diff --git a/src/bodygraph.cpp b/src/bodygraph.cpp
index 5afe1a53af2e4..a696785b0759d 100644
--- a/src/bodygraph.cpp
+++ b/src/bodygraph.cpp
@@ -386,7 +386,7 @@ void bodygraph_display::draw_partlist()
     werase( w_partlist );
     int y = 0;
     for( int i = top_part; y < all_height - 2 && i < static_cast<int>( partlist.size() ); i++ ) {
-        const auto bgt = partlist[i];
+        const auto &bgt = partlist[i];
         std::string txt = !std::get<1>( bgt ) ?
                           std::get<0>( bgt )->name.translated() :
                           std::get<1>( bgt )->name.translated();
diff --git a/src/character.cpp b/src/character.cpp
index 51d68f0b5a918..81529b3e238e1 100644
--- a/src/character.cpp
+++ b/src/character.cpp
@@ -9799,7 +9799,7 @@ Character::moncam_cache_t Character::get_active_moncams() const
 {
     moncam_cache_t ret;
     for( monster const &mon : g->all_monsters() ) {
-        for( std::pair<mtype_id, int> const moncam : get_moncams() ) {
+        for( const std::pair<const mtype_id, int> &moncam : get_moncams() ) {
             if( mon.type->id == moncam.first && mon.friendly != 0 &&
                 rl_dist( get_avatar().get_location(), mon.get_location() ) < moncam.second ) {
                 ret.insert( { &mon, mon.get_location() } );
diff --git a/src/game.cpp b/src/game.cpp
index 01192b1e1c59f..ac8511cd87e33 100644
--- a/src/game.cpp
+++ b/src/game.cpp
@@ -1723,7 +1723,7 @@ units::temperature_delta get_convection_temperature( const tripoint &location )
                                         units::from_fahrenheit_delta( fd_fire->get_intensity_level().convection_temperature_mod ) :
                                         units::from_kelvin_delta( 0 );
     // Modifier from fields
-    for( auto fd : here.field_at( location ) ) {
+    for( auto &fd : here.field_at( location ) ) {
         // Nullify lava modifier when there is open fire
         if( fd.first.obj().has_fire ) {
             lava_mod = units::from_kelvin_delta( 0 );
@@ -1955,7 +1955,7 @@ static hint_rating rate_action_eat( const avatar &you, const item &it )
                 if( rate.success() ) {
                     best_rate = hint_rating::good;
                     return VisitResponse::ABORT;
-                } else if( rate.value() != INEDIBLE || rate.value() != INEDIBLE_MUTATION ) {
+                } else if( rate.value() != INEDIBLE && rate.value() != INEDIBLE_MUTATION ) {
                     best_rate = hint_rating::iffy;
                 }
             }
diff --git a/src/iexamine.cpp b/src/iexamine.cpp
index 7c4a79bf7eec2..e94fe18e7a850 100644
--- a/src/iexamine.cpp
+++ b/src/iexamine.cpp
@@ -6164,7 +6164,7 @@ static void mill_activate( Character &you, const tripoint_bub_ms &examp )
         }
     }
 
-    for( std::pair<const string_id<itype>, int> mill_type_count : millable_counts ) {
+    for( const std::pair<const string_id<itype>, int> &mill_type_count : millable_counts ) {
         item source( mill_type_count.first );
         const item product( source.type->milling_data->into_ );
         const recipe rec = *source.type->milling_data->recipe_;
diff --git a/src/item.cpp b/src/item.cpp
index ed36efdf96b81..6b5eb7bd8bf9f 100644
--- a/src/item.cpp
+++ b/src/item.cpp
@@ -8963,7 +8963,7 @@ int item::chip_resistance( bool worst, const bodypart_id &bp ) const
     }
 
     const int total = type->mat_portion_total == 0 ? 1 : type->mat_portion_total;
-    for( const std::pair<material_id, int> mat : made_of() ) {
+    for( const std::pair<const material_id, int> &mat : made_of() ) {
         const int val = ( mat.first->chip_resist() * mat.second ) / total;
         res = worst ? std::min( res, val ) : std::max( res, val );
     }
@@ -10464,7 +10464,7 @@ const material_type &item::get_random_material() const
     std::vector<material_id> matlist;
     const std::map<material_id, int> &mats = made_of();
     matlist.reserve( mats.size() );
-    for( auto mat : mats ) {
+    for( const std::pair<const material_id, int> &mat : mats ) {
         matlist.emplace_back( mat.first );
     }
     return *random_entry( matlist, material_id::NULL_ID() );
@@ -10475,7 +10475,7 @@ const material_type &item::get_base_material() const
     const std::map<material_id, int> &mats = made_of();
     const material_type *m = &material_id::NULL_ID().obj();
     int portion = 0;
-    for( const std::pair<material_id, int> mat : mats ) {
+    for( const std::pair<const material_id, int> &mat : mats ) {
         if( mat.second > portion ) {
             portion = mat.second;
             m = &mat.first.obj();
@@ -12070,7 +12070,7 @@ bool item::flammable( int threshold ) const
 
