diff --git a/src/emulator.c b/src/emulator.c
index 58457382..b611d99d 100644
--- a/src/emulator.c
+++ b/src/emulator.c
@@ -682,13 +682,13 @@ void emu_render_frame(struct emu *emu) {
     frame_y = 0;
   } else if (emu->aspect_ratio == ASPECT_RATIO_16BY9) {
     frame_width = emu->video_width;
-    frame_height = frame_width * (9.0f / 16.0f);
+    frame_height = (int)(frame_width * (9.0f / 16.0f));
     frame_x = 0;
-    frame_y = (emu->video_height - frame_height) / 2.0f;
+    frame_y = (int)((emu->video_height - frame_height) / 2.0f);
   } else if (emu->aspect_ratio == ASPECT_RATIO_4BY3) {
     frame_height = emu->video_height;
-    frame_width = frame_height * (4.0f / 3.0f);
-    frame_x = (emu->video_width - frame_width) / 2.0f;
+    frame_width = (int)(frame_height * (4.0f / 3.0f));
+    frame_x = (int)((emu->video_width - frame_width) / 2.0f);
     frame_y = 0;
   } else {
     LOG_FATAL("unexpected aspect ratio %d", emu->aspect_ratio);
diff --git a/src/guest/aica/aica.c b/src/guest/aica/aica.c
index 495d1857..e96283c1 100644
--- a/src/guest/aica/aica.c
+++ b/src/guest/aica/aica.c
@@ -66,11 +66,11 @@ struct aica_channel {
   uint8_t *base;
 
   /* current position in the sound source */
-  int phase;
+  uint32_t phase;
   /* fractional remainder after phase increment */
-  int phasefrc;
+  uint32_t phasefrc;
   /* amount to step the sound source each sample */
-  int phaseinc;
+  uint32_t phaseinc;
 
   /* decoding state */
   sample_t prev_sample, prev_quant;
@@ -203,7 +203,7 @@ static inline sample_t aica_adjust_channel_volume(struct aica_channel *ch,
   return (in * y) >> 15;
 }
 
-static void aica_decode_adpcm(sample_t data, sample_t prev, sample_t prev_quant,
+static void aica_decode_adpcm(uint8_t data, sample_t prev, sample_t prev_quant,
                               sample_t *next, sample_t *next_quant) {
   /* the decoded value (n) = (1 - 2 * l4) * (l3 + l2/2 + l1/4 + 1/8) * quantized
      width (n) + decoded value (n - 1)
@@ -439,9 +439,9 @@ static float aica_channel_duration(struct aica_channel *ch) {
   return ch->data->LEA / hz;
 }
 
-static int aica_channel_phaseinc(struct aica_channel *ch) {
+static uint32_t aica_channel_phaseinc(struct aica_channel *ch) {
   /* by default, increment by one sample per step */
-  int phaseinc = AICA_PHASE_BASE;
+  uint32_t phaseinc = AICA_PHASE_BASE;
 
   /* FNS represents the fractional phase increment, used to linearly interpolate
      between samples. note, the phase increment has 18 total fractional bits,
@@ -543,7 +543,7 @@ static void aica_channel_step_one(struct aica *aica, struct aica_channel *ch) {
       case AICA_FMT_ADPCM:
       case AICA_FMT_ADPCM_STREAM: {
         int shift = (ch->phase & 1) << 2;
-        sample_t data = (ch->base[ch->phase >> 1] >> shift) & 0xf;
+        uint8_t data = (ch->base[ch->phase >> 1] >> shift) & 0xf;
         aica_decode_adpcm(data, ch->prev_sample, ch->prev_quant,
                           &ch->next_sample, &ch->next_quant);
       } break;
@@ -636,8 +636,8 @@ static void aica_generate_frames(struct aica *aica) {
     l = aica_adjust_master_volume(aica, l);
     r = aica_adjust_master_volume(aica, r);
 
-    buffer[frame * 2 + 0] = CLAMP(l, INT16_MIN, INT16_MAX);
-    buffer[frame * 2 + 1] = CLAMP(r, INT16_MIN, INT16_MAX);
+    buffer[frame * 2 + 0] = (int16_t)CLAMP(l, INT16_MIN, INT16_MAX);
+    buffer[frame * 2 + 1] = (int16_t)CLAMP(r, INT16_MIN, INT16_MAX);
   }
 
   dc_push_audio(dc, buffer, AICA_BATCH_SIZE);
diff --git a/src/guest/bios/bios.c b/src/guest/bios/bios.c
index c1ba54ac..6dd433fe 100644
--- a/src/guest/bios/bios.c
+++ b/src/guest/bios/bios.c
@@ -142,7 +142,6 @@ static void bios_override_flash_settings(struct bios *bios) {
 static void bios_validate_flash(struct bios *bios) {
   struct dreamcast *dc = bios->dc;
   struct flash *flash = dc->flash;
-  struct flash_header_block header;
 
   /* validate partition 0 (factory settings) */
   {
diff --git a/src/guest/bios/syscalls.c b/src/guest/bios/syscalls.c
index ba8d5035..3bf6d526 100644
--- a/src/guest/bios/syscalls.c
+++ b/src/guest/bios/syscalls.c
@@ -299,7 +299,7 @@ static void bios_gdrom_mainloop(struct bios *bios) {
       LOG_SYSCALL("GDC_GET_VER 0x%x", dst);
 
       const char *version = "GDC Version 1.10 1999-03-31";
-      const int len = strlen(version);
+      const int len = (int)strlen(version);
 
       as_memcpy_to_guest(space, dst, version, len);
 
diff --git a/src/guest/gdrom/disc.c b/src/guest/gdrom/disc.c
index 9d6c2d92..9e9da06c 100644
--- a/src/guest/gdrom/disc.c
+++ b/src/guest/gdrom/disc.c
@@ -31,7 +31,7 @@ static void disc_get_meta(struct disc *disc, struct disc_meta *meta) {
   memcpy(meta, tmp, sizeof(*meta));
 }
 
-int disc_read_bytes(struct disc *disc, int fad, int len, void *dst,
+int disc_read_bytes(struct disc *disc, int fad, int len, uint8_t *dst,
                     int dst_size) {
   CHECK_LE(len, dst_size);
 
@@ -56,7 +56,7 @@ int disc_read_bytes(struct disc *disc, int fad, int len, void *dst,
 }
 
 int disc_read_sectors(struct disc *disc, int fad, int num_sectors,
-                      int sector_fmt, int sector_mask, void *dst,
+                      int sector_fmt, int sector_mask, uint8_t *dst,
                       int dst_size) {
   struct track *track = disc_lookup_track(disc, fad);
   CHECK_NOTNULL(track);
diff --git a/src/guest/gdrom/disc.h b/src/guest/gdrom/disc.h
index d21184b2..550bc8ae 100644
--- a/src/guest/gdrom/disc.h
+++ b/src/guest/gdrom/disc.h
@@ -69,8 +69,9 @@ void disc_get_toc(struct disc *disc, int area, struct track **first_track,
 
 int disc_find_file(struct disc *disc, const char *filename, int *fad, int *len);
 int disc_read_sectors(struct disc *disc, int fad, int num_sectors,
-                      int sector_fmt, int sector_mask, void *dst, int dst_size);
-int disc_read_bytes(struct disc *disc, int fad, int len, void *dst,
+                      int sector_fmt, int sector_mask, uint8_t *dst,
+                      int dst_size);
+int disc_read_bytes(struct disc *disc, int fad, int len, uint8_t *dst,
                     int dst_size);
 
 #endif
diff --git a/src/guest/holly/holly.c b/src/guest/holly/holly.c
index f6a21801..fa8f3e52 100644
--- a/src/guest/holly/holly.c
+++ b/src/guest/holly/holly.c
@@ -164,7 +164,7 @@ static void holly_maple_dma(struct holly *hl) {
 #define SB_SUSP(ch) (hl->SB_ADSUSP + ((ch)*HOLLY_G2_NUM_REGS))
 #define HOLLY_INT_G2INT(ch) HOLLY_INTERRUPT(HOLLY_INT_NRM, (0x8000 << ch))
 
-static void (*g2_timers[])(void *);
+static void (*g2_timers[4])(void *);
 
 #define DEFINE_G2_DMA_TIMER(ch)                                       \
   static void holly_g2_dma_timer_channel##ch(void *data) {            \
@@ -193,7 +193,7 @@ DEFINE_G2_DMA_TIMER(1);
 DEFINE_G2_DMA_TIMER(2);
 DEFINE_G2_DMA_TIMER(3);
 
-static void (*g2_timers[])(void *) = {
+static void (*g2_timers[4])(void *) = {
     &holly_g2_dma_timer_channel0, &holly_g2_dma_timer_channel1,
     &holly_g2_dma_timer_channel2, &holly_g2_dma_timer_channel3,
 };
diff --git a/src/guest/sh4/sh4_mmu.c b/src/guest/sh4/sh4_mmu.c
index b424362d..2a85630e 100644
--- a/src/guest/sh4/sh4_mmu.c
+++ b/src/guest/sh4/sh4_mmu.c
@@ -18,7 +18,7 @@ enum {
 };
 
 static void sh4_mmu_utlb_sync(struct sh4 *sh4, struct sh4_tlb_entry *entry) {
-  int n = entry - sh4->utlb;
+  int n = (int)(entry - sh4->utlb);
 
   /* check if entry maps to sq region [0xe0000000, 0xe3ffffff] */
   if ((entry->hi.VPN & (0xfc000000 >> 10)) == (0xe0000000 >> 10)) {