atarist, fmtowns, megadriv, model3, pc6001: initialized some variables which were causing incorrect behaviours in drvnoclear debug builds

src/mame/drivers/atarist.cpp

@@ -1887,6 +1887,10 @@ void st_state::machine_start()
 	m_mfp->i4_w(1);
 	m_mfp->i5_w(1);
 	m_mfp->i7_w(1);
+
+	m_shifter_base = 0;
+	m_shifter_ofs = 0;
+	m_shifter_mode = 0;
 }
 
 

src/mame/drivers/fmtowns.cpp

@@ -2762,6 +2762,10 @@ void towns_state::machine_start()
 		m_flop[0]->get_device()->set_rpm(360);
 	if (m_flop[1]->get_device())
 		m_flop[1]->get_device()->set_rpm(360);
+
+	m_timer0 = 0;
+	m_timer1 = 0;
+	m_serial_irq_enable = 0;
 }
 
 void towns_state::machine_reset()

src/mame/drivers/model3.cpp

@@ -1364,7 +1364,16 @@ void model3_state::model3_init(int step)
 	m_sound_irq_enable = 0;
 	m_sound_timer->adjust(attotime::never);
 
+	m_irq_enable = 0;
+
+	m_pci_bus = 0;
+	m_pci_device = 0;
+	m_pci_function = 0;
+	m_pci_reg = 0;
+
 	m_dma_busy = 0;
+	m_dma_irq = 0;
+	m_dma_endian = 0;
 	m_real3d_dma_timer->adjust(attotime::never);
 
 	m_bank_crom->set_base(memregion( "user1" )->base() + 0x800000 ); /* banked CROM */

src/mame/drivers/pc6001.cpp

@@ -1407,6 +1407,8 @@ void pc6001sr_state::machine_reset()
 	m_sr_text_mode = false;
 	m_sr_text_rows = 20;
 
+	m_kludge = 0;
+
 	std::string region_tag;
 	m_cart_rom = memregion(region_tag.assign(m_cart->tag()).append(GENERIC_ROM_REGION_TAG).c_str());
 	// should this be mirrored into the EXROM regions? hard to tell without an actual cart dump...

src/mame/includes/fmtowns.h

@@ -160,6 +160,9 @@ protected:
 	void ux_mem(address_map &map);
 
 	virtual void driver_start() override;
+	virtual void machine_start() override;
+	virtual void machine_reset() override;
+	virtual void video_start() override;
 
 	required_device<ram_device> m_ram;
 	required_device<cpu_device> m_maincpu;
@@ -276,9 +279,6 @@ private:
 	optional_shared_ptr<uint32_t> m_nvram;
 	optional_shared_ptr<uint16_t> m_nvram16;
 
-	virtual void machine_start() override;
-	virtual void machine_reset() override;
-	virtual void video_start() override;
 	uint32_t screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect);
 	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
 
@@ -457,8 +457,10 @@ class marty_state : public towns_state
 		: towns_state(mconfig, type, tag)
 	{ }
 
-	virtual void driver_start() override;
 	void marty(machine_config &config);
+
+protected:
+	virtual void driver_start() override;
 };
 
 #endif // MAME_INCLUDES_FMTOWNS_H

src/mame/includes/megadriv.h

@@ -32,14 +32,6 @@ INPUT_PORTS_EXTERN( megadri6 );
 INPUT_PORTS_EXTERN( ssf2mdb );
 INPUT_PORTS_EXTERN( mk3mdb );
 
-struct genesis_z80_vars
-{
-	int z80_is_reset;
-	int z80_has_bus;
-	uint32_t z80_bank_addr;
-	std::unique_ptr<uint8_t[]> z80_prgram;
-};
-
 
 class md_base_state : public driver_device
 {
@@ -70,6 +62,14 @@ public:
 	ioport_port *m_io_pad_3b[4];
 	ioport_port *m_io_pad_6b[4];
 
