diff --git a/src/boards/269.c b/src/boards/269.c
index 0acef24..b62f50f 100644
--- a/src/boards/269.c
+++ b/src/boards/269.c
@@ -80,7 +80,7 @@ static uint8 unscrambleCHR(uint8 data) {
 }
 
 void Mapper269_Init(CartInfo *info) {
-	int i;
+	uint32 i;
 	GenMMC3_Init(info, 512, 0, 8, 0);
 	cwrap = M269CW;
 	pwrap = M269PW;
diff --git a/src/boards/KS7030.c b/src/boards/KS7030.c
index c6de258..fb61a7e 100644
--- a/src/boards/KS7030.c
+++ b/src/boards/KS7030.c
@@ -26,7 +26,7 @@
  */
 
 /* 2020-3-6 - update mirroring (negativeExponent)
-/* PRG-ROM Bank Select #1/Mirroring Select ($8000-$8FFF, write)
+ * PRG-ROM Bank Select #1/Mirroring Select ($8000-$8FFF, write)
  * A~FEDC BA98 7654 3210
  * -------------------
  *  1000 .... .... MBBB
diff --git a/src/cheat.c b/src/cheat.c
index cdf0aaf..0e82364 100644
--- a/src/cheat.c
+++ b/src/cheat.c
@@ -570,7 +570,7 @@ void FCEUI_CheatSearchBegin(void) {
 }
 
 
-static int INLINE CAbs(int x) {
+static INLINE int CAbs(int x) {
 	if (x < 0)
 		return(0 - x);
 	return x;
diff --git a/src/drivers/libretro/libretro-common/compat/compat_snprintf.c b/src/drivers/libretro/libretro-common/compat/compat_snprintf.c
index b69ad04..d7320cc 100644
--- a/src/drivers/libretro/libretro-common/compat/compat_snprintf.c
+++ b/src/drivers/libretro/libretro-common/compat/compat_snprintf.c
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (compat_snprintf.c).
@@ -33,12 +33,12 @@
 #if _MSC_VER < 1300
 #define _vscprintf c89_vscprintf_retro__
 
-static int c89_vscprintf_retro__(const char *format, va_list pargs)
+static int c89_vscprintf_retro__(const char *fmt, va_list pargs)
 {
    int retval;
    va_list argcopy;
    va_copy(argcopy, pargs);
-   retval = vsnprintf(NULL, 0, format, argcopy);
+   retval = vsnprintf(NULL, 0, fmt, argcopy);
    va_end(argcopy);
    return retval;
 }
@@ -46,38 +46,36 @@ static int c89_vscprintf_retro__(const char *format, va_list pargs)
 
 /* http://stackoverflow.com/questions/2915672/snprintf-and-visual-studio-2010 */
 
-int c99_vsnprintf_retro__(char *outBuf, size_t size, const char *format, va_list ap)
+int c99_vsnprintf_retro__(char *s, size_t len, const char *fmt, va_list ap)
 {
    int count = -1;
 
-   if (size != 0)
+   if (len != 0)
    {
 #if (_MSC_VER <= 1310)
-      count = _vsnprintf(outBuf, size - 1, format, ap);
+      count = _vsnprintf(s, len - 1, fmt, ap);
 #else
-      count = _vsnprintf_s(outBuf, size, size - 1, format, ap);
+      count = _vsnprintf_s(s, len, len - 1, fmt, ap);
 #endif
    }
 
    if (count == -1)
-       count = _vscprintf(format, ap);
+       count = _vscprintf(fmt, ap);
 
-   if (count == size)
-   {
-      /* there was no room for a NULL, so truncate the last character */
-      outBuf[size - 1] = '\0';
-   }
+   /* there was no room for a NULL, so truncate the last character */
+   if (count == len && len)
+      s[len - 1] = '\0';
 
    return count;
 }
 
-int c99_snprintf_retro__(char *outBuf, size_t size, const char *format, ...)
+int c99_snprintf_retro__(char *s, size_t len, const char *fmt, ...)
 {
    int count;
    va_list ap;
 
