attribute__((packed));
 
 // PSOBB key config and team info
 struct KeyAndTeamConfigBB {
@@ -242,10 +242,10 @@ struct KeyAndTeamConfigBB {
   uint32_t team_info[2];           // 02C0
   uint16_t team_privilege_level;   // 02C8
   uint16_t reserved;               // 02CA
-  char16_t team_name[0x0010];       // 02CC
+  char16_t team_name[0x0010];      // 02CC
   uint8_t team_flag[0x0800];       // 02EC
   uint32_t team_rewards[2];        // 0AEC
-};
+} __attribute__((packed));
 
 // BB account data
 struct PlayerAccountDataBB {
@@ -254,7 +254,7 @@ struct PlayerAccountDataBB {
   GuildCardFileBB guild_cards;
   uint32_t options;
   uint8_t shortcuts[0x0A40]; // chat shortcuts (@1FB4 in E7 command)
-};
+} __attribute__((packed));
 
 
 
@@ -264,7 +264,7 @@ struct PlayerLobbyDataPC {
   be_uint32_t ip_address;
   uint32_t client_id;
   char16_t name[16];
-};
+} __attribute__((packed));
 
 struct PlayerLobbyDataGC {
   uint32_t player_tag;
@@ -272,7 +272,7 @@ struct PlayerLobbyDataGC {
   be_uint32_t ip_address;
   uint32_t client_id;
   char name[16];
-};
+} __attribute__((packed));
 
 struct PlayerLobbyDataBB {
   uint32_t player_tag;
@@ -281,14 +281,14 @@ struct PlayerLobbyDataBB {
   uint32_t client_id;
   char16_t name[16];
   uint32_t unknown2;
-};
+} __attribute__((packed));
 
 
 
 struct PSOPlayerDataPC { // for command 0x61
   PlayerInventory inventory;
   PlayerDispDataPCGC disp;
-};
+} __attribute__((packed));
 
 struct PSOPlayerDataGC { // for command 0x61
   PlayerInventory inventory;
@@ -298,7 +298,7 @@ struct PSOPlayerDataGC { // for command 0x61
   uint32_t blocked[0x1E];
   uint32_t auto_reply_enabled;
   char auto_reply[0];
-};
+} __attribute__((packed));
 
 struct PSOPlayerDataBB { // for command 0x61
   PlayerInventory inventory;
@@ -308,19 +308,19 @@ struct PSOPlayerDataBB { // for command 0x61
   uint32_t blocked[0x1E];
   uint32_t auto_reply_enabled;
   char16_t auto_reply[0];
-};
+} __attribute__((packed));
 
 // PC/GC lobby player data (used in lobby/game join commands)
 struct PlayerLobbyJoinDataPCGC {
   PlayerInventory inventory;
   PlayerDispDataPCGC disp;
-};
+} __attribute__((packed));
 
 // BB lobby player data (used in lobby/game join commands)
 struct PlayerLobbyJoinDataBB {
   PlayerInventory inventory;
   PlayerDispDataBB disp;
-};
+} __attribute__((packed));
 
 // complete BB player data format (used in E7 command)
 struct PlayerBB {
@@ -349,7 +349,7 @@ struct PlayerBB {
   uint8_t unknown6[0x002C];         // 2E20 //
   uint8_t quest_data2[0x0058];      // 2E4C // player
   KeyAndTeamConfigBB key_config;    // 2EA4 // account
-};                                  // total size: 39A0
+} __attribute__((packed));          // total size: 39A0
 
 
 
@@ -367,7 +367,7 @@ struct SavedPlayerBB { // .nsc file format
   uint8_t           quest_data1[0x0208];
   uint8_t           quest_data2[0x0058];
   uint8_t           tech_menu_config[0x0028];
-};
+} __attribute__((packed));
 
 struct SavedAccountBB { // .nsa file format
   char signature[0x40];
@@ -378,7 +378,7 @@ struct SavedAccountBB { // .nsa file format
   uint8_t             shortcuts[0x0A40];
   uint8_t             symbol_chats[0x04E0];
   char16_t            team_name[0x0010];
-};
+} __attribute__((packed));
 
 // complete player info stored by the server
 struct Player {
@@ -424,7 +424,7 @@ struct Player {
   void add_item(const PlayerInventoryItem& item);
   void remove_item(uint32_t item_id, uint32_t amount, PlayerInventoryItem* item);
   size_t find_item(uint32_t item_id);
-};
+} __attribute__((packed));
 
 
 
diff --git a/src/Quest.cc b/src/Quest.cc
index 59e13562..7708aeda 100644
--- a/src/Quest.cc
+++ b/src/Quest.cc
@@ -22,7 +22,7 @@ struct PSODownloadQuestHeader {
   be_uint32_t size;
   // Note: use PSO PC encryption, even for GC quests.
   be_uint32_t encryption_seed;
-};
+} __attribute__((packed));
 
 
 
