Initialise a few variables in h files.

src/mame/includes/aussiebyte.h

@@ -116,19 +116,19 @@ private:
 	void mem_map(address_map &map);
 
 	u8 crt8002(u8 ac_ra, u8 ac_chr, u8 ac_attr, u16 ac_cnt, bool ac_curs);
-	bool m_port15; // rom switched in (0), out (1)
+	bool m_port15 = 0; // rom switched in (0), out (1)
-	u8 m_port17;
+	u8 m_port17 = 0U;
-	u8 m_port17_rdy;
+	u8 m_port17_rdy = 0U;
-	u8 m_port19;
+	u8 m_port19 = 0U;
-	u8 m_port1a; // bank to switch to when write to port 15 happens
+	u8 m_port1a = 0U; // bank to switch to when write to port 15 happens
-	u8 m_port28;
+	u8 m_port28 = 0U;
-	u8 m_port34;
+	u8 m_port34 = 0U;
-	u8 m_port35; // byte to be written to vram or aram
+	u8 m_port35 = 0U; // byte to be written to vram or aram
-	u8 m_video_index;
+	u8 m_video_index = 0U;
-	u16 m_cnt;
+	u16 m_cnt = 0U;
-	u16 m_alpha_address;
+	u16 m_alpha_address = 0U;
-	u16 m_graph_address;
+	u16 m_graph_address = 0U;
-	bool m_centronics_busy;
+	bool m_centronics_busy = 0;
 	std::unique_ptr<u8[]> m_vram; // video ram, 64k dynamic
 	std::unique_ptr<u8[]> m_aram; // attribute ram, 2k static
 	std::unique_ptr<u8[]> m_ram;  // main ram, 256k dynamic

src/mame/includes/kaypro.h

@@ -91,17 +91,17 @@ private:
 
 	void mc6845_screen_configure();
 
-	u8 m_mc6845_reg[32];
+	u8 m_mc6845_reg[32]{};
-	u8 m_mc6845_ind;
+	u8 m_mc6845_ind = 0U;
-	u8 m_framecnt;
+	u8 m_framecnt = 0U;
 	std::unique_ptr<u8[]> m_ram;
 	std::unique_ptr<u8[]> m_vram; // video ram
 	std::unique_ptr<u8[]> m_dummy;  // black hole for write to rom
 	int m_centronics_busy;
-	bool m_is_motor_off;
+	bool m_is_motor_off = 0;
-	u8 m_fdc_rq;
+	u8 m_fdc_rq = 0U;
-	u8 m_system_port;
+	u8 m_system_port = 0U;
-	uint16_t m_mc6845_video_address;
+	u16 m_mc6845_video_address = 0U;
 	floppy_image_device *m_floppy;
 
 	required_device<palette_device> m_palette;

src/mame/includes/osi.h

@@ -33,8 +33,6 @@ class sb2m600_state : public driver_device
 public:
 	sb2m600_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag)
-		, m_cassbit(0)
-		, m_cassold(0)
 		, m_maincpu(*this, M6502_TAG)
 		, m_acia(*this, "acia")
 		, m_cass(*this, "cassette")
@@ -69,9 +67,9 @@ protected:
 	void osi630_video(machine_config &config);
 	void osi600_mem(address_map &map);
 
-	uint8_t m_cass_data[4];
+	uint8_t m_cass_data[4]{};
-	bool m_cassbit;
+	bool m_cassbit = 0;
-	bool m_cassold;
+	bool m_cassold = 0;
 	required_device<cpu_device> m_maincpu;
 	required_device<acia6850_device> m_acia;
 	required_device<cassette_image_device> m_cass;
@@ -85,14 +83,14 @@ protected:
 	required_ioport m_io_reset;
 
 	/* floppy state */
-	int m_fdc_index;
+	int m_fdc_index = 0;
 
 	/* keyboard state */
-	uint8_t m_keylatch;
+	uint8_t m_keylatch = 0U;
 