-   va_start(ap, format);
-   count = c99_vsnprintf_retro__(outBuf, size, format, ap);
+   va_start(ap, fmt);
+   count = c99_vsnprintf_retro__(s, len, fmt, ap);
    va_end(ap);
 
    return count;
diff --git a/src/drivers/libretro/libretro-common/compat/compat_strl.c b/src/drivers/libretro/libretro-common/compat/compat_strl.c
index 94cb39b..3172310 100644
--- a/src/drivers/libretro/libretro-common/compat/compat_strl.c
+++ b/src/drivers/libretro/libretro-common/compat/compat_strl.c
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (compat_strl.c).
diff --git a/src/drivers/libretro/libretro-common/encodings/encoding_utf.c b/src/drivers/libretro/libretro-common/encodings/encoding_utf.c
index b6ad2f9..2760824 100644
--- a/src/drivers/libretro/libretro-common/encodings/encoding_utf.c
+++ b/src/drivers/libretro/libretro-common/encodings/encoding_utf.c
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (encoding_utf.c).
@@ -37,6 +37,8 @@
 #include <xtl.h>
 #endif
 
+#define UTF8_WALKBYTE(string) (*((*(string))++))
+
 static unsigned leading_ones(uint8_t c)
 {
    unsigned ones = 0;
@@ -89,13 +91,14 @@ size_t utf8_conv_utf32(uint32_t *out, size_t out_chars,
 bool utf16_conv_utf8(uint8_t *out, size_t *out_chars,
      const uint16_t *in, size_t in_size)
 {
-   static uint8_t kUtf8Limits[5] = { 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
-   size_t out_pos = 0;
-   size_t in_pos  = 0;
+   size_t out_pos            = 0;
+   size_t in_pos             = 0;
+   static const 
+      uint8_t utf8_limits[5] = { 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
 
    for (;;)
    {
-      unsigned numAdds;
+      unsigned num_adds;
       uint32_t value;
 
       if (in_pos == in_size)
@@ -124,21 +127,21 @@ bool utf16_conv_utf8(uint8_t *out, size_t *out_chars,
          value = (((value - 0xD800) << 10) | (c2 - 0xDC00)) + 0x10000;
       }
 
-      for (numAdds = 1; numAdds < 5; numAdds++)
-         if (value < (((uint32_t)1) << (numAdds * 5 + 6)))
+      for (num_adds = 1; num_adds < 5; num_adds++)
+         if (value < (((uint32_t)1) << (num_adds * 5 + 6)))
             break;
       if (out)
-         out[out_pos] = (char)(kUtf8Limits[numAdds - 1]
-               + (value >> (6 * numAdds)));
+         out[out_pos] = (char)(utf8_limits[num_adds - 1]
+               + (value >> (6 * num_adds)));
       out_pos++;
       do
       {
-         numAdds--;
+         num_adds--;
          if (out)
             out[out_pos] = (char)(0x80
-                  + ((value >> (6 * numAdds)) & 0x3F));
+                  + ((value >> (6 * num_adds)) & 0x3F));
          out_pos++;
-      }while (numAdds != 0);
+      }while (num_adds != 0);
    }
 
    *out_chars = out_pos;
@@ -166,13 +169,15 @@ size_t utf8cpy(char *d, size_t d_len, const char *s, size_t chars)
    while (*sb && chars-- > 0)
    {
       sb++;
-      while ((*sb & 0xC0) == 0x80) sb++;
+      while ((*sb & 0xC0) == 0x80)
+         sb++;
    }
 
    if ((size_t)(sb - sb_org) > d_len-1 /* NUL */)
    {
       sb = sb_org + d_len-1;
-      while ((*sb & 0xC0) == 0x80) sb--;
+      while ((*sb & 0xC0) == 0x80)
+         sb--;
    }
 
    memcpy(d, sb_org, sb-sb_org);
@@ -184,14 +189,18 @@ size_t utf8cpy(char *d, size_t d_len, const char *s, size_t chars)
 const char *utf8skip(const char *str, size_t chars)
 {
    const uint8_t *strb = (const uint8_t*)str;
+
    if (!chars)
       return str;
+
    do
    {
       strb++;
-      while ((*strb & 0xC0)==0x80) strb++;
+      while ((*strb & 0xC0)==0x80)
+         strb++;
       chars--;
-   } while(chars);
+   }while (chars);
+
    return (const char*)strb;
 }
 
