diff --git a/src/build/flags_clang.mak b/src/build/flags_clang.mak
index 412985cebd8..1368bbf0032 100644
--- a/src/build/flags_clang.mak
+++ b/src/build/flags_clang.mak
@@ -9,9 +9,6 @@ CCOMFLAGS += -Wno-self-assign-field
 # caused by src/emu/cpu/tms34010/34010gfx.c
 CCOMFLAGS += -Wno-shift-count-overflow
 
-# caused by src/emu/video/stvvdp2.c
-CCOMFLAGS += -Wno-constant-logical-operand
-
 # TODO: needs to use $(CC)
 TEST_CLANG := $(shell clang --version)
 
diff --git a/src/emu/cpu/h8/h8_timer16.c b/src/emu/cpu/h8/h8_timer16.c
index 3167329c044..5c4ec70a86e 100644
--- a/src/emu/cpu/h8/h8_timer16.c
+++ b/src/emu/cpu/h8/h8_timer16.c
@@ -298,7 +298,7 @@ void h8_timer16_channel_device::recalc_event(UINT64 cur_time)
 		else
 			event_time = 0;
 
-		if(LOG_EVENT_TIME && event_time)
+		if(event_time && LOG_EVENT_TIME)
 			logerror("%s: next event in %d cycles (%ld)\n", tag(), int(event_time - cpu->total_cycles()), long(event_time));
 
 	} else {
diff --git a/src/emu/video/stvvdp2.c b/src/emu/video/stvvdp2.c
index c5416f0bb49..7ba64f3044f 100644
--- a/src/emu/video/stvvdp2.c
+++ b/src/emu/video/stvvdp2.c
@@ -2,6 +2,7 @@
 
 #define DEBUG_MODE 0
 #define TEST_FUNCTIONS 0
+#define POPMESSAGE_DEBUG 0
 
 /*
 
@@ -4431,13 +4432,13 @@ void saturn_state::stv_vdp2_check_tilemap(bitmap_rgb32 &bitmap, const rectangle
 		//  popmessage("Sprite Window enabled");
 
 		/* Capcom Collection Dai 2 - Choh Makaimura (Duh!) */
-		if(STV_VDP2_MZCTL & 0x1f && 0)
+		if(STV_VDP2_MZCTL & 0x1f && POPMESSAGE_DEBUG)
 			popmessage("Mosaic control enabled = %04x\n",STV_VDP2_MZCTL);
 
 		/* Bio Hazard bit 1 */
 		/* Airs Adventure 0x3e */
 		/* Bakuretsu Hunter */
-		if(STV_VDP2_LNCLEN & ~2 && 0)
+		if(STV_VDP2_LNCLEN & ~2 && POPMESSAGE_DEBUG)
 			popmessage("Line Colour screen enabled %04x %08x, contact MAMEdev",STV_VDP2_LNCLEN,STV_VDP2_LCTAU<<16|STV_VDP2_LCTAL);
 
 		/* Bio Hazard 0x400 = extended color calculation enabled */
@@ -4448,7 +4449,7 @@ void saturn_state::stv_vdp2_check_tilemap(bitmap_rgb32 &bitmap, const rectangle
 			popmessage("Gradation enabled %04x, contact MAMEdev",STV_VDP2_CCCR);
 
 		/* Advanced VG, Shining Force III */
-		if(STV_VDP2_SFCCMD && 0)
+		if(STV_VDP2_SFCCMD && POPMESSAGE_DEBUG)
 			popmessage("Special Color Calculation enable %04x, contact MAMEdev",STV_VDP2_SFCCMD);
 
 		/* Cleopatra Fortune Transparent Shadow */
@@ -4470,7 +4471,7 @@ void saturn_state::stv_vdp2_check_tilemap(bitmap_rgb32 &bitmap, const rectangle
 			popmessage("Reduction enable %04x, contact MAMEdev",STV_VDP2_ZMCTL);
 
 		/* Burning Rangers and friends FMV, J.League Pro Soccer Club Wo Tsukurou!! backgrounds */
-		if(STV_VDP2_SCRCTL & 0x0101 && 0)
+		if(STV_VDP2_SCRCTL & 0x0101 && POPMESSAGE_DEBUG)
 			popmessage("Vertical cell scroll enable %04x, contact MAMEdev",STV_VDP2_SCRCTL);
 
 		/* Magical Drop III 0x200 -> color calculation window */
diff --git a/src/mame/video/jagblit.inc b/src/mame/video/jagblit.inc
index 98a00b64562..b2af11b1e40 100644
--- a/src/mame/video/jagblit.inc
+++ b/src/mame/video/jagblit.inc
@@ -344,11 +344,8 @@ void jaguar_state::FUNCNAME(UINT32 command, UINT32 a1flags, UINT32 a2flags)
 	}
 
 	/* check for unhandled command bits */
-	if (LOG_UNHANDLED_BLITS)
-	{
-		if (COMMAND & 0x24003000)
-			logerror("Blitter unhandled: these command bits: %08X\n", COMMAND & 0x24003000);
-	}
+	if ((COMMAND & 0x24003000) && LOG_UNHANDLED_BLITS)
+		logerror("Blitter unhandled: these command bits: %08X\n", COMMAND & 0x24003000);
 
 	/* top of the outer loop */
 	outer = outer_count;