diff --git a/filesystem.hpp b/filesystem.hpp
index 0754eda..2a64341 100644
--- a/filesystem.hpp
+++ b/filesystem.hpp
@@ -31,10 +31,10 @@ string canonical( const string &path );
 
 class Directory {
 public:
-    Directory( const string &path_ );
     Directory() = delete;
-    Directory( const Directory &d ) = default;
-    Directory( Directory &&d ) = default;
+    explicit Directory( const string &path_ );
+    explicit Directory( const Directory &d ) = default;
+    explicit Directory( Directory &&d ) = default;
 
     class Iterator {
     public:
@@ -42,7 +42,7 @@ public:
         ~Iterator();
 
 #ifdef _WIN32
-        Iterator( bool ended_ );
+        explicit Iterator( bool ended_ );
 #else
         Iterator( const Directory &d_, const struct dirent *current_entry_ );
 #endif
diff --git a/functions.cpp b/functions.cpp
index 1ebcf87..8b79061 100644
--- a/functions.cpp
+++ b/functions.cpp
@@ -431,7 +431,7 @@ void prepareDB( const string &_pattern ) {
         db.open( getDBName(), SQLite::OPEN_READWRITE | SQLite::OPEN_CREATE );
     } catch ( std::exception &e ) {
         cerr << _( DB_NOT_CREATE ) << " " << getDBName() << std::endl;
-        throw e;
+        throw;
     }
     db.exec(
         "CREATE TABLE IF NOT EXISTS SHOWS (ID INTEGER NOT NULL "
@@ -474,7 +474,7 @@ void addToDB( const string &show, const string &path, const string &language,
         db.open( getDBName(), SQLite::OPEN_READWRITE | SQLite::OPEN_CREATE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
 #ifndef GUI
     // gui gives id and correct show name
@@ -588,7 +588,7 @@ void refreshDB( bool linux, void *progress_ptr ) {
         db.open( getDBName(), SQLite::OPEN_READWRITE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
 
     db.exec( "DELETE FROM EPISODES;" );
@@ -643,10 +643,9 @@ void refreshDB( bool linux, void *progress_ptr ) {
             p.print( _( UPDATING_IN_DB, show[TEXT( "SHOW" )].c_str() ) );
             p.print( 0 );
             i = 0;
-            size_t j{};
             size_t addition = 100 / seasons_size;
             for ( auto &season : seasons ) {
-                j = 0;
+                size_t j = 0;
                 size_t smalladdition = addition / season.second.size();
                 for ( auto &episode : season.second ) {
                     db.exec( TEXT( "INSERT INTO EPISODES ( SHOWID, PATH ) "
@@ -680,7 +679,7 @@ void updateDB( bool linux, void *progress_ptr ) {
         db.open( getDBName(), SQLite::OPEN_READWRITE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
     db.exec(
         TEXT( "SELECT ID, TVID, SHOW, PATH, LANGUAGE, DVD FROM SHOWS WHERE TVID"
@@ -766,7 +765,7 @@ void changeDBPattern( const string &pattern ) {
         db.open( getDBName(), SQLite::OPEN_READWRITE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
     db.exec( TEXT( "UPDATE SHOWS SET PATH = '" ) + pattern +
              TEXT( "' WHERE TVID == 'pattern';" ) );
@@ -785,7 +784,7 @@ void cleanDB( void *progress_ptr ) {
         db.open( getDBName(), SQLite::OPEN_READWRITE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
     db.exec( TEXT( "SELECT ID, PATH FROM SHOWS WHERE TVID"
                    " != 'pattern';" ),
@@ -840,7 +839,7 @@ void removeFromDB( const string &path ) {
         db.open( getDBName(), SQLite::OPEN_READWRITE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
     string show_id{};
     db.exec( TEXT( "SELECT ID FROM SHOWS WHERE PATH == '" ) + sanitize( path ) +
@@ -860,7 +859,7 @@ std::vector< std::unordered_map< string, string > > dbGetShows() {
         db.open( getDBName(), SQLite::OPEN_READWRITE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
     std::vector< std::unordered_map< string, string > > ret;
     db.exec( TEXT( "SELECT * FROM SHOWS;" ), ret );
@@ -877,7 +876,7 @@ void changeDB( size_t index, const string &path, const string &language,
         db.open( getDBName(), SQLite::OPEN_READWRITE | SQLite::OPEN_CREATE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
 #ifndef _WIN32
     string show_id = std::to_string( index );
@@ -913,7 +912,7 @@ void refreshSelectDB( std::unordered_set< size_t > indexes, bool linux,
         db.open( getDBName(), SQLite::OPEN_READWRITE );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
     db.exec( TEXT( "DELETE FROM EPISODES WHERE SHOWID IN " ) + index_list +
              TEXT( ";" ) );
@@ -974,7 +973,7 @@ string getDBPattern() {
         db.open( getDBName(), SQLite::OPEN_READONLY );
     } catch ( std::exception &e ) {
         cerr << _( DB_CANT_OPEN ) << std::endl;
-        throw e;
+        throw;
     }
     string pattern{};
     db.exec( TEXT( "SELECT PATH FROM SHOWS WHERE TVID == 'pattern';" ),
diff --git a/gtk/mainwindow.hpp b/gtk/mainwindow.hpp
index 8660b12..3ed6741 100644
--- a/gtk/mainwindow.hpp
+++ b/gtk/mainwindow.hpp
@@ -19,7 +19,7 @@
 
 class MainWindow : public Gtk::Window {
 public:
-    MainWindow( const Glib::RefPtr< Gtk::Application > &ptr );
+    explicit MainWindow( const Glib::RefPtr< Gtk::Application > &ptr );
     virtual ~MainWindow();
 
 private: