release v0.18.5

Using pcm_resample_lsr_32() for 24 bit samples works, but may cause 24
bit overflows.  This commit makes 24 bit a special case with explicit
clipping.

NEWS

@@ -1,3 +1,25 @@
+ver 0.18.5 (2013/11/23)
+* configuration
+  - fix crash when db_file is configured without music_directory
+  - fix crash on "stats" without db_file/music_directory
+* database
+  - proxy: auto-reload statistics
+  - proxy: provide "db_update" in "stats" response
+* input
+  - curl: work around stream resume bug (fixed in libcurl 7.32.0)
+* decoder
+  - fluidsynth: auto-detect by default
+* clip 24 bit data from libsamplerate
+* fix ia64, mipsel and other little-endian architectures
+* fix build failures due to missing includes
+* fix build failure with static libmpdclient
+
+ver 0.18.4 (2013/11/13)
+* decoder
+  - dsdiff: fix byte order bug
+* fix build failures due to missing includes
+* libc++ compatibility
+
 ver 0.18.3 (2013/11/08)
 * fix stuck MPD after song change (0.18.2 regression)
 

configure.ac

@@ -1,6 +1,6 @@
 AC_PREREQ(2.60)
 
-AC_INIT(mpd, 0.18.3, musicpd-dev-team@lists.sourceforge.net)
+AC_INIT(mpd, 0.18.5, musicpd-dev-team@lists.sourceforge.net)
 
 VERSION_MAJOR=0
 VERSION_MINOR=18
@@ -874,10 +874,12 @@ AM_CONDITIONAL(HAVE_FLAC, test x$enable_flac = xyes)
 enable_flac_encoder=$enable_flac
 
 dnl -------------------------------- FluidSynth -------------------------------
+
+MPD_AUTO_PKG(fluidsynth, FLUIDSYNTH, [fluidsynth >= 1.1],
+	[fluidsynth decoder], [fluidsynth not found])
+
 if test x$enable_fluidsynth = xyes; then
-	PKG_CHECK_MODULES(FLUIDSYNTH, [fluidsynth >= 1.1],
-		AC_DEFINE(ENABLE_FLUIDSYNTH, 1, [Define for fluidsynth support]),
-		enable_fluidsynth=no)
+	AC_DEFINE(ENABLE_FLUIDSYNTH, 1, [Define for fluidsynth support])
 fi
 
 AM_CONDITIONAL(ENABLE_FLUIDSYNTH, test x$enable_fluidsynth = xyes)

doc/mpdconf.example

@@ -210,7 +210,6 @@ input {
 #	type		"alsa"
 #	name		"My ALSA Device"
 ##	device		"hw:0,0"	# optional
-##	format		"44100:16:2"	# optional
 ##	mixer_type      "hardware"	# optional
 ##	mixer_device	"default"	# optional
 ##	mixer_control	"PCM"		# optional
@@ -223,7 +222,6 @@ input {
 #	type		"oss"
 #	name		"My OSS Device"
 ##	device		"/dev/dsp"	# optional
-##	format		"44100:16:2"	# optional
 ##	mixer_type      "hardware"	# optional
 ##	mixer_device	"/dev/mixer"	# optional
 ##	mixer_control	"PCM"		# optional
@@ -327,12 +325,6 @@ input {
 #	mixer_type      "none"			# optional
 #}
 #
-# This setting will change all decoded audio to be converted to the specified
-# format before being passed to the audio outputs. By default, this setting is
-# disabled.
-#
-#audio_output_format		"44100:16:2"
-#
 # If MPD has been compiled with libsamplerate support, this setting specifies 
 # the sample rate converter to use.  Possible values can be found in the 
 # mpd.conf man page or the libsamplerate documentation. By default, this is

src/DatabaseGlue.cxx

@@ -148,12 +148,12 @@ DatabaseGlobalOpen(Error &error)
 	return true;
 }
 
-time_t
-db_get_mtime(void)
+bool
+db_exists()
 {
 	assert(db != nullptr);
 	assert(db_is_open);
 	assert(db_is_simple());
 
-	return ((SimpleDatabase *)db)->GetLastModified();
+	return ((SimpleDatabase *)db)->GetUpdateStamp() > 0;
 }

src/DatabasePlugin.hxx

@@ -30,6 +30,8 @@
 #include "tag/TagType.h"
 #include "Compiler.h"
 
