fixes for variables set but not used

scripts/src/3rdparty.lua

@@ -1196,6 +1196,11 @@ project "bimg"
 		end
 	end
 
+	configuration { "gmake" }
+		buildoptions {
+			"-Wno-unused-but-set-variable",
+		}
+
 	defines {
 		"__STDC_LIMIT_MACROS",
 		"__STDC_FORMAT_MACROS",
@@ -2220,6 +2225,11 @@ project "asmjit"
 		end
 	end
 
+	configuration { "gmake" }
+		buildoptions {
+			"-Wno-unused-but-set-variable",
+		}
+
 	files {
 		MAME_DIR .. "3rdparty/asmjit/src/asmjit/asmjit.h",
 		MAME_DIR .. "3rdparty/asmjit/src/asmjit/core.h",

src/devices/cpu/arcompact/arcompact_execute.cpp

@@ -6564,7 +6564,7 @@ ARCOMPACT_RETTYPE arcompact_device::arcompact_handle04_21_p10(OPS_32)
 ARCOMPACT_RETTYPE arcompact_device::arcompact_handle04_21_p11_m0(OPS_32) // Jcc.D   (no link, delay)
 {
 	int size = 4;
-	uint32_t limm;
+	[[maybe_unused]] uint32_t limm;
 	int got_limm = 0;
 
 	COMMON32_GET_creg

src/emu/debug/dvdisasm.cpp

@@ -57,12 +57,12 @@ debug_view_disasm::debug_view_disasm(running_machine &machine, debug_view_osd_up
 		throw std::bad_alloc();
 
 	// count the number of comments
-	int total_comments = 0;
-	for(auto &source : m_source_list)
-	{
-		const debug_view_disasm_source &dasmsource = downcast<const debug_view_disasm_source &>(*source);
-		total_comments += dasmsource.device()->debug()->comment_count();
-	}
+	//int total_comments = 0;
+	//for(auto &source : m_source_list)
+	//{
+		//const debug_view_disasm_source &dasmsource = downcast<const debug_view_disasm_source &>(*source);
+		//total_comments += dasmsource.device()->debug()->comment_count();
+	//}
 
 	// configure the view
 	m_total.y = DEFAULT_DASM_LINES;

src/lib/formats/dfi_dsk.cpp

@@ -85,7 +85,7 @@ bool dfi_format::load(util::random_read &io, uint32_t form_factor, const std::ve
 	std::vector<uint8_t> data;
 	int onerev_time = 0; // time for one revolution, used to guess clock and rpm for DFE2 files
 	unsigned long clock_rate = 100000000; // sample clock rate in megahertz
-	int rpm=360; // drive rpm
+	[[maybe_unused]] int rpm=360; // drive rpm
 	while(pos < size) {
 		uint8_t h[10];
 		io.read_at(pos, h, 10, actual);
@@ -161,8 +161,6 @@ bool dfi_format::load(util::random_read &io, uint32_t form_factor, const std::ve
 			osd_printf_verbose("dfi_dsk: Actual rpm based on index: %f\n", ((double)clock_rate/(double)onerev_time)*60);
 		}
 
-		rpm += 0;   // HACK: prevent GCC 4.6+ from warning "variable set but unused"
-
 		if(!index_time)
 			index_time = total_time;
 

src/lib/formats/fdd_dsk.cpp

@@ -88,7 +88,7 @@ bool fdd_format::load(util::random_read &io, uint32_t form_factor, const std::ve
 
 	for (int track = 0; track < 160; track++)
 	{
-		int curr_num_sec = 0, curr_track_size = 0;
+		int curr_num_sec = 0; [[maybe_unused]] int curr_track_size = 0;
 		for (int sect = 0; sect < 26; sect++)
 		{
 			// read sector map for this sector

src/lib/formats/ti99_dsk.cpp

@@ -570,7 +570,7 @@ int ti99_floppy_format::get_sectors(const std::vector<bool> &bitstream, int enco
 	int seccount = 0;
 	uint16_t shift_reg = 0;
 	uint8_t databyte = 0;
-	uint8_t curbyte = 0;
+	[[maybe_unused]] uint8_t curbyte = 0;
 	int rep = 0;
 	int cursect = 0;
 

src/lib/formats/vt_dsk.cpp

@@ -119,7 +119,7 @@ std::vector<uint8_t> vtech_common_format::flux_to_image(floppy_image *image)
 		int pos = 0;
 		int count = 0;
 		uint8_t *dest = nullptr;
-		uint16_t checksum = 0;
+		[[maybe_unused]] uint16_t checksum = 0;
 		uint64_t buf = 0;
 		sz = bitstream.size();
 		if(sz < 128)
@@ -283,7 +283,7 @@ bool vtech_dsk_format::load(util::random_read &io, uint32_t form_factor, const s
 
 	int mode = 0;
 	int count = 0;
-	uint16_t checksum = 0;
+	[[maybe_unused]] uint16_t checksum = 0;
 	uint64_t buf = 0;
 	uint8_t *dest = nullptr;
 

src/mame/drivers/cobra.cpp

@@ -881,8 +881,8 @@ void cobra_renderer::render_color_scan(int32_t scanline, const extent_t &extent,
 	float dgg = extent.param[POLY_G].dpdx;
 	float gb = extent.param[POLY_B].start;
 	float dgb = extent.param[POLY_B].dpdx;
-	float ga = extent.param[POLY_A].start;
-	float dga = extent.param[POLY_A].dpdx;
+	[[maybe_unused]] float ga = extent.param[POLY_A].start;
+	[[maybe_unused]] float dga = extent.param[POLY_A].dpdx;
 
 	uint32_t zmode = extradata.zmode;
 
