Reverting part of changes from previous commits as described in mail on list (nw)

src/emu/diserial.cpp

@@ -454,12 +454,12 @@ uint8_t device_serial_interface::transmit_register_get_data_bit()
 
 bool device_serial_interface::is_receive_register_full()
 {
-	return (m_rcv_flags & RECEIVE_REGISTER_FULL) != 0;
+	return m_rcv_flags & RECEIVE_REGISTER_FULL;
 }
 
 bool device_serial_interface::is_transmit_register_empty()
 {
-	return (m_tra_flags & TRANSMIT_REGISTER_EMPTY) != 0;
+	return m_tra_flags & TRANSMIT_REGISTER_EMPTY;
 }
 
 const char *device_serial_interface::parity_tostring(parity_t parity)

src/emu/diserial.h

@@ -109,7 +109,7 @@ protected:
 
 	bool is_receive_register_full();
 	bool is_transmit_register_empty();
-	bool is_receive_register_synchronized() const { return (m_rcv_flags & RECEIVE_REGISTER_SYNCHRONISED) != 0; }
+	bool is_receive_register_synchronized() const { return m_rcv_flags & RECEIVE_REGISTER_SYNCHRONISED; }
 	bool is_receive_register_shifting() const { return m_rcv_bit_count_received > 0; }
 	bool is_receive_framing_error() const { return m_rcv_framing_error; }
 	bool is_receive_parity_error() const { return m_rcv_parity_error; }

src/emu/distate.h

@@ -63,7 +63,7 @@ public:
 	void *dataptr() const { return m_dataptr.v; }
 	const char *symbol() const { return m_symbol.c_str(); }
 	bool visible() const { return ((m_flags & DSF_NOSHOW) == 0); }
-	bool divider() const { return ((m_flags & DSF_DIVIDER) != 0); }
+	bool divider() const { return m_flags & DSF_DIVIDER; }
 	device_state_interface *parent_state() const {return m_device_state;}
 
 protected:

src/emu/ioport.cpp

@@ -2516,7 +2516,7 @@ bool ioport_manager::playback_read<bool>(bool &result)
 {
 	uint8_t temp;
 	playback_read(temp);
-	return result = temp != 0;
+	return result = bool(temp);
 }
 
 

src/emu/render.cpp

@@ -967,7 +967,7 @@ render_target::render_target(render_manager &manager, const internal_layout *lay
 	m_layerconfig = m_base_layerconfig;
 
 	// load the layout files
-	load_layout_files(layoutfile, (flags & RENDER_CREATE_SINGLE_FILE) != 0);
+	load_layout_files(layoutfile, flags & RENDER_CREATE_SINGLE_FILE);
 
 	// set the current view to the first one
 	set_view(0);
@@ -1219,7 +1219,7 @@ void render_target::compute_visible_area(int32_t target_width, int32_t target_he
 			int scale_mode = m_scale_mode;
 			if (m_scale_mode == SCALE_FRACTIONAL_AUTO)
 			{
-				bool is_rotated = ((m_manager.machine().system().flags & ORIENTATION_SWAP_XY) ^ (target_orientation & ORIENTATION_SWAP_XY)) != 0;
+				bool is_rotated = (m_manager.machine().system().flags & ORIENTATION_SWAP_XY) ^ (target_orientation & ORIENTATION_SWAP_XY);
 				scale_mode = is_rotated ^ target_is_portrait ? SCALE_FRACTIONAL_Y : SCALE_FRACTIONAL_X;
 			}
 
@@ -2235,27 +2235,27 @@ void render_target::config_load(xml_data_node &targetnode)
 	// modify the artwork config
 	int tmpint = xml_get_attribute_int(&targetnode, "backdrops", -1);
 	if (tmpint == 0 || tmpint == 1)
-		set_backdrops_enabled(tmpint != 0);
+		set_backdrops_enabled(tmpint);
 
 	tmpint = xml_get_attribute_int(&targetnode, "overlays", -1);
 	if (tmpint == 0 || tmpint == 1)
-		set_overlays_enabled(tmpint != 0);
+		set_overlays_enabled(tmpint);
 
 	tmpint = xml_get_attribute_int(&targetnode, "bezels", -1);
 	if (tmpint == 0 || tmpint == 1)
-		set_bezels_enabled(tmpint != 0);
+		set_bezels_enabled(tmpint);
 
 	tmpint = xml_get_attribute_int(&targetnode, "cpanels", -1);
 	if (tmpint == 0 || tmpint == 1)
-		set_cpanels_enabled(tmpint != 0);
+		set_cpanels_enabled(tmpint);
 
 	tmpint = xml_get_attribute_int(&targetnode, "marquees", -1);
 	if (tmpint == 0 || tmpint == 1)
-		set_marquees_enabled(tmpint != 0);
+		set_marquees_enabled(tmpint);
 
 	tmpint = xml_get_attribute_int(&targetnode, "zoom", -1);
 	if (tmpint == 0 || tmpint == 1)
-		set_zoom_to_screen(tmpint != 0);
+		set_zoom_to_screen(tmpint);
 