+#include <time.h>
+
 struct config_param;
 struct DatabaseSelection;
 struct db_visitor;
@@ -132,6 +134,13 @@ public:
 	virtual bool GetStats(const DatabaseSelection &selection,
 			      DatabaseStats &stats,
 			      Error &error) const = 0;
+
+	/**
+	 * Returns the time stamp of the last database update.
+	 * Returns 0 if that is not not known/available.
+	 */
+	gcc_pure
+	virtual time_t GetUpdateStamp() const = 0;
 };
 
 struct DatabasePlugin {

src/DatabaseSimple.hxx

@@ -62,25 +62,13 @@ db_get_directory(const char *name);
 bool
 db_save(Error &error);
 
-/**
- * May only be used if db_is_simple() returns true.
- */
-gcc_pure
-time_t
-db_get_mtime(void);
-
 /**
  * Returns true if there is a valid database file on the disk.
  *
  * May only be used if db_is_simple() returns true.
  */
 gcc_pure
-static inline bool
-db_exists(void)
-{
-	/* mtime is set only if the database file was loaded or saved
-	   successfully */
-	return db_get_mtime() > 0;
-}
+bool
+db_exists();
 
 #endif

src/DecoderAPI.cxx

@@ -35,6 +35,7 @@
 #include <assert.h>
 #include <stdlib.h>
 #include <string.h>
+#include <math.h>
 
 void
 decoder_initialized(Decoder &decoder,

src/DecoderThread.cxx

@@ -38,6 +38,8 @@
 #include "tag/ApeReplayGain.hxx"
 #include "Log.hxx"
 
+#include <functional>
+
 static constexpr Domain decoder_thread_domain("decoder_thread");
 
 /**

src/DespotifyUtils.cxx

@@ -28,6 +28,8 @@ extern "C" {
 #include <despotify.h>
 }
 
+#include <stdio.h>
+
 const Domain despotify_domain("despotify");
 
 static struct despotify_session *g_session;

src/Mapper.cxx

@@ -133,7 +133,9 @@ void mapper_finish(void)
 const char *
 mapper_get_music_directory_utf8(void)
 {
-	return music_dir_utf8.c_str();
+	return music_dir_utf8.empty()
+		? nullptr
+		: music_dir_utf8.c_str();
 }
 
 const AllocatedPath &

src/Mapper.hxx

@@ -41,7 +41,8 @@ mapper_init(AllocatedPath &&music_dir, AllocatedPath &&playlist_dir);
 void mapper_finish(void);
 
 /**
- * Return the absolute path of the music directory encoded in UTF-8.
+ * Return the absolute path of the music directory encoded in UTF-8 or
+ * nullptr if no music directory was configured.
  */
 gcc_const
 const char *

src/SongSave.cxx

@@ -30,6 +30,7 @@
 #include "util/Domain.hxx"
 
 #include <string.h>
+#include <stdlib.h>
 
 #define SONG_MTIME "mtime"
 #define SONG_END "song_end"

src/Stats.cxx

@@ -30,59 +30,75 @@
 
 #include <glib.h>
 
-struct stats stats;
+static GTimer *uptime;
+static DatabaseStats stats;
 
 void stats_global_init(void)
 {
-	stats.timer = g_timer_new();
+	uptime = g_timer_new();
 }
 
 void stats_global_finish(void)
 {
-	g_timer_destroy(stats.timer);
+	g_timer_destroy(uptime);
 }
 
 void stats_update(void)
 {
+	assert(GetDatabase() != nullptr);
+
 	Error error;
 
 	DatabaseStats stats2;
 
 	const DatabaseSelection selection("", true);
 	if (GetDatabase()->GetStats(selection, stats2, error)) {
-		stats.song_count = stats2.song_count;
-		stats.song_duration = stats2.total_duration;
-		stats.artist_count = stats2.artist_count;
-		stats.album_count = stats2.album_count;
+		stats = stats2;
 	} else {
 		LogError(error);
 
-		stats.song_count = 0;
-		stats.song_duration = 0;
-		stats.artist_count = 0;
-		stats.album_count = 0;
+		stats.Clear();
 	}
 }
 