     int flammability = 0;
     units::volume volume_per_turn = 0_ml;
-    for( const std::pair<material_id, int> m : mats ) {
+    for( const std::pair<const material_id, int> &m : mats ) {
         const mat_burn_data &bd = m.first->burn_data( 1 );
         if( bd.immune ) {
             // Made to protect from fire
diff --git a/src/iuse_actor.cpp b/src/iuse_actor.cpp
index 5a996d5f2060b..aa300e3a11693 100644
--- a/src/iuse_actor.cpp
+++ b/src/iuse_actor.cpp
@@ -1659,7 +1659,7 @@ void salvage_actor::cut_up( Character &p, item_location &cut ) const
     std::map<itype_id, int> salvage;
     std::map<material_id, units::mass> mat_to_weight;
     std::set<material_id> mat_set;
-    for( std::pair<material_id, int> mat : cut.get_item()->made_of() ) {
+    for( const std::pair<const material_id, int> &mat : cut.get_item()->made_of() ) {
         mat_set.insert( mat.first );
     }
 
diff --git a/src/magic_enchantment.cpp b/src/magic_enchantment.cpp
index f6e9ddb67cfdd..f7ac8a99688c7 100644
--- a/src/magic_enchantment.cpp
+++ b/src/magic_enchantment.cpp
@@ -1130,7 +1130,7 @@ void enchant_cache::activate_passive( Character &guy ) const
     if( emitter ) {
         get_map().emit_field( guy.pos_bub(), *emitter );
     }
-    for( const std::pair<efftype_id, int> eff : ench_effects ) {
+    for( const std::pair<const efftype_id, int> &eff : ench_effects ) {
         guy.add_effect( eff.first, 1_seconds, false, eff.second );
     }
     for( const std::pair<const time_duration, std::vector<fake_spell>> &activation :
diff --git a/src/math_parser_diag.cpp b/src/math_parser_diag.cpp
index 7824b50e74272..b4af37792b643 100644
--- a/src/math_parser_diag.cpp
+++ b/src/math_parser_diag.cpp
@@ -272,7 +272,7 @@ diag_eval_dbl_f faction_food_supply_eval( char /* scope */,
 {
     return [fac_val = params[0]]( const_dialogue const & d ) {
         faction *fac = g->faction_manager_ptr->get( faction_id( fac_val.str( d ) ) );
-        return fac->food_supply.calories;
+        return static_cast<double>( fac->food_supply.calories );
     };
 }
 
diff --git a/src/mutation.cpp b/src/mutation.cpp
index 5429cbd7a6080..1b9440d239f51 100644
--- a/src/mutation.cpp
+++ b/src/mutation.cpp
@@ -640,7 +640,7 @@ void Character::mutation_effect( const trait_id &mut, const bool worn_destroyed_
         return true;
     } );
 
-    for( std::pair<mtype_id, int> moncam : branch.moncams ) {
+    for( const std::pair<const mtype_id, int> &moncam : branch.moncams ) {
         add_moncam( moncam );
     }
 
@@ -674,7 +674,7 @@ void Character::mutation_loss_effect( const trait_id &mut )
         recalculate_bodyparts();
     }
 
-    for( std::pair<mtype_id, int> moncam : branch.moncams ) {
+    for( const std::pair<const mtype_id, int> &moncam : branch.moncams ) {
         remove_moncam( moncam.first );
     }
 