@@ -80,7 +80,7 @@ struct PSOQuestHeaderDC { // same for dc v1 and v2, thankfully
   char name[0x20];
   char short_description[0x80];
   char long_description[0x120];
-};
+} __attribute__((packed));
 
 struct PSOQuestHeaderPC {
   uint32_t start_offset;
@@ -93,7 +93,7 @@ struct PSOQuestHeaderPC {
   char16_t name[0x20];
   char16_t short_description[0x80];
   char16_t long_description[0x120];
-};
+} __attribute__((packed));
 
 struct PSOQuestHeaderGC {
   uint32_t start_offset;
@@ -107,7 +107,7 @@ struct PSOQuestHeaderGC {
   char name[0x20];
   char short_description[0x80];
   char long_description[0x120];
-};
+} __attribute__((packed));
 
 struct PSOQuestHeaderGCEpisode3 {
   // there's actually a lot of other important stuff in here but I'm lazy. it
@@ -119,7 +119,7 @@ struct PSOQuestHeaderGCEpisode3 {
   char location2[0x3C];
   char description[0x190];
   uint8_t unused2[0x3A34];
-};
+} __attribute__((packed));
 
 struct PSOQuestHeaderBB {
   uint32_t start_offset;
@@ -135,7 +135,7 @@ struct PSOQuestHeaderBB {
   char16_t name[0x20];
   char16_t short_description[0x80];
   char16_t long_description[0x120];
-};
+} __attribute__((packed));
 
 
 
@@ -375,7 +375,7 @@ string Quest::decode_gci(const string& filename) {
     uint32_t unknown2;
     uint32_t decompressed_size;
     uint32_t unknown4;
-  };
+  } __attribute__((packed));
   if (compressed_data_with_header.size() < sizeof(DecryptedHeader)) {
     throw runtime_error("GCI file compressed data truncated during header");
   }
diff --git a/src/RareItemSet.hh b/src/RareItemSet.hh
index 4057ddce..62ca43c2 100644
--- a/src/RareItemSet.hh
+++ b/src/RareItemSet.hh
@@ -7,9 +7,10 @@
 struct RareItemDrop {
   uint8_t probability;
   uint8_t item_code[3];
-};
+} __attribute__((packed));
 
 struct RareItemSet {
+  // 0x280 in size; describes one difficulty, section ID, and episode
   RareItemDrop rares[0x65];     // 0000 - 0194 in file
   uint8_t box_areas[0x1E];      // 0194 - 01B2 in file
   RareItemDrop box_rares[0x1E]; // 01B2 - 022A in file
@@ -17,6 +18,6 @@ struct RareItemSet {
 
   RareItemSet(const char* filename, uint8_t episode, uint8_t difficulty,
   	  uint8_t secid);
-}; // 0x280 in size; describes one difficulty, section ID, and episode
+} __attribute__((packed));
 
 bool sample_rare_item(uint8_t pc);
diff --git a/src/ReceiveCommands.cc b/src/ReceiveCommands.cc
index e22901c4..87e59642 100644
--- a/src/ReceiveCommands.cc
+++ b/src/ReceiveCommands.cc
@@ -229,7 +229,7 @@ void process_login_a_dc_pc_gc(shared_ptr<ServerState> s, shared_ptr<Client> c,
     char unused[0x20];
     char serial_number[0x10];
     char access_key[0x10];
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -265,7 +265,7 @@ void process_login_c_dc_pc_gc(shared_ptr<ServerState> s, shared_ptr<Client> c,
     char serial_number[0x30];
     char access_key[0x30];
     char password[0x30];
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -354,7 +354,7 @@ void process_login_bb(shared_ptr<ServerState> s, shared_ptr<Client> c,
     char password[0x10];
     char unused3[0x30];
     ClientConfig cfg;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -436,12 +436,12 @@ void process_ep3_jukebox(shared_ptr<ServerState> s, shared_ptr<Client> c,
     uint32_t transaction_num;
     uint32_t value;
     uint32_t unknown_token;
-  };
+  } __attribute__((packed));
   struct OutputCmd {
     uint32_t remaining_meseta;
     uint32_t unknown;
     uint32_t unknown_token;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(InputCmd));
   const auto* in_cmd = reinterpret_cast<const InputCmd*>(data);
 
@@ -582,7 +582,7 @@ void process_menu_item_info_request(shared_ptr<ServerState> s, shared_ptr<Client
   struct Cmd {
     uint32_t menu_id;
     uint32_t item_id;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd), sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -664,10 +664,10 @@ void process_menu_selection(shared_ptr<ServerState> s, shared_ptr<Client> c,
     uint32_t menu_id;
     uint32_t item_id;
     union {
-      char16_t password_pc_bb[0];
-      char password_dc_gc[0];
-    };
-  };
+      char16_t pc_bb[0];
+      char dc_gc[0];
+    } __attribute__((packed)) password;
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd), sizeof(Cmd) + 0x10 * (1 + uses_unicode));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -796,9 +796,9 @@ void process_menu_selection(shared_ptr<ServerState> s, shared_ptr<Client> c,
         char16_t password[0x10];
         if (size > sizeof(Cmd)) {
           if (uses_unicode) {
-            char16cpy(password, cmd->password_pc_bb, 0x10);
+            char16cpy(password, cmd->password.pc_bb, 0x10);
           } else {
-            decode_sjis(password, cmd->password_dc_gc, 0x10);
+            decode_sjis(password, cmd->password.dc_gc, 0x10);
           }
         }
 