+static void
+db_stats_print(Client &client)
+{
+	assert(GetDatabase() != nullptr);
+
+	if (!db_is_simple())
+		/* reload statistics if we're using the "proxy"
+		   database plugin */
+		/* TODO: move this into the "proxy" database plugin as
+		   an "idle" handler */
+		stats_update();
+
+	client_printf(client,
+		      "artists: %u\n"
+		      "albums: %u\n"
+		      "songs: %u\n"
+		      "db_playtime: %lu\n",
+		      stats.artist_count,
+		      stats.album_count,
+		      stats.song_count,
+		      stats.total_duration);
+
+	const time_t update_stamp = GetDatabase()->GetUpdateStamp();
+	if (update_stamp > 0)
+		client_printf(client,
+			      "db_update: %lu\n",
+			      (unsigned long)update_stamp);
+}
+
 void
 stats_print(Client &client)
 {
 	client_printf(client,
-		      "artists: %u\n"
-		      "albums: %u\n"
-		      "songs: %i\n"
-		      "uptime: %li\n"
-		      "playtime: %li\n"
-		      "db_playtime: %li\n",
-		      stats.artist_count,
-		      stats.album_count,
-		      stats.song_count,
-		      (long)g_timer_elapsed(stats.timer, NULL),
-		      (long)(client.player_control.GetTotalPlayTime() + 0.5),
-		      stats.song_duration);
+		      "uptime: %lu\n"
+		      "playtime: %lu\n",
+		      (unsigned long)g_timer_elapsed(uptime, NULL),
+		      (unsigned long)(client.player_control.GetTotalPlayTime() + 0.5));
 
-	if (db_is_simple())
-		client_printf(client,
-			      "db_update: %li\n",
-			      (long)db_get_mtime());
+	if (GetDatabase() != nullptr)
+		db_stats_print(client);
 }

src/Stats.hxx

@@ -21,26 +21,6 @@
 #define MPD_STATS_HXX
 
 class Client;
-typedef struct _GTimer GTimer;
-
-struct stats {
-	GTimer *timer;
-
-	/** number of song files in the music directory */
-	unsigned song_count;
-
-	/** sum of all song durations in the music directory (in
-	    seconds) */
-	unsigned long song_duration;
-
-	/** number of distinct artist names in the music directory */
-	unsigned artist_count;
-
-	/** number of distinct album names in the music directory */
-	unsigned album_count;
-};
-
-extern struct stats stats;
 
 void stats_global_init(void);
 

src/archive/Iso9660ArchivePlugin.cxx

@@ -190,18 +190,16 @@ iso9660_input_read(InputStream *is, void *ptr, size_t size,
 		   Error &error)
 {
 	Iso9660InputStream *iis = (Iso9660InputStream *)is;
-	int toread, readed = 0;
+	int readed = 0;
 	int no_blocks, cur_block;
 	size_t left_bytes = iis->statbuf->size - is->offset;
 
 	size = (size * ISO_BLOCKSIZE) / ISO_BLOCKSIZE;
 
 	if (left_bytes < size) {
-		toread = left_bytes;
 		no_blocks = CEILING(left_bytes,ISO_BLOCKSIZE);
 	} else {
-		toread = size;
-		no_blocks = toread / ISO_BLOCKSIZE;
+		no_blocks = size / ISO_BLOCKSIZE;
 	}
 	if (no_blocks > 0) {
 

src/db/ProxyDatabasePlugin.cxx

@@ -46,6 +46,9 @@ class ProxyDatabase : public Database {
 	struct mpd_connection *connection;
 	Directory *root;
 
+	/* this is mutable because GetStats() must be "const" */
+	mutable time_t update_stamp;
+
 public:
 	static Database *Create(const config_param &param,
 				Error &error);
@@ -71,6 +74,10 @@ public:
 			      DatabaseStats &stats,
 			      Error &error) const override;
 
+	virtual time_t GetUpdateStamp() const override {
+		return update_stamp;
+	}
+
 private:
 	bool Configure(const config_param &param, Error &error);
 
@@ -237,6 +244,7 @@ ProxyDatabase::Open(Error &error)
 		return false;
 
 	root = Directory::NewRoot();
+	update_stamp = 0;
 
 	return true;
 }
@@ -631,6 +639,8 @@ ProxyDatabase::GetStats(const DatabaseSelection &selection,
 	if (stats2 == nullptr)
 		return CheckError(connection, error);
 
+	update_stamp = (time_t)mpd_stats_get_db_update_time(stats2);
+
 	stats.song_count = mpd_stats_get_number_of_songs(stats2);
 	stats.total_duration = mpd_stats_get_db_play_time(stats2);
 	stats.artist_count = mpd_stats_get_number_of_artists(stats2);

src/db/SimpleDatabasePlugin.hxx

@@ -26,8 +26,6 @@
 
 #include <cassert>
 
-#include <time.h>
-
 struct Directory;
 
 class SimpleDatabase : public Database {
@@ -55,11 +53,6 @@ public:
 
 	bool Save(Error &error);
 