diff --git a/src/mutation_data.cpp b/src/mutation_data.cpp
index b634a513fb014..daf6055867aab 100644
--- a/src/mutation_data.cpp
+++ b/src/mutation_data.cpp
@@ -679,7 +679,7 @@ void mutation_branch::check_consistency()
                 debugmsg( "mutation %s transform uses undefined target %s", mid.c_str(), tid.c_str() );
             }
         }
-        for( const std::pair<species_id, int> elem : an_id ) {
+        for( const std::pair<const species_id, int> &elem : an_id ) {
             if( !elem.first.is_valid() ) {
                 debugmsg( "mutation %s refers to undefined species id %s", mid.c_str(), elem.first.c_str() );
             }
diff --git a/src/newcharacter.cpp b/src/newcharacter.cpp
index 7a4d1b9ec8d8f..053bb937fec7c 100644
--- a/src/newcharacter.cpp
+++ b/src/newcharacter.cpp
@@ -2376,7 +2376,7 @@ static std::string assemble_profession_details( const avatar &u, const input_con
     // Profession spells
     if( !sorted_profs[cur_id]->spells().empty() ) {
         assembled += "\n" + colorize( _( "Profession spells:" ), COL_HEADER ) + "\n";
-        for( const std::pair<spell_id, int> spell_pair : sorted_profs[cur_id]->spells() ) {
+        for( const std::pair<const spell_id, int> &spell_pair : sorted_profs[cur_id]->spells() ) {
             assembled += string_format( _( "%s level %d" ), spell_pair.first->name, spell_pair.second ) + "\n";
         }
     }
@@ -2784,7 +2784,7 @@ static std::string assemble_hobby_details( const avatar &u, const input_context
     // Background spells
     if( !sorted_hobbies[cur_id]->spells().empty() ) {
         assembled += "\n" + colorize( _( "Background spells:" ), COL_HEADER ) + "\n";
-        for( const std::pair<spell_id, int> spell_pair : sorted_hobbies[cur_id]->spells() ) {
+        for( const std::pair<const spell_id, int> &spell_pair : sorted_hobbies[cur_id]->spells() ) {
             assembled += string_format( _( "%s level %d" ), spell_pair.first->name, spell_pair.second ) + "\n";
         }
     }
diff --git a/src/npc.cpp b/src/npc.cpp
index 319ea72afdb99..b5d517cda2c9d 100644
--- a/src/npc.cpp
+++ b/src/npc.cpp
@@ -703,7 +703,7 @@ void npc::randomize( const npc_class_id &type, const npc_template_id &tem_id )
     // Add martial arts
     learn_ma_styles_from_traits();
     // Add spells for magiclysm mod
-    for( std::pair<spell_id, int> spell_pair : myclass->_starting_spells ) {
+    for( const std::pair<const spell_id, int> &spell_pair : myclass->_starting_spells ) {
         this->magic->learn_spell( spell_pair.first, *this, true );
         spell &sp = this->magic->get_spell( spell_pair.first );
         while( sp.get_level() < spell_pair.second && !sp.is_max_level( *this ) ) {
diff --git a/src/overmap.cpp b/src/overmap.cpp
index 84e7ace4fab89..b240d54a13cc9 100644
--- a/src/overmap.cpp
+++ b/src/overmap.cpp
@@ -2404,7 +2404,7 @@ struct mutable_overmap_phase_remainder {
     ) const {
         int context_mandatory_joins_shortfall = 0;
 
-        for( const mutable_overmap_piece_candidate piece : rule.pieces( origin, dir ) ) {
+        for( const mutable_overmap_piece_candidate &piece : rule.pieces( origin, dir ) ) {
             if( !overmap::inbounds( piece.pos ) ) {
                 return std::nullopt;
             }
@@ -2421,7 +2421,7 @@ struct mutable_overmap_phase_remainder {
 
         std::vector<om_pos_dir> suppressed_joins;
 
-        for( const std::pair<om_pos_dir, const mutable_overmap_terrain_join *> p :
+        for( const std::pair<om_pos_dir, const mutable_overmap_terrain_join *> &p :
              rule.outward_joins( origin, dir ) ) {
             const om_pos_dir &pos_d = p.first;
             const mutable_overmap_terrain_join &ter_join = *p.second;
@@ -2800,7 +2800,7 @@ struct mutable_overmap_special_data : overmap_special_data {
             if( rule ) {
                 const tripoint_om_omt &satisfy_origin = satisfy_result.origin;
                 om_direction::type rot = satisfy_result.dir;
-                for( const mutable_overmap_piece_candidate piece : rule->pieces( satisfy_origin, rot ) ) {
+                for( const mutable_overmap_piece_candidate &piece : rule->pieces( satisfy_origin, rot ) ) {
                     const mutable_overmap_terrain &ter = *piece.overmap;
                     add_ter( ter, piece.pos, piece.rot, satisfy_result.suppressed_joins );
                 }
@@ -6620,7 +6620,7 @@ void overmap::connect_closest_points( const std::vector<point_om_omt> &points, i
     // track which subgraph each point belongs to
     std::vector<int> subgraphs( points.size(), -1 );
 