@@ -967,8 +967,8 @@ void cobra_renderer::render_texture_scan(int32_t scanline, const extent_t &exten
 	float dgg = extent.param[POLY_G].dpdx;
 	float gb = extent.param[POLY_B].start;
 	float dgb = extent.param[POLY_B].dpdx;
-	float ga = extent.param[POLY_A].start;
-	float dga = extent.param[POLY_A].dpdx;
+	[[maybe_unused]] float ga = extent.param[POLY_A].start;
+	[[maybe_unused]] float dga = extent.param[POLY_A].dpdx;
 
 	uint32_t *const fb = &m_backbuffer->pix(scanline);
 	float *const zb = (float*)&m_zbuffer->pix(scanline);

src/mame/drivers/gunpey.cpp

@@ -880,7 +880,7 @@ bool gunpey_state::decompress_sprite(unsigned char *buf, int ix, int iy, int ow,
 	s.ox = 0;
 	s.oy = 0;
 
-	int temp;
+	[[maybe_unused]] int temp;
 	temp = get_next_bit(&s);
 	temp |= get_next_bit(&s) << 1;
 	temp |= get_next_bit(&s) << 2;

src/mame/drivers/nemesis.cpp

@@ -3097,7 +3097,7 @@ void nemesis_state::bubsys_twinbeeb_init()
 
 	for (int i = 0; i < 0x806; i++)
 	{
-		uint16_t crc = 0;
+		[[maybe_unused]] uint16_t crc = 0;
 
 		int sourcebase = i * 0x80;
 		int destbase = i * 0x90;

src/mame/machine/seicopbl.cpp

@@ -269,7 +269,7 @@ void seibu_cop_bootleg_device::cmd_trigger_w(offs_t offset, uint16_t data)
 		*/
 		case 0x8100:
 		{
-			uint16_t sin_offs; //= m_host_space->read_dword(m_reg[0]+(0x34));
+			[[maybe_unused]] uint16_t sin_offs; //= m_host_space->read_dword(m_reg[0]+(0x34));
 			sin_offs = m_host_space->read_byte(m_reg[0]+(0x35));
 			sin_offs |= m_host_space->read_byte(m_reg[0]+(0x37)) << 8;
 			int raw_angle = (m_host_space->read_word(m_reg[0]+(0x34^2)) & 0xff);

src/mame/video/3dom2_te.cpp

@@ -2433,7 +2433,7 @@ void m2_te_device::destination_blend(uint32_t x, uint32_t y, uint32_t w, const r
 	bool winclipdis = false;
 
 	// Z Status
-	uint32_t zgel = 0;
+	[[maybe_unused]] uint32_t zgel = 0;
 
 	uint32_t zaddr;
 

src/mame/video/fmtowns.cpp

@@ -1422,7 +1422,7 @@ void towns_state::render_text_char(uint8_t x, uint8_t y, uint8_t ascii, uint16_t
 				temp |= ((colour & 0x0f) << 4);
 			if(data & (1<<(b+1)))
 				temp |= (colour & 0x0f);
-			//m_towns_gfxvram[0x40000+vram_addr+(b/2)] = temp;
+			m_towns_gfxvram[0x40000+vram_addr+(b/2)] = temp;
 		}
 
 		vram_addr += linesize;

src/mame/video/midtunit.cpp

@@ -440,7 +440,7 @@ void midtunit_video_device::dma_draw()
 	while (iy < height)
 	{
 		int startskip = m_dma_state.startskip << 8;
-		int endskip = m_dma_state.endskip << 8;
+		[[maybe_unused]] int endskip = m_dma_state.endskip << 8;
 		int width = m_dma_state.width << 8;
 		int sx = m_dma_state.xpos;
 		int ix = 0;
@@ -922,7 +922,7 @@ void midtunit_video_device::log_bitmap(int command, int bpp, bool Skip)
 	for (int y = 0; y < m_dma_state.height; y++)
 	{
 		int startskip = m_dma_state.startskip;
-		int endskip = m_dma_state.endskip;
+		[[maybe_unused]] int endskip = m_dma_state.endskip;
 		int width = m_dma_state.width;
 		int ix = 0;
 		int tx;

src/mame/video/model2.cpp

@@ -2420,7 +2420,7 @@ u32 *model2_state::geo_code_upload( geo_state *geo, u32 opcode, u32 *input )
 
 	for( i = 0; i < count; i++ )
 	{
-		u64  code;
+		[[maybe_unused]] u64  code;
 
 		/* read the top part of the opcode */
 		code = *input++;