@@ -211,24 +220,22 @@ size_t utf8len(const char *string)
    return ret;
 }
 
-#define utf8_walkbyte(string) (*((*(string))++))
-
 /* Does not validate the input, returns garbage if it's not UTF-8. */
 uint32_t utf8_walk(const char **string)
 {
-   uint8_t first = utf8_walkbyte(string);
+   uint8_t first = UTF8_WALKBYTE(string);
    uint32_t ret  = 0;
 
    if (first < 128)
       return first;
 
-   ret    = (ret << 6) | (utf8_walkbyte(string) & 0x3F);
+   ret    = (ret << 6) | (UTF8_WALKBYTE(string) & 0x3F);
    if (first >= 0xE0)
    {
-      ret = (ret << 6) | (utf8_walkbyte(string) & 0x3F);
+      ret = (ret << 6) | (UTF8_WALKBYTE(string) & 0x3F);
       if (first >= 0xF0)
       {
-         ret = (ret << 6) | (utf8_walkbyte(string) & 0x3F);
+         ret = (ret << 6) | (UTF8_WALKBYTE(string) & 0x3F);
          return ret | (first & 7) << 18;
       }
       return ret | (first & 15) << 12;
@@ -277,9 +284,7 @@ bool utf16_to_char_string(const uint16_t *in, char *s, size_t len)
 static char *mb_to_mb_string_alloc(const char *str,
       enum CodePage cp_in, enum CodePage cp_out)
 {
-   char *path_buf         = NULL;
    wchar_t *path_buf_wide = NULL;
-   int path_buf_len       = 0;
    int path_buf_wide_len  = MultiByteToWideChar(cp_in, 0, str, -1, NULL, 0);
 
    /* Windows 95 will return 0 from these functions with 
@@ -292,54 +297,51 @@ static char *mb_to_mb_string_alloc(const char *str,
     *   MultiByteToWideChar also supports CP_UTF7 and CP_UTF8.
     */
 
-   if (path_buf_wide_len)
-   {
-      path_buf_wide = (wchar_t*)
-         calloc(path_buf_wide_len + sizeof(wchar_t), sizeof(wchar_t));
-
-      if (path_buf_wide)
-      {
-         MultiByteToWideChar(cp_in, 0,
-               str, -1, path_buf_wide, path_buf_wide_len);
-
-         if (*path_buf_wide)
-         {
-            path_buf_len = WideCharToMultiByte(cp_out, 0,
-                  path_buf_wide, -1, NULL, 0, NULL, NULL);
-
-            if (path_buf_len)
-            {
-               path_buf = (char*)
-                  calloc(path_buf_len + sizeof(char), sizeof(char));
-
-               if (path_buf)
-               {
-                  WideCharToMultiByte(cp_out, 0,
-                        path_buf_wide, -1, path_buf,
-                        path_buf_len, NULL, NULL);
-
-                  free(path_buf_wide);
-
-                  if (*path_buf)
-                     return path_buf;
-
-                  free(path_buf);
-                  return NULL;
-               }
-            }
-            else
-            {
-               free(path_buf_wide);
-               return strdup(str);
-            }
-         }
-      }
-   }
-   else
+   if (!path_buf_wide_len)
       return strdup(str);
 
