clang-tidy: default virtual destructors

Found with cppcoreguidelines-special-member-functions

Signed-off-by: Rosen Penev <rosenp@gmail.com>

src/encoder/EncoderInterface.hxx

@@ -35,7 +35,7 @@ class Encoder {
 public:
 	explicit Encoder(bool _implements_tag) noexcept
 		:implements_tag(_implements_tag) {}
-	virtual ~Encoder() noexcept {}
+	virtual ~Encoder() noexcept = default;
 
 	bool ImplementsTag() const noexcept {
 		return implements_tag;
@@ -111,7 +111,7 @@ public:
 
 class PreparedEncoder {
 public:
-	virtual ~PreparedEncoder() noexcept {}
+	virtual ~PreparedEncoder() noexcept = default;
 
 	/**
 	 * Opens the object.  You must call this prior to using it.

src/filter/Filter.hxx

@@ -36,7 +36,7 @@ protected:
 	}
 
 public:
-	virtual ~Filter() noexcept {}
+	virtual ~Filter() noexcept = default;
 
 	/**
 	 * Returns the #AudioFormat produced by FilterPCM().

src/filter/Prepared.hxx

@@ -27,7 +27,7 @@ class Filter;
 
 class PreparedFilter {
 public:
-	virtual ~PreparedFilter() {}
+	virtual ~PreparedFilter() = default;
 
 	/**
 	 * Opens the filter, preparing it for FilterPCM().

src/mixer/MixerInternal.hxx

@@ -57,7 +57,7 @@ public:
 
 	Mixer(const Mixer &) = delete;
 
-	virtual ~Mixer() {}
+	virtual ~Mixer() = default;
 
 	bool IsPlugin(const MixerPlugin &other) const noexcept {
 		return &plugin == &other;

src/neighbor/Explorer.hxx

@@ -49,7 +49,7 @@ public:
 	/**
 	 * Free instance data.
          */
-	virtual ~NeighborExplorer() noexcept {}
+	virtual ~NeighborExplorer() noexcept = default;
 
 	/**
          * Start exploring the neighborhood.

src/pcm/Resampler.hxx

@@ -31,7 +31,7 @@ struct AudioFormat;
  */
 class PcmResampler {
 public:
-	virtual ~PcmResampler() {}
+	virtual ~PcmResampler() = default;
 
 	/**
 	 * Opens the resampler, preparing it for Resample().

src/playlist/SongEnumerator.hxx

@@ -30,7 +30,7 @@ class DetachedSong;
  */
 class SongEnumerator {
 public:
-	virtual ~SongEnumerator() noexcept {}
+	virtual ~SongEnumerator() noexcept = default;
 
 	/**
 	 * Obtain the next song.  Returns nullptr if there are no more

src/song/ISongFilter.hxx

@@ -31,7 +31,7 @@ using ISongFilterPtr = std::unique_ptr<ISongFilter>;
 
 class ISongFilter {
 public:
-	virtual ~ISongFilter() noexcept {}
+	virtual ~ISongFilter() noexcept = default;
 
 	virtual ISongFilterPtr Clone() const noexcept = 0;
 

src/storage/StorageInterface.hxx

@@ -33,7 +33,7 @@ class StorageDirectoryReader {
 public:
 	StorageDirectoryReader() = default;
 	StorageDirectoryReader(const StorageDirectoryReader &) = delete;
-	virtual ~StorageDirectoryReader() noexcept {}
+	virtual ~StorageDirectoryReader() noexcept = default;
 
 	virtual const char *Read() noexcept = 0;
 
@@ -47,7 +47,7 @@ class Storage {
 public:
 	Storage() = default;
 	Storage(const Storage &) = delete;
-	virtual ~Storage() noexcept {}
+	virtual ~Storage() noexcept = default;
 
 	/**
 	 * Throws #std::runtime_error on error.