 	/* video state */
-	int m_32;
+	int m_32 = 0;
-	int m_coloren;
+	int m_coloren = 0;
 };
 
 class c1p_state : public sb2m600_state

src/mame/includes/phc25.h

@@ -51,8 +51,8 @@ private:
 	void machine_start() override;
 	void machine_reset() override;
 	uint8_t *m_char_rom;
-	uint8_t m_port40;
+	uint8_t m_port40 = 0U;
-	int m_centronics_busy;
+	int m_centronics_busy = 0;
 	required_shared_ptr<uint8_t> m_vram;
 	required_device<cpu_device> m_maincpu;
 	required_device<mc6847_base_device> m_vdg;

src/mame/includes/poly.h

@@ -64,13 +64,13 @@ public:
 		, m_maincpu(*this, "maincpu")
 		, m_bankdev(*this, "bankdev")
 		, m_ram(*this, RAM_TAG)
-		, m_trom(*this, "saa5050_%u", 1)
+		, m_trom(*this, "saa5050_%u", 1U)
-		, m_pia(*this, "pia%u", 0)
+		, m_pia(*this, "pia%u", 0U)
 		, m_adlc(*this, "mc6854")
 		, m_ptm(*this, "ptm")
 		, m_irqs(*this, "irqs")
 //      , m_kr2376(*this, "kr2376")
-		, m_kbd(*this, "X%u", 0)
+		, m_kbd(*this, "X%u", 0U)
 		, m_modifiers(*this, "MODIFIERS")
 		, m_speaker(*this, "speaker")
 		, m_user(*this, "user")
@@ -140,12 +140,12 @@ private:
 	required_shared_ptr<uint8_t> m_dat;
 	optional_device<acia6850_device> m_acia;
 	optional_device<clock_device> m_acia_clock;
-	uint8_t m_video_pa, m_video_pb;
+	uint8_t m_video_pa = 0U, m_video_pb = 0U;
-	uint8_t m_term_data;
+	uint8_t m_term_data = 0U;
 
 	inline offs_t physical(offs_t offset);
 
-	int m_dat_bank;
+	int m_dat_bank = 0;
 };
 
 
@@ -155,7 +155,7 @@ public:
 	polydev_state(const machine_config &mconfig, device_type type, const char *tag)
 		: poly_state(mconfig, type, tag)
 		, m_fdc(*this, "fdc")
-		, m_floppy(*this, "fdc:%u", 0)
+		, m_floppy(*this, "fdc:%u", 0U)
 		, m_current_floppy(nullptr)
 	{
 	}

src/mame/includes/sorcerer.h

@@ -76,7 +76,7 @@ public:
 		, m_floppy43(*this, "fdc4:3")
 		, m_iop_config(*this, "CONFIG")
 		, m_iop_vs(*this, "VS")
-		, m_iop_x(*this, "X.%u", 0)
+		, m_iop_x(*this, "X.%u", 0U)
 	{ }
 
 	void sorcerer(machine_config &config);
@@ -108,8 +108,8 @@ protected:
 	void sorcerera_io(address_map &map);
 	void sorcererb_io(address_map &map);
 
-	u8 m_portfe;
+	u8 m_portfe = 0U;
-	u8 m_keyboard_line;
+	u8 m_keyboard_line = 0U;
 	emu_timer *m_serial_timer;
 	emu_timer *m_cassette_timer;
 	cass_data_t m_cass_data;
@@ -151,7 +151,7 @@ private:
 	void port34_w(u8 data);
 	void port48_w(u8 data);
 	void intrq4_w(bool state);
-	bool m_halt;
+	bool m_halt = 0;
 	virtual void machine_start() override;
 	virtual void machine_reset() override;
 	void busreq_w(bool state);
@@ -178,10 +178,10 @@ private:
 	void port2c_w(u8 data);
 	void intrq2_w(bool state);
 	void drq2_w(bool state);
-	u8 m_port2c;
+	u8 m_port2c = 0U;
-	bool m_wait;
+	bool m_wait = 0;
-	bool m_drq_off;
+	bool m_drq_off = 0;
-	bool m_intrq_off;
+	bool m_intrq_off = 0;
 	virtual void machine_start() override;
 	virtual void machine_reset() override;
 	optional_device<micropolis_device> m_fdc;