-	gcc_pure
-	time_t GetLastModified() const {
-		return mtime;
-	}
-
 	static Database *Create(const config_param &param,
 				Error &error);
 
@@ -85,6 +78,10 @@ public:
 			      DatabaseStats &stats,
 			      Error &error) const override;
 
+	virtual time_t GetUpdateStamp() const override {
+		return mtime;
+	}
+
 protected:
 	bool Configure(const config_param &param, Error &error);
 

src/decoder/DsdLib.hxx

@@ -47,6 +47,17 @@ public:
 	}
 };
 
+class DffDsdUint64 {
+	uint32_t hi;
+	uint32_t lo;
+
+public:
+	constexpr uint64_t Read() const {
+		return (uint64_t(FromBE32(hi)) << 32) |
+			uint64_t(FromBE32(lo));
+	}
+};
+
 bool
 dsdlib_read(Decoder *decoder, InputStream &is,
 	    void *data, size_t length);

src/decoder/DsdiffDecoderPlugin.cxx

@@ -43,13 +43,13 @@
 
 struct DsdiffHeader {
 	DsdId id;
-	DsdUint64 size;
+	DffDsdUint64 size;
 	DsdId format;
 };
 
 struct DsdiffChunkHeader {
 	DsdId id;
-	DsdUint64 size;
+	DffDsdUint64 size;
 
 	/**
 	 * Read the "size" attribute from the specified header, converting it
@@ -294,7 +294,6 @@ dsdiff_read_metadata_extra(Decoder *decoder, InputStream &is,
 			if (!dsdiff_read_chunk_header(decoder, is, chunk_header))
 				return false;
 		}
-		chunk_size = 0;
 	}
 	/* done processing chunk headers, process tags if any */
 
@@ -385,10 +384,10 @@ dsdiff_decode_chunk(Decoder &decoder, InputStream &is,
 	while (chunk_size > 0) {
 		/* see how much aligned data from the remaining chunk
 		   fits into the local buffer */
-		unsigned now_frames = buffer_frames;
 		size_t now_size = buffer_size;
 		if (chunk_size < (uint64_t)now_size) {
-			now_frames = (unsigned)chunk_size / frame_size;
+			unsigned now_frames =
+				(unsigned)chunk_size / frame_size;
 			now_size = now_frames * frame_size;
 		}
 

src/decoder/DsfDecoderPlugin.cxx

@@ -240,10 +240,10 @@ dsf_decode_chunk(Decoder &decoder, InputStream &is,
 	while (chunk_size > 0) {
 		/* see how much aligned data from the remaining chunk
 		   fits into the local buffer */
-		unsigned now_frames = buffer_frames;
 		size_t now_size = buffer_size;
 		if (chunk_size < (uint64_t)now_size) {
-			now_frames = (unsigned)chunk_size / frame_size;
+			unsigned now_frames =
+				(unsigned)chunk_size / frame_size;
 			now_size = now_frames * frame_size;
 		}
 

src/decoder/OggFind.cxx

@@ -22,6 +22,8 @@
 #include "OggSyncState.hxx"
 #include "util/Error.hxx"
 
+#include <stdio.h>
+
 bool
 OggFindEOS(OggSyncState &oy, ogg_stream_state &os, ogg_packet &packet)
 {

src/encoder/OpusEncoderPlugin.cxx

@@ -34,6 +34,7 @@
 #include <glib.h>
 
 #include <assert.h>
+#include <stdlib.h>
 
 struct opus_encoder {
 	/** the base class */

src/filter/RouteFilterPlugin.cxx

@@ -56,6 +56,7 @@
 #include <assert.h>
 #include <string.h>
 #include <stdint.h>
+#include <stdlib.h>
 
 class RouteFilter final : public Filter {
 	/**

src/input/CurlInputPlugin.cxx

@@ -273,12 +273,27 @@ public:
 		SocketAction(CURL_SOCKET_TIMEOUT, 0);
 	}
 
+	/**
+	 * This is a kludge to allow pausing/resuming a stream with
+	 * libcurl < 7.32.0.  Read the curl_easy_pause manpage for
+	 * more information.
+	 */
+	void ResumeSockets() {
+		int running_handles;
+		curl_multi_socket_all(multi, &running_handles);
+	}
+
 private:
 	static int TimerFunction(CURLM *multi, long timeout_ms, void *userp);
 
 	virtual void OnTimeout() override;
 };
 
+/**
+ * libcurl version number encoded in a 24 bit integer.
+ */
+static unsigned curl_version_num;
+
 /** libcurl should accept "ICY 200 OK" */
 static struct curl_slist *http_200_aliases;
 
@@ -330,6 +345,13 @@ input_curl_resume(struct input_curl *c)
 	if (c->paused) {
 		c->paused = false;
 		curl_easy_pause(c->easy, CURLPAUSE_CONT);
+
+		if (curl_version_num < 0x072000)
+			/* libcurl older than 7.32.0 does not update
+			   its sockets after curl_easy_pause(); force
+			   libcurl to do it now */
+			curl_multi->ResumeSockets();
+
 		curl_multi->InvalidateSockets();
 	}
 }
@@ -586,6 +608,16 @@ input_curl_init(const config_param &param, Error &error)
 		return false;
 	}
 
+	const auto version_info = curl_version_info(CURLVERSION_FIRST);
+	if (version_info != nullptr) {
+		FormatDebug(curl_domain, "version %s", version_info->version);
+		if (version_info->features & CURL_VERSION_SSL)
+			FormatDebug(curl_domain, "with %s",
+				    version_info->ssl_version);
+
+		curl_version_num = version_info->version_num;
+	}
+
 	http_200_aliases = curl_slist_append(http_200_aliases, "ICY 200 OK");
 
 	proxy = param.GetBlockValue("proxy");

src/output/HttpdInternal.hxx

@@ -30,6 +30,11 @@
 #include "thread/Mutex.hxx"
 #include "event/ServerSocket.hxx"
 
+#ifdef _LIBCPP_VERSION
+/* can't use incomplete template arguments with libc++ */
+#include "HttpdClient.hxx"
+#endif
+
 #include <forward_list>
 
 struct config_param;

src/pcm/PcmResample.cxx

@@ -148,3 +148,26 @@ PcmResampler::Resample32(unsigned channels, unsigned src_rate,
 					src_rate, src_buffer, src_size,
 					dest_rate, dest_size_r);
 }
+
+const int32_t *
+PcmResampler::Resample24(unsigned channels, unsigned src_rate,
+			 const int32_t *src_buffer, size_t src_size,
+			 unsigned dest_rate, size_t *dest_size_r,
+			 Error &error_r)
+{
+#ifdef HAVE_LIBSAMPLERATE
+	if (pcm_resample_lsr_enabled())
+		return pcm_resample_lsr_24(this, channels,
+					   src_rate, src_buffer, src_size,
+					   dest_rate, dest_size_r,
+					   error_r);
+#else
+	(void)error_r;
+#endif
+
+	/* reuse the 32 bit code - the resampler code doesn't care if
+	   the upper 8 bits are actually used */
+	return pcm_resample_fallback_32(this, channels,
+					src_rate, src_buffer, src_size,
+					dest_rate, dest_size_r);
+}

src/pcm/PcmResample.hxx

@@ -124,13 +124,7 @@ struct PcmResampler {
 	const int32_t *Resample24(unsigned channels, unsigned src_rate,
 				  const int32_t *src_buffer, size_t src_size,
 				  unsigned dest_rate, size_t *dest_size_r,
-				  Error &error_r)
-	{
-		/* reuse the 32 bit code - the resampler code doesn't care if
-		   the upper 8 bits are actually used */
-		return Resample32(channels, src_rate, src_buffer, src_size,
-				  dest_rate, dest_size_r, error_r);
-	}
+				  Error &error_r);
 };
 
 bool

src/pcm/PcmResampleInternal.hxx

@@ -69,6 +69,15 @@ pcm_resample_lsr_32(PcmResampler *state,
 		    unsigned dest_rate, size_t *dest_size_r,
 		    Error &error);
 
+const int32_t *
+pcm_resample_lsr_24(PcmResampler *state,
+		    unsigned channels,
+		    unsigned src_rate,
+		    const int32_t *src_buffer,
+		    size_t src_size,
+		    unsigned dest_rate, size_t *dest_size_r,
+		    Error &error);
+
 #endif
 
 const int16_t *

src/pcm/PcmResampleLibsamplerate.cxx

@@ -19,6 +19,7 @@
 
 #include "config.h"
 #include "PcmResampleInternal.hxx"
+#include "PcmUtils.hxx"
 #include "util/ASCII.hxx"
 #include "util/Error.hxx"
 #include "util/Domain.hxx"
@@ -283,3 +284,27 @@ pcm_resample_lsr_32(PcmResampler *state,
 
 	return dest_buffer;
 }
+
+const int32_t *
+pcm_resample_lsr_24(PcmResampler *state,
+		    unsigned channels,
+		    unsigned src_rate,
+		    const int32_t *src_buffer, size_t src_size,
+		    unsigned dest_rate, size_t *dest_size_r,
+		    Error &error)
+{
+	const auto result = pcm_resample_lsr_32(state, channels,
+						src_rate, src_buffer, src_size,
+						dest_rate, dest_size_r,
+						error);
+	if (result != nullptr)
+		/* src_float_to_int_array() clamps for 32 bit
+		   integers; now make sure everything's fine for 24
+		   bit */
+		/* TODO: eliminate the 32 bit clamp to reduce overhead */
+		PcmClampN<int32_t, int32_t, 24>(const_cast<int32_t *>(result),
+						result,
+						*dest_size_r / sizeof(*result));
+
+	return result;
+}

src/pcm/PcmUtils.hxx

@@ -63,4 +63,16 @@ PcmClamp(U x)
 	return T(x);
 }
 
+/**
+ * Check if the values in this buffer are within the range of the
+ * provided bit size, and clamps them whenever necessary.
+ */
+template<typename T, typename U, unsigned bits>
+static inline void
+PcmClampN(T *dest, const U *src, unsigned n)
+{
+	while (n-- > 0)
+		*dest++ = PcmClamp<T, U, bits>(*src++);
+}
+
 #endif

src/system/ByteOrder.hxx

@@ -33,11 +33,23 @@
 #include <stdint.h>
 
 #if defined(__i386__) || defined(__x86_64__) || defined(__ARMEL__)
-#define IS_LITTLE_ENDIAN true
-#define IS_BIG_ENDIAN false
+/* well-known little-endian */
+#  define IS_LITTLE_ENDIAN true
+#  define IS_BIG_ENDIAN false
+#elif defined(__MIPSEB__)
+/* well-known big-endian */
+#  define IS_LITTLE_ENDIAN false
+#  define IS_BIG_ENDIAN true
 #else
-#define IS_LITTLE_ENDIAN false
-#define IS_BIG_ENDIAN true
+/* generic compile-time check */
+#  include <endian.h>
+#  if __BYTE_ORDER == __LITTLE_ENDIAN
+#    define IS_LITTLE_ENDIAN true
+#    define IS_BIG_ENDIAN false
+#  else
+#    define IS_LITTLE_ENDIAN false
+#    define IS_BIG_ENDIAN true
+#  endif
 #endif
 
 static inline constexpr bool

src/system/fd_util.h

@@ -104,6 +104,11 @@ socketpair_cloexec_nonblock(int domain, int type, int protocol, int sv[2]);
 
 #endif
 
+#ifdef HAVE_LIBMPDCLIENT
+/* Avoid symbol conflict with statically linked libmpdclient */
+#define socket_cloexec_nonblock socket_cloexec_nonblock_noconflict
+#endif
+
 /**
  * Wrapper for socket(), which sets the CLOEXEC and the NONBLOCK flag
  * (atomically if supported by the OS).

src/util/LazyRandomEngine.hxx

@@ -49,12 +49,12 @@ public:
 	 */
 	void AutoCreate();
 
-	result_type min() const {
-		return engine->min();
+	static constexpr result_type min() {
+		return std::mt19937::min();
 	}
 
-	result_type max() const {
-		return engine->max();
+	static constexpr result_type max() {
+		return std::mt19937::max();
 	}
 
 	result_type operator()() {

src/util/RefCount.hxx

@@ -42,7 +42,12 @@ class RefCount {
 	std::atomic_uint n;
 
 public:
-	constexpr RefCount():n(1) {}
+#ifndef _LIBCPP_VERSION
+	/* the "constexpr" is missing in libc++'s "atomic"
+	   implementation */
+	constexpr
+#endif
+	RefCount():n(1) {}
 
 	void Increment() {
 		++n;

test/run_convert.cxx

@@ -36,6 +36,7 @@
 
 #include <assert.h>
 #include <stddef.h>
+#include <stdlib.h>
 #include <unistd.h>
 
 static void