@@ -918,7 +918,7 @@ void process_change_lobby(shared_ptr<ServerState> s, shared_ptr<Client> c,
   struct Cmd {
     uint32_t menu_id;
     uint32_t item_id;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1173,7 +1173,7 @@ void process_chat_pc_bb(shared_ptr<ServerState> s, shared_ptr<Client> c,
   struct Cmd {
     uint32_t unused[2];
     char16_t text[0];
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd), 0xFFFF);
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1185,7 +1185,7 @@ void process_chat_dc_gc(shared_ptr<ServerState> s, shared_ptr<Client> c,
   struct Cmd {
     uint32_t unused[2];
     char text[0];
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd), 0xFFFF);
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1207,7 +1207,7 @@ void process_player_preview_request_bb(shared_ptr<ServerState>, shared_ptr<Clien
   struct Cmd {
     uint32_t player_index;
     uint32_t unused;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1257,7 +1257,7 @@ void process_guild_card_data_request_bb(shared_ptr<ServerState>, shared_ptr<Clie
     uint32_t unknown;
     uint32_t chunk_index;
     uint32_t cont;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1282,7 +1282,7 @@ void process_create_character_bb(shared_ptr<ServerState> s, shared_ptr<Client> c
   struct Cmd {
     uint32_t player_index;
     PlayerDispDataBBPreview preview;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1346,7 +1346,7 @@ void process_change_account_data_bb(shared_ptr<ServerState>, shared_ptr<Client>
     uint8_t pad_config[0x38]; // 05ED
     uint8_t tech_menu[0x28]; // 06ED
     uint8_t customize[0xE8]; // 07ED
-  };
+  } __attribute__((packed));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
   switch (command) {
@@ -1414,7 +1414,7 @@ void process_card_search(shared_ptr<ServerState> s, shared_ptr<Client> c,
     uint32_t player_tag;
     uint32_t searcher_serial_number;
     uint32_t target_serial_number;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1495,7 +1495,7 @@ void process_simple_mail(shared_ptr<ServerState> s, shared_ptr<Client> c,
     char from_name[16];
     uint32_t target_serial_number;
     char data[0x200]; // on GC this appears to contain uninitialized memory!
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1724,7 +1724,7 @@ void process_create_game_pc(shared_ptr<ServerState> s, shared_ptr<Client> c,
     uint8_t battle_mode;
     uint8_t challenge_mode;
     uint8_t unused2;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1746,7 +1746,7 @@ void process_create_game_dc_gc(shared_ptr<ServerState> s, shared_ptr<Client> c,
     uint8_t battle_mode;
     uint8_t challenge_mode;
     uint8_t episode;
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1787,7 +1787,7 @@ void process_create_game_bb(shared_ptr<ServerState> s, shared_ptr<Client> c,
     uint8_t episode;
     uint8_t solo_mode;
     uint8_t unused2[3];
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
@@ -1859,7 +1859,7 @@ void process_login_patch(shared_ptr<ServerState> s, shared_ptr<Client> c,
     uint32_t unused[3];
     char username[0x10];
     char password[0x10];
-  };
+  } __attribute__((packed));
   check_size(size, sizeof(Cmd));
   const auto* cmd = reinterpret_cast<const Cmd*>(data);
 
diff --git a/src/ReceiveSubcommands.cc b/src/ReceiveSubcommands.cc
index 37f893b3..825ee0f0 100644
--- a/src/ReceiveSubcommands.cc
+++ b/src/ReceiveSubcommands.cc
@@ -27,7 +27,7 @@ struct ItemSubcommand {
   uint8_t unused;
   uint32_t item_id;
   uint32_t amount;
-};
+} __attribute__((packed));
 
 
 