src/mame/includes/super80.h

@@ -67,14 +67,14 @@ protected:
 	void pio_port_a_w(u8 data);
 	u8 pio_port_b_r();
 	u8 portf2_r();
-	u8 m_portf0;
+	u8 m_portf0 = 0U;
-	u8 m_s_options;
+	u8 m_s_options = 0U;
-	u8 m_palette_index;
+	u8 m_palette_index = 0U;
-	u8 m_keylatch;
+	u8 m_keylatch = 0U;
-	u8 m_cass_data[4];
+	u8 m_cass_data[4]{};
-	u8 m_key_pressed;
+	u8 m_key_pressed = 0U;
-	u8 m_last_data;
+	u8 m_last_data = 0U;
-	bool m_boot_in_progress;
+	bool m_boot_in_progress = 0;
 	void super80m_palette(palette_device &palette) const;
 	TIMER_DEVICE_CALLBACK_MEMBER(timer_k);
 	TIMER_DEVICE_CALLBACK_MEMBER(kansas_r);

src/mame/includes/trs80m3.h

@@ -110,25 +110,25 @@ private:
 	void m4_banked_mem(address_map &map);
 	void m4p_banked_mem(address_map &map);
 
-	uint8_t m_model4;
+	uint8_t m_model4 = 0U;
-	uint8_t m_mode;
+	uint8_t m_mode = 0U;
-	uint8_t m_irq;
+	uint8_t m_irq = 0U;
-	uint8_t m_mask;
+	uint8_t m_mask = 0U;
-	uint8_t m_nmi_mask;
+	uint8_t m_nmi_mask = 0U;
-	uint8_t m_port_ec;
+	uint8_t m_port_ec = 0U;
-	bool m_reg_load;
+	bool m_reg_load = 0;
-	uint8_t m_nmi_data;
+	uint8_t m_nmi_data = 0U;
-	uint8_t m_cassette_data;
+	uint8_t m_cassette_data = 0U;
 	emu_timer *m_cassette_data_timer;
-	double m_old_cassette_val;
+	double m_old_cassette_val = 0;
-	uint16_t m_start_address;
+	uint16_t m_start_address = 0U;
-	uint8_t m_crtc_reg;
+	uint8_t m_crtc_reg = 0U;
-	uint8_t m_size_store;
+	uint8_t m_size_store = 0U;
-	bool m_a11_flipflop;
+	bool m_a11_flipflop = 0;
-	uint16_t m_timeout;
+	uint16_t m_timeout = 0U;
-	bool m_wait;
+	bool m_wait = 0;
-	bool m_drq_off;
+	bool m_drq_off = 0;
-	bool m_intrq_off;
+	bool m_intrq_off = 0;
 	floppy_image_device *m_fdd;
 	required_device<cpu_device> m_maincpu;
 	required_memory_region m_region_maincpu;

src/mame/includes/zorba.h

@@ -117,15 +117,15 @@ private:
 
 	required_device<ieee488_device>     m_ieee;
 
-	uint8_t m_intmask;
+	uint8_t m_intmask = 0U;
-	uint8_t m_tx_rx_rdy;
+	uint8_t m_tx_rx_rdy = 0U;
-	uint8_t m_irq;
+	uint8_t m_irq = 0U;
 
-	bool    m_printer_prowriter;
+	bool    m_printer_prowriter = 0;
-	int     m_printer_fault;
+	int     m_printer_fault = 0;
-	int     m_printer_select;
+	int     m_printer_select = 0;
 
-	uint8_t m_term_data;
+	uint8_t m_term_data = 0U;
 };
 
 #endif // MAME_INCLUDES_ZORBA_H