 	// apply orientation
 	tmpint = xml_get_attribute_int(&targetnode, "rotate", -1);

src/emu/screen.cpp

@@ -246,7 +246,7 @@ void screen_device_svg_renderer::output_change(const char *outname, int32_t valu
 	auto l = m_key_ids.find(outname);
 	if (l == m_key_ids.end())
 		return;
-	m_key_state[l->second] = value != 0;
+	m_key_state[l->second] = value;
 }
 
 void screen_device_svg_renderer::compute_initial_bboxes(std::vector<bbox> &bboxes)

src/emu/sound.cpp

@@ -1060,7 +1060,7 @@ void sound_manager::update(void *ptr, int param)
 	// force all the speaker streams to generate the proper number of samples
 	int samples_this_update = 0;
 	for (speaker_device &speaker : speaker_device_iterator(machine().root_device()))
-		speaker.mix(&m_leftmix[0], &m_rightmix[0], samples_this_update, (m_muted & MUTE_REASON_SYSTEM) != 0);
+		speaker.mix(&m_leftmix[0], &m_rightmix[0], samples_this_update, (m_muted & MUTE_REASON_SYSTEM));
 
 	// now downmix the final result
 	uint32_t finalmix_step = machine().video().speed_factor();

src/lib/util/flac.cpp

@@ -355,7 +355,7 @@ bool flac_decoder::reset()
 				&flac_decoder::metadata_callback_static,
 				&flac_decoder::error_callback_static, this) != FLAC__STREAM_DECODER_INIT_STATUS_OK)
 		return false;
-	return FLAC__stream_decoder_process_until_end_of_metadata(m_decoder) != 0;
+	return FLAC__stream_decoder_process_until_end_of_metadata(m_decoder);
 }
 
 

src/lib/util/options.h

@@ -86,7 +86,7 @@ public:
 		uint32_t flags() const { return m_flags; }
 		bool is_header() const { return type() == OPTION_HEADER; }
 		bool is_command() const { return type() == OPTION_COMMAND; }
-		bool is_internal() const { return (m_flags & OPTION_FLAG_INTERNAL) != 0; }
+		bool is_internal() const { return m_flags & OPTION_FLAG_INTERNAL; }
 		bool has_range() const { return (!m_minimum.empty() && !m_maximum.empty()); }
 		int priority() const { return m_priority; }
 		bool is_changed() const { return m_changed; }

src/lib/util/unzip.cpp

@@ -620,16 +620,16 @@ class general_flag_reader
 public:
 	general_flag_reader(std::uint16_t val) : m_value(val) { }
 
-	bool        encrypted() const               { return (m_value & 0x0001) != 0; }
-	bool        implode_8k_dict() const         { return (m_value & 0x0002) != 0; }
-	bool        implode_3_trees() const         { return (m_value & 0x0004) != 0; }
+	bool        encrypted() const               { return bool(m_value & 0x0001); }
+	bool        implode_8k_dict() const         { return bool(m_value & 0x0002); }
+	bool        implode_3_trees() const         { return bool(m_value & 0x0004); }
 	unsigned    deflate_option() const          { return unsigned((m_value >> 1) & 0x0003); }
-	bool        lzma_eos_mark() const           { return (m_value & 0x0002) != 0; }
-	bool        use_descriptor() const          { return (m_value & 0x0008) != 0; }
-	bool        patch_data() const              { return (m_value & 0x0020) != 0; }
-	bool        strong_encryption() const       { return (m_value & 0x0040) != 0; }
-	bool        utf8_encoding() const           { return (m_value & 0x0800) != 0; }
-	bool        directory_encryption() const    { return (m_value & 0x2000) != 0; }
+	bool        lzma_eos_mark() const           { return bool(m_value & 0x0002); }
+	bool        use_descriptor() const          { return bool(m_value & 0x0008); }
+	bool        patch_data() const              { return bool(m_value & 0x0020); }
+	bool        strong_encryption() const       { return bool(m_value & 0x0040); }
+	bool        utf8_encoding() const           { return bool(m_value & 0x0800); }
+	bool        directory_encryption() const    { return bool(m_value & 0x2000); }
 
 private:
 	std::uint16_t m_value;

src/lib/util/vecstream.h

@@ -148,8 +148,8 @@ public:
 protected:
 	virtual pos_type seekoff(off_type off, std::ios_base::seekdir dir, std::ios_base::openmode which = std::ios_base::in | std::ios_base::out) override
 	{
-		bool const in((which & std::ios_base::in) != 0);
-		bool const out((which & std::ios_base::out) != 0);
+		bool const in(which & std::ios_base::in);
+		bool const out(which & std::ios_base::out);
 		if ((!in && !out) ||
 			(in && out && (std::ios_base::cur == dir)) ||
 			(in && !(m_mode & std::ios_base::in)) ||