@@ -221,7 +221,7 @@ static void process_subcommand_drop_item(shared_ptr<ServerState>,
       float x;
       float y;
       float z;
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if ((cmd->size != 6) || (cmd->client_id != c->lobby_client_id)) {
@@ -253,7 +253,7 @@ static void process_subcommand_drop_stacked_item(shared_ptr<ServerState>,
       float y;
       uint32_t item_id;
       uint32_t amount;
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if (!l->is_game() || (cmd->size != 6) || (cmd->client_id != c->lobby_client_id)) {
@@ -293,7 +293,7 @@ static void process_subcommand_pick_up_item(shared_ptr<ServerState>,
       uint32_t item_id;
       uint8_t area;
       uint8_t unused2[3];
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if (!l->is_game() || (cmd->size != 3) || (cmd->client_id != c->lobby_client_id)) {
@@ -417,7 +417,7 @@ static void process_subcommand_bank_action(shared_ptr<ServerState>,
       uint8_t action;
       uint8_t item_amount;
       uint16_t unused2;
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if (!l->is_game() || (cmd->size != 4)) {
@@ -474,7 +474,7 @@ static void process_subcommand_sort_inventory(shared_ptr<ServerState>,
       uint8_t size;
       uint16_t unused;
       uint32_t item_ids[30];
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if (cmd->size != 31) {
@@ -521,7 +521,7 @@ static void process_subcommand_enemy_drop_item(shared_ptr<ServerState> s,
       float x;
       float y;
       uint32_t unknown[2];
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if ((cmd->size != 6) || !l->is_game()) {
@@ -586,7 +586,7 @@ static void process_subcommand_box_drop_item(shared_ptr<ServerState> s,
       float x;
       float y;
       uint32_t unknown[6];
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if ((cmd->size != 10) || !l->is_game()) {
@@ -655,7 +655,7 @@ static void process_subcommand_monster_hit(shared_ptr<ServerState>,
       uint16_t enemy_id;
       uint16_t damage;
       uint32_t flags;
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if (cmd->size != 10) {
@@ -694,7 +694,7 @@ static void process_subcommand_monster_killed(shared_ptr<ServerState> s,
       uint16_t enemy_id;
       uint16_t killer_client_id;
       uint32_t unused;
-    };
+    } __attribute__((packed));
     auto* cmd = reinterpret_cast<const Cmd*>(p);
 
     if (!l->is_game() || (cmd->size != 3) || (cmd->enemy_id >= l->enemies.size() ||
diff --git a/src/SendCommands.cc b/src/SendCommands.cc
index efe6f658..b3df3ac8 100644
--- a/src/SendCommands.cc
+++ b/src/SendCommands.cc
@@ -205,7 +205,7 @@ static void send_server_init_bb(shared_ptr<ServerState> s, shared_ptr<Client> c)
     uint8_t server_key[0x30];
     uint8_t client_key[0x30];
     char after_message[200];
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   memset(&cmd, 0, sizeof(cmd));
   strcpy(cmd.copyright, bb_game_server_copyright);
@@ -227,7 +227,7 @@ static void send_server_init_patch(shared_ptr<Client> c) {
     uint32_t client_key;
     // BB rejects the command if it's not exactly this size, so we can't add the
     // anti-copyright message... lawyers plz be kind kthx
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   uint32_t server_key = random_object<uint32_t>();
   uint32_t client_key = random_object<uint32_t>();
@@ -263,7 +263,7 @@ void send_update_client_config(shared_ptr<Client> c) {
     uint32_t player_tag;
     uint32_t serial_number;
     ClientConfig config;
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     0x00010000,
     c->license->serial_number,
     c->export_config(),
@@ -280,7 +280,7 @@ void send_reconnect(shared_ptr<Client> c, uint32_t address, uint16_t port) {
     be_uint32_t address;
     uint16_t port;
     uint16_t unused;
-  } cmd = {address, port, 0};
+  } __attribute__((packed)) cmd = {address, port, 0};
   send_command(c, 0x19, 0x00, cmd);
 }
 
@@ -298,7 +298,7 @@ void send_pc_gc_split_reconnect(shared_ptr<Client> c, uint32_t address,
     be_uint32_t gc_address;
     uint16_t gc_port;
     uint8_t unused2[0xB0 - 0x23];
-  } cmd;
+  } __attribute__((packed)) cmd;
   memset(&cmd, 0, sizeof(cmd));
   cmd.pc_address = address;
   cmd.pc_port = pc_port;
@@ -321,7 +321,7 @@ void send_client_init_bb(shared_ptr<Client> c, uint32_t error) {
     uint32_t team_id; // just randomize it; teams aren't supported
     ClientConfig cfg;
     uint32_t caps; // should be 0x00000102
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     error,
     0x00010000,
     c->license->serial_number,
@@ -346,14 +346,14 @@ void send_player_preview_bb(shared_ptr<Client> c, uint8_t player_index,
     struct {
       uint32_t player_index;
       uint32_t error;
-    } cmd = {player_index, 0x00000002};
+    } __attribute__((packed)) cmd = {player_index, 0x00000002};
     send_command(c, 0x00E4, 0x00000000, cmd);
 
   } else {
     struct {
       uint32_t player_index;
       PlayerDispDataBBPreview preview;
-    } cmd = {player_index, *preview};
+    } __attribute__((packed)) cmd = {player_index, *preview};
     send_command(c, 0x00E3, 0x00000000, cmd);
   }
 }
@@ -363,7 +363,7 @@ void send_accept_client_checksum_bb(shared_ptr<Client> c) {
   struct {
     uint32_t verify;
     uint32_t unused;
-  } cmd = {1, 0};
+  } __attribute__((packed)) cmd = {1, 0};
   send_command(c, 0x02E8, 0x00000000, cmd);
 }
 