+struct genesis_z80_vars
+{
+	int z80_is_reset = 0;
+	int z80_has_bus = 0;
+	uint32_t z80_bank_addr = 0;
+	std::unique_ptr<uint8_t[]> z80_prgram;
+};
+
 	genesis_z80_vars m_genz80;
 	int m_version_hi_nibble;
 

src/mame/includes/model3.h

@@ -144,6 +144,9 @@ public:
 	void init_lamachin();
 	void init_model3_15();
 
+protected:
+	virtual void video_start() override;
+
 private:
 	required_device<ppc_device> m_maincpu;
 	optional_device<lsi53c810_device> m_lsi53c810;
@@ -332,7 +335,6 @@ private:
 	void set_irq_line(uint8_t bit, int line);
 	void model3_init(int step);
 	// video
-	virtual void video_start() override;
 	uint32_t screen_update_model3(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect);
 	TILE_GET_INFO_MEMBER(tile_info_layer0_4bit);
 	TILE_GET_INFO_MEMBER(tile_info_layer1_4bit);

src/mame/includes/pc6001.h

@@ -231,6 +231,34 @@ public:
 		m_sr_irq_vectors(*this, "irq_vectors")
 	{ }
 
+	void pc6001sr(machine_config &config);
+
+protected:
+	virtual void video_start() override;
+	virtual void machine_reset() override;
+
+private:
+	uint8_t m_sr_bank_r[8];
+	uint8_t m_sr_bank_w[8];
+	uint8_t m_kludge;
+	bool m_sr_text_mode;
+	uint8_t m_sr_text_rows;
+	std::unique_ptr<uint8_t []> m_gvram;
+	uint8_t m_bitmap_yoffs,m_bitmap_xoffs;
+
+	enum{
+		SUB_CPU_IRQ = 0,
+		JOYSTICK_IRQ,
+		TIMER_IRQ,
+		VOICE_IRQ,
+		VRTC_IRQ,
+		RS232_IRQ,
+		PRINTER_IRQ,
+		EXT_IRQ
+	};
+
+	required_shared_ptr<uint8_t> m_sr_irq_vectors;
+
 	uint8_t hw_rev_r();
 	uint8_t sr_bank_rn_r(offs_t offset);
 	void sr_bank_rn_w(offs_t offset, uint8_t data);
@@ -255,35 +283,8 @@ public:
 
 	uint32_t screen_update_pc6001sr(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
 
-	void pc6001sr(machine_config &config);
-
 	void pc6001sr_io(address_map &map);
 	void pc6001sr_map(address_map &map);
-protected:
-	virtual void video_start() override;
-	virtual void machine_reset() override;
-
-private:
-	uint8_t m_sr_bank_r[8];
-	uint8_t m_sr_bank_w[8];
-	uint8_t m_kludge;
-	bool m_sr_text_mode;
-	uint8_t m_sr_text_rows;
-	uint8_t *m_gvram;
-	uint8_t m_bitmap_yoffs,m_bitmap_xoffs;
-
-	enum{
-		SUB_CPU_IRQ = 0,
-		JOYSTICK_IRQ,
-		TIMER_IRQ,
-		VOICE_IRQ,
-		VRTC_IRQ,
-		RS232_IRQ,
-		PRINTER_IRQ,
-		EXT_IRQ
-	};
-
-	required_shared_ptr<uint8_t> m_sr_irq_vectors;
 };
 
 #endif

src/mame/machine/model3.cpp

@@ -2,7 +2,7 @@
 // copyright-holders:R. Belmont, Ville Linde
 /*
 
-  machine/model3.c: functions emulating various aspects of the Model 3 hardware
+  machine/model3.cpp: functions emulating various aspects of the Model 3 hardware
 
 */
 

src/mame/video/pc6001.cpp

@@ -128,7 +128,8 @@ void pc6001mk2_state::video_start()
 void pc6001sr_state::video_start()
 {
 //  m_video_ram = auto_alloc_array_clear(machine(), uint8_t, 0x4000);
-	m_gvram = auto_alloc_array_clear(machine(), uint8_t, 320*256*8); // TODO: size
+	m_gvram = std::make_unique<uint8_t []>(320*256*8); // TODO: size
+	std::fill_n(m_gvram.get(), 320*256*8, 0);
 	save_pointer(NAME(m_gvram), 320*256*8);
 }