-    for( edge candidate : edges ) {
+    for( const edge &candidate : edges ) {
         const size_t i = candidate.second.first;
         const size_t j = candidate.second.second;
         bool connect = false;
diff --git a/src/profession.cpp b/src/profession.cpp
index 4c7182dade5c8..7356e1e01349e 100644
--- a/src/profession.cpp
+++ b/src/profession.cpp
@@ -732,7 +732,7 @@ std::map<spell_id, int> profession::spells() const
 
 void profession::learn_spells( avatar &you ) const
 {
-    for( const std::pair<spell_id, int> spell_pair : spells() ) {
+    for( const std::pair<const spell_id, int> &spell_pair : spells() ) {
         you.magic->learn_spell( spell_pair.first, you, true );
         spell &sp = you.magic->get_spell( spell_pair.first );
         while( sp.get_level() < spell_pair.second && !sp.is_max_level( you ) ) {
diff --git a/src/turret.cpp b/src/turret.cpp
index da3f36186cbad..9e83815fd3f8e 100644
--- a/src/turret.cpp
+++ b/src/turret.cpp
@@ -633,16 +633,16 @@ int vehicle::automatic_fire_turret( vehicle_part &pt )
             if( boo_hoo ) {
                 cpu.get_name() = string_format( pgettext( "vehicle turret", "The %s" ), pt.name() );
                 // check if the player can see or hear then print chooses a message accordingly
-                if( u_see & u_hear ) {
+                if( u_see && u_hear ) {
                     add_msg( m_warning, n_gettext( "%s points in your direction and emits an IFF warning beep.",
                                                    "%s points in your direction and emits %d annoyed sounding beeps.",
                                                    boo_hoo ),
                              cpu.get_name(), boo_hoo );
-                } else if( !u_see & u_hear ) {
+                } else if( !u_see && u_hear ) {
                     add_msg( m_warning, n_gettext( "You hear a warning beep.",
                                                    "You hear %d annoyed sounding beeps.",
                                                    boo_hoo ), boo_hoo );
-                } else if( u_see & !u_hear ) {
+                } else if( u_see && !u_hear ) {
                     add_msg( m_warning, _( "%s points in your direction." ), cpu.get_name() );
                 }
             }
diff --git a/tests/overmap_test.cpp b/tests/overmap_test.cpp
index 0a076bbad0712..2f7be6504a482 100644
--- a/tests/overmap_test.cpp
+++ b/tests/overmap_test.cpp
@@ -362,7 +362,7 @@ static void finalize_item_counts( std::unordered_map<itype_id, float> &item_coun
                 }
             }
         }
-        for( std::pair<const itype_id, int> demographics : category.second.item_weights ) {
+        for( const std::pair<const itype_id, int> &demographics : category.second.item_weights ) {
             item_counts[demographics.first] = 0.0;
         }
     }
diff --git a/tests/vehicle_export_test.cpp b/tests/vehicle_export_test.cpp
index e08844a5bcbfe..c9975b0a50ce7 100644
--- a/tests/vehicle_export_test.cpp
+++ b/tests/vehicle_export_test.cpp
@@ -24,7 +24,7 @@ static bool operator==( const vehicle_prototype::part_def &l, const vehicle_prot
 
 static bool operator==( const vehicle_item_spawn &l, const vehicle_item_spawn &r )
 {
-    return l.pos == r.pos && l.chance == r.chance && l.with_ammo == r.with_ammo &&
+    return l.pos == r.pos && l.chance == r.chance &&
            l.with_ammo == r.with_ammo && l.with_magazine == r.with_magazine && l.item_ids == r.item_ids &&
            // NOLINTNEXTLINE(misc-redundant-expression)
            l.variant_ids == r.variant_ids && l.item_groups == r.item_groups;
diff --git a/tests/vehicle_part_test.cpp b/tests/vehicle_part_test.cpp
index 81c9d179c8593..32adbb9774f99 100644
--- a/tests/vehicle_part_test.cpp
+++ b/tests/vehicle_part_test.cpp
@@ -137,7 +137,7 @@ static void test_craft_via_rig( const std::vector<item> &items, int give_battery
     // Shift skill levels by one to ensure successful crafting
     // after the change in https://github.com/CleverRaven/Cataclysm-DDA/pull/61985
     character.set_skill_level( recipe.skill_used, recipe.difficulty + 1 );
-    for( const std::pair<skill_id, int> req : recipe.required_skills ) {
+    for( const std::pair<const skill_id, int> &req : recipe.required_skills ) {
         character.set_skill_level( req.first, req.second + 1 );
     }
     for( const recipe_proficiency &prof : recipe.proficiencies ) {