@@ -375,7 +375,7 @@ void send_guild_card_header_bb(shared_ptr<Client> c) {
     uint32_t unknown; // should be 1
     uint32_t filesize; // 0x0000490
     uint32_t checksum;
-  } cmd = {1, 0x490, checksum};
+  } __attribute__((packed)) cmd = {1, 0x490, checksum};
   send_command(c, 0x01DC, 0x00000000, cmd);
 }
 
@@ -407,7 +407,7 @@ void send_stream_file_bb(shared_ptr<Client> c) {
     uint32_t checksum;
     uint32_t offset;
     char filename[0x40];
-  };
+  } __attribute__((packed));
 
   auto index_data = file_cache.get("system/blueburst/streamfile.ind");
   if (index_data->size() % sizeof(StreamFileEntry)) {
@@ -422,7 +422,7 @@ void send_stream_file_bb(shared_ptr<Client> c) {
   struct {
     uint32_t chunk_index;
     uint8_t data[0x6800];
-  } chunk_cmd;
+  } __attribute__((packed)) chunk_cmd;
   chunk_cmd.chunk_index = 0;
 
   uint32_t buffer_offset = 0;
@@ -464,7 +464,7 @@ void send_approve_player_choice_bb(shared_ptr<Client> c) {
   struct {
     uint32_t player_index;
     uint32_t unused;
-  } cmd = {c->bb_player_index, 1};
+  } __attribute__((packed)) cmd = {c->bb_player_index, 1};
   send_command(c, 0x00E4, 0x00000000, cmd);
 }
 
@@ -493,7 +493,7 @@ void send_check_directory_patch(shared_ptr<Client> c, const char* dir) {
 struct LargeMessageOptionalHeader {
   uint32_t unused;
   uint32_t serial_number;
-};
+} __attribute__((packed));
 
 static void send_large_message_pc_patch_bb(shared_ptr<Client> c, uint8_t command,
     const char16_t* text, uint32_t from_serial_number, bool include_header) {
@@ -594,7 +594,7 @@ void send_simple_mail_gc(std::shared_ptr<Client> c, uint32_t from_serial_number,
     char from_name[0x10];
     uint32_t to_serial_number;
     char text[0x200];
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   memset(&cmd, 0, sizeof(cmd));
   cmd.player_tag = 0x00010000;
@@ -624,7 +624,7 @@ static void send_info_board_pc_bb(shared_ptr<Client> c, shared_ptr<Lobby> l) {
   struct Entry {
     char16_t name[0x10];
     char16_t message[0xAC];
-  };
+  } __attribute__((packed));
   vector<Entry> entries;
 
   for (const auto& c : l->clients) {
@@ -647,7 +647,7 @@ static void send_info_board_dc_gc(shared_ptr<Client> c, shared_ptr<Lobby> l) {
   struct Entry {
     char name[0x10];
     char message[0xAC];
-  };
+  } __attribute__((packed));
   vector<Entry> entries;
 
   for (const auto& c : l->clients) {
@@ -693,23 +693,23 @@ static void send_card_search_result_dc_pc_gc(shared_ptr<ServerState> s,
           uint8_t dcgc_command;
           uint8_t dcgc_flag;
           uint16_t dcgc_size;
-        };
+        } __attribute__((packed));
         struct {
           uint16_t pc_size;
           uint8_t pc_command;
           uint8_t pc_flag;
-        };
-      };
+        } __attribute__((packed));
+      } __attribute__((packed));
       uint32_t address;
       uint16_t port;
       uint16_t unused;
-    } destination_command;
+    } __attribute__((packed)) destination_command;
     char location_string[0x44];
     uint32_t menu_id;
     uint32_t lobby_id;
     char unused[0x3C];
     char16_t name[0x20];
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   memset(&cmd, 0, sizeof(cmd));
   cmd.player_tag = 0x00010000;
@@ -766,13 +766,13 @@ static void send_card_search_result_bb(shared_ptr<ServerState> s,
       uint32_t address;
       uint16_t port;
       uint16_t unused;
-    } destination_command;
+    } __attribute__((packed)) destination_command;
     char location_string[0x44];
     uint32_t menu_id;
     uint32_t lobby_id;
     char unused[0x3C];
     char16_t name[0x20];
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   memset(&cmd, 0, sizeof(cmd));
   cmd.player_tag = 0x00010000;
@@ -828,7 +828,7 @@ static void send_guild_card_gc(shared_ptr<Client> c, shared_ptr<Client> source)
     uint8_t reserved2;
     uint8_t section_id;
     uint8_t char_class;
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   cmd.subcommand = 0x06;
   cmd.subsize = 0x25;
@@ -860,7 +860,7 @@ static void send_guild_card_bb(shared_ptr<Client> c, shared_ptr<Client> source)
     uint8_t reserved2;
     uint8_t section_id;
     uint8_t char_class;
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   cmd.subcommand = 0x06;
   cmd.subsize = 0x43;
@@ -902,7 +902,7 @@ static void send_menu_pc_bb(shared_ptr<Client> c, const char16_t* menu_name,
     uint32_t item_id;
     uint16_t flags; // should be 0x0F04
     char16_t text[17];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   entries.emplace_back();
@@ -944,7 +944,7 @@ static void send_menu_dc_gc(shared_ptr<Client> c, const char16_t* menu_name,
     uint32_t item_id;
     uint16_t flags; // should be 0x0F04
     char text[18];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   entries.emplace_back();
@@ -1004,7 +1004,7 @@ static void send_game_menu_pc(shared_ptr<Client> c, shared_ptr<ServerState> s) {
     char16_t name[0x10];
     uint8_t episode;
     uint8_t flags;
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   {
@@ -1046,7 +1046,7 @@ static void send_game_menu_gc(shared_ptr<Client> c, shared_ptr<ServerState> s) {
     char name[0x10];
     uint8_t episode;
     uint8_t flags;
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   {
@@ -1093,7 +1093,7 @@ static void send_game_menu_bb(shared_ptr<Client> c, shared_ptr<ServerState> s) {
     char16_t name[0x10];
     uint8_t episode;
     uint8_t flags;
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   {
@@ -1151,7 +1151,7 @@ static void send_quest_menu_pc(shared_ptr<Client> c, uint32_t menu_id,
     uint32_t quest_id;
     char16_t name[0x20];
     char16_t short_desc[0x70];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   for (const auto& quest : quests) {
@@ -1174,7 +1174,7 @@ static void send_quest_menu_pc(std::shared_ptr<Client> c, uint32_t menu_id,
     uint32_t item_id;
     char16_t name[0x20];
     char16_t short_desc[0x70];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   for (const auto& item : items) {
@@ -1197,7 +1197,7 @@ static void send_quest_menu_gc(shared_ptr<Client> c, uint32_t menu_id,
     uint32_t quest_id;
     char name[0x20];
     char short_desc[0x70];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   for (const auto& quest : quests) {
@@ -1220,7 +1220,7 @@ static void send_quest_menu_gc(shared_ptr<Client> c, uint32_t menu_id,
     uint32_t item_id;
     char name[0x20];
     char short_desc[0x70];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   for (const auto& item : items) {
@@ -1245,7 +1245,7 @@ static void send_quest_menu_bb(shared_ptr<Client> c, uint32_t menu_id,
     uint32_t quest_id;
     char16_t name[0x20];
     char16_t short_desc[0x7A];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   for (const auto& quest : quests) {
@@ -1270,7 +1270,7 @@ static void send_quest_menu_bb(shared_ptr<Client> c, uint32_t menu_id,
     uint32_t item_id;
     char16_t name[0x20];
     char16_t short_desc[0x7A];
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   for (const auto& item : items) {
@@ -1321,7 +1321,7 @@ void send_lobby_list(shared_ptr<Client> c, shared_ptr<ServerState> s) {
     uint32_t menu_id;
     uint32_t item_id;
     uint32_t unused; // should be 0x00000000
-  };
+  } __attribute__((packed));
 
   vector<Entry> entries;
   for (shared_ptr<Lobby> l : s->all_lobbies()) {
@@ -1364,7 +1364,7 @@ static void send_join_game_pc(shared_ptr<Client> c, shared_ptr<Lobby> l) {
     uint8_t unused2;
     uint8_t solo_mode;
     uint8_t unused3;
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   size_t player_count = 0;
   memcpy(cmd.variations, l->variations, sizeof(cmd.variations));
@@ -1458,7 +1458,7 @@ static void send_join_game_bb(shared_ptr<Client> c, shared_ptr<Lobby> l) {
     uint8_t unused2;
     uint8_t solo_mode;
     uint8_t unused3;
-  } cmd;
+  } __attribute__((packed)) cmd;
 
   size_t player_count = 0;
   memcpy(cmd.variations, l->variations, sizeof(cmd.variations));
@@ -1500,7 +1500,7 @@ static void send_join_lobby_pc(shared_ptr<Client> c, shared_ptr<Lobby> l) {
     uint16_t block_number;
     uint16_t event;
     uint32_t unused;
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     c->lobby_client_id,
     l->leader_id,
     0x01,
@@ -1513,7 +1513,7 @@ static void send_join_lobby_pc(shared_ptr<Client> c, shared_ptr<Lobby> l) {
   struct Entry {
     PlayerLobbyDataPC lobby_data;
     PlayerLobbyJoinDataPCGC data;
-  };
+  } __attribute__((packed));
   vector<Entry> entries;
 
   for (size_t x = 0; x < l->max_clients; x++) {
@@ -1557,7 +1557,7 @@ static void send_join_lobby_gc(shared_ptr<Client> c, shared_ptr<Lobby> l) {
     uint16_t block_number;
     uint16_t event;
     uint32_t unused;
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     c->lobby_client_id,
     l->leader_id,
     0x01,
@@ -1570,7 +1570,7 @@ static void send_join_lobby_gc(shared_ptr<Client> c, shared_ptr<Lobby> l) {
   struct Entry {
     PlayerLobbyDataGC lobby_data;
     PlayerLobbyJoinDataPCGC data;
-  };
+  } __attribute__((packed));
   vector<Entry> entries;
 
   for (size_t x = 0; x < l->max_clients; x++) {
@@ -1606,7 +1606,7 @@ static void send_join_lobby_bb(shared_ptr<Client> c, shared_ptr<Lobby> l) {
     uint16_t block_number;
     uint16_t event;
     uint32_t unused;
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     c->lobby_client_id,
     l->leader_id,
     0x01,
@@ -1619,7 +1619,7 @@ static void send_join_lobby_bb(shared_ptr<Client> c, shared_ptr<Lobby> l) {
   struct Entry {
     PlayerLobbyDataBB lobby_data;
     PlayerLobbyJoinDataBB data;
-  };
+  } __attribute__((packed));
   vector<Entry> entries;
 
   for (size_t x = 0; x < l->max_clients; x++) {
@@ -1693,7 +1693,7 @@ static void send_player_join_notification_pc(shared_ptr<Client> c,
     uint32_t unused;
     PlayerLobbyDataPC lobby_data;
     PlayerLobbyJoinDataPCGC data;
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     0xFF,
     l->leader_id,
     0x01,
@@ -1722,7 +1722,7 @@ static void send_player_join_notification_gc(shared_ptr<Client> c,
     uint32_t unused;
     PlayerLobbyDataGC lobby_data;
     PlayerLobbyJoinDataPCGC data;
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     0xFF,
     l->leader_id,
     0x01,
@@ -1751,7 +1751,7 @@ static void send_player_join_notification_bb(shared_ptr<Client> c,
     uint32_t unused;
     PlayerLobbyDataBB lobby_data;
     PlayerLobbyJoinDataBB data;
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     0xFF,
     l->leader_id,
     0x01,
@@ -1789,7 +1789,7 @@ void send_player_leave_notification(shared_ptr<Lobby> l, uint8_t leaving_client_
     uint8_t client_id;
     uint8_t leader_id;
     uint16_t unused;
-  } cmd = {leaving_client_id, l->leader_id, 0};
+  } __attribute__((packed)) cmd = {leaving_client_id, l->leader_id, 0};
   send_command(l, l->is_game() ? 0x66 : 0x69, leaving_client_id, cmd);
 }
 
@@ -1807,7 +1807,7 @@ void send_arrow_update(shared_ptr<Lobby> l) {
     uint32_t player_tag;
     uint32_t serial_number;
     uint32_t arrow_color;
-  };
+  } __attribute__((packed));
   vector<Entry> entries;
 
   for (size_t x = 0; x < l->max_clients; x++) {
@@ -1926,7 +1926,7 @@ void send_drop_item(shared_ptr<Lobby> l, const ItemData& item,
     float y;
     uint32_t unused2;
     ItemData data;
-  } cmd = {0x5F, 0x0A, 0x0000, area, from_enemy, request_id, x, y, 0, item};
+  } __attribute__((packed)) cmd = {0x5F, 0x0A, 0x0000, area, from_enemy, request_id, x, y, 0, item};
   send_command(l, 0x60, 0x00, cmd);
 }
 
@@ -1943,7 +1943,7 @@ void send_drop_stacked_item(shared_ptr<Lobby> l, const ItemData& item,
     float y;
     uint32_t unused3;
     ItemData data;
-  } cmd = {0x5D, 0x09, 0x0000, area, 0, x, y, 0, item};
+  } __attribute__((packed)) cmd = {0x5D, 0x09, 0x0000, area, 0, x, y, 0, item};
   send_command(l, 0x60, 0x00, cmd);
 }
 
@@ -1957,7 +1957,7 @@ void send_pick_up_item(shared_ptr<Lobby> l, shared_ptr<Client> c,
     uint16_t client_id2;
     uint16_t area;
     uint32_t item_id;
-  } cmd = {0x59, 0x03, c->lobby_client_id, c->lobby_client_id, area, item_id};
+  } __attribute__((packed)) cmd = {0x59, 0x03, c->lobby_client_id, c->lobby_client_id, area, item_id};
   send_command(l, 0x60, 0x00, cmd);
 }
 
@@ -1970,7 +1970,7 @@ void send_create_inventory_item(shared_ptr<Lobby> l, shared_ptr<Client> c,
     uint16_t client_id;
     ItemData item;
     uint32_t unused;
-  } cmd = {0xBE, 0x07, c->lobby_client_id, item, 0};
+  } __attribute__((packed)) cmd = {0xBE, 0x07, c->lobby_client_id, item, 0};
   send_command(l, 0x60, 0x00, cmd);
 }
 
@@ -1983,7 +1983,7 @@ void send_destroy_item(shared_ptr<Lobby> l, shared_ptr<Client> c,
     uint16_t client_id;
     uint32_t item_id;
     uint32_t amount;
-  } cmd = {0x29, 0x03, c->lobby_client_id, item_id, amount};
+  } __attribute__((packed)) cmd = {0x29, 0x03, c->lobby_client_id, item_id, amount};
   send_command(l, 0x60, 0x00, cmd);
 }
 
@@ -2001,7 +2001,7 @@ void send_bank(shared_ptr<Client> c) {
     uint32_t checksum; // can be random; client won't notice
     uint32_t numItems;
     uint32_t meseta;
-  } cmd = {0xBC, 0, 0, 0, checksum, c->player.bank.num_items, c->player.bank.meseta};
+  } __attribute__((packed)) cmd = {0xBC, 0, 0, 0, checksum, c->player.bank.num_items, c->player.bank.meseta};
 
   size_t size = 8 + sizeof(cmd) + items.size() * sizeof(PlayerBankItem);
   cmd.size = size;
@@ -2019,7 +2019,7 @@ void send_shop(shared_ptr<Client> c, uint8_t shop_type) {
     uint8_t num_items;
     uint16_t unused;
     ItemData entries[20];
-  } cmd = {
+  } __attribute__((packed)) cmd = {
     0xB6,
     0x2C,
     0x037F,
@@ -2104,7 +2104,7 @@ void send_ep3_rank_update(shared_ptr<Client> c) {
     uint32_t meseta;
     uint32_t max_meseta;
     uint32_t jukebox_songs_unlocked;
-  } cmd = {0, "\0\0\0\0\0\0\0\0\0\0\0", 0x00FFFFFF, 0x00FFFFFF, 0xFFFFFFFF};
+  } __attribute__((packed)) cmd = {0, "\0\0\0\0\0\0\0\0\0\0\0", 0x00FFFFFF, 0x00FFFFFF, 0xFFFFFFFF};
   send_command(c, 0xB7, 0x00, cmd);
 }
 
@@ -2140,10 +2140,6 @@ void send_ep3_map_data(shared_ptr<Lobby> l, uint32_t map_id) {
 
 
 
-////////////////////////////////////////////////////////////////////////////////
-// CommandLoadQuestFile: sends a quest file to the client.
-// the _OpenFile functions send the begin command (44/A6), and the _SendChunk functions send a chunk of data (13/A7).
-
 static void send_quest_open_file_pc_gc(shared_ptr<Client> c,
     const string& filename, uint32_t file_size, bool is_download_quest,
     bool is_ep3_quest) {
@@ -2153,7 +2149,7 @@ static void send_quest_open_file_pc_gc(shared_ptr<Client> c,
     uint16_t flags;
     char filename[0x10];
     uint32_t file_size;
-  } cmd;
+  } __attribute__((packed)) cmd;
   memset(&cmd, 0, sizeof(cmd));
   strncpy(cmd.name, filename.c_str(), 0x1F);
   cmd.flags = 2 + is_ep3_quest;
@@ -2171,7 +2167,7 @@ static void send_quest_open_file_bb(shared_ptr<Client> c,
     char filename[0x10];
     uint32_t file_size;
     char name[0x18];
-  } cmd;
+  } __attribute__((packed)) cmd;
   memset(&cmd, 0, sizeof(cmd));
   cmd.flags = 2 + is_ep3_quest;
   strncpy(cmd.filename, filename.c_str(), 0x0F);
@@ -2189,7 +2185,7 @@ static void send_quest_file_chunk(shared_ptr<Client> c, const char* filename,
     char filename[0x10];
     uint8_t data[0x400];
     uint32_t data_size;
-  } cmd;
+  } __attribute__((packed)) cmd;
   memset(cmd.filename, 0, 0x10);
   strncpy(cmd.filename, filename, 0x0F);
   memcpy(cmd.data, data, size);
diff --git a/src/SendCommands.hh b/src/SendCommands.hh
index a9859af0..ef699fb7 100644
--- a/src/SendCommands.hh
+++ b/src/SendCommands.hh
@@ -147,7 +147,7 @@ struct JoinGameCommand_GC_64 {
   struct {
     PlayerInventory inventory;
     PlayerDispDataPCGC disp;
-  } player[4]; // only used on ep3
+  } __attribute__((packed)) player[4]; // only used on ep3
 } __attribute__((packed));
 
 void send_join_lobby(std::shared_ptr<Client> c, std::shared_ptr<Lobby> l);