+   path_buf_wide = (wchar_t*)
+      calloc(path_buf_wide_len + sizeof(wchar_t), sizeof(wchar_t));
+
    if (path_buf_wide)
+   {
+      MultiByteToWideChar(cp_in, 0,
+            str, -1, path_buf_wide, path_buf_wide_len);
+
+      if (*path_buf_wide)
+      {
+         int path_buf_len = WideCharToMultiByte(cp_out, 0,
+               path_buf_wide, -1, NULL, 0, NULL, NULL);
+
+         if (path_buf_len)
+         {
+            char *path_buf = (char*)
+               calloc(path_buf_len + sizeof(char), sizeof(char));
+
+            if (path_buf)
+            {
+               WideCharToMultiByte(cp_out, 0,
+                     path_buf_wide, -1, path_buf,
+                     path_buf_len, NULL, NULL);
+
+               free(path_buf_wide);
+
+               if (*path_buf)
+                  return path_buf;
+
+               free(path_buf);
+               return NULL;
+            }
+         }
+         else
+         {
+            free(path_buf_wide);
+            return strdup(str);
+         }
+      }
+
       free(path_buf_wide);
+   }
 
    return NULL;
 }
@@ -379,13 +381,13 @@ char* local_to_utf8_string_alloc(const char *str)
 wchar_t* utf8_to_utf16_string_alloc(const char *str)
 {
 #ifdef _WIN32
-   int len = 0;
-   int out_len = 0;
+   int len        = 0;
+   int out_len    = 0;
 #else
-   size_t len = 0;
+   size_t len     = 0;
    size_t out_len = 0;
 #endif
-   wchar_t *buf = NULL;
+   wchar_t *buf   = NULL;
 
    if (!str || !*str)
       return NULL;
diff --git a/src/drivers/libretro/libretro-common/include/boolean.h b/src/drivers/libretro/libretro-common/include/boolean.h
index f06ac5a..9d0d7c1 100644
--- a/src/drivers/libretro/libretro-common/include/boolean.h
+++ b/src/drivers/libretro/libretro-common/include/boolean.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (boolean.h).
diff --git a/src/drivers/libretro/libretro-common/include/compat/msvc.h b/src/drivers/libretro/libretro-common/include/compat/msvc.h
index 1c24263..a4c93a5 100644
--- a/src/drivers/libretro/libretro-common/include/compat/msvc.h
+++ b/src/drivers/libretro/libretro-common/include/compat/msvc.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (msvc.h).
@@ -29,22 +29,17 @@
 extern "C"  {
 #endif
 
-/* Pre-MSVC 2015 compilers don't implement snprintf in a cross-platform manner. */
+/* Pre-MSVC 2015 compilers don't implement snprintf, vsnprintf in a cross-platform manner. */
 #if _MSC_VER < 1900
-   #include <stdio.h>
-   #include <stdlib.h>
-   #ifndef snprintf
-      #define snprintf c99_snprintf_retro__
-   #endif
-
-   int c99_snprintf_retro__(char *outBuf, size_t size, const char *format, ...);
-#endif
-
-/* Pre-MSVC 2008 compilers don't implement vsnprintf in a cross-platform manner? Not sure about this one. */
-#if _MSC_VER < 1500
    #include <stdio.h>
    #include <stdarg.h>
    #include <stdlib.h>
+
+   #ifndef snprintf
+      #define snprintf c99_snprintf_retro__
+   #endif
+   int c99_snprintf_retro__(char *outBuf, size_t size, const char *format, ...);
+
    #ifndef vsnprintf
       #define vsnprintf c99_vsnprintf_retro__
    #endif
diff --git a/src/drivers/libretro/libretro-common/include/compat/strl.h b/src/drivers/libretro/libretro-common/include/compat/strl.h
index c70f119..5e7a892 100644
--- a/src/drivers/libretro/libretro-common/include/compat/strl.h
+++ b/src/drivers/libretro/libretro-common/include/compat/strl.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (strl.h).
diff --git a/src/drivers/libretro/libretro-common/include/encodings/crc32.h b/src/drivers/libretro/libretro-common/include/encodings/crc32.h
index 25e9262..5236c91 100644
--- a/src/drivers/libretro/libretro-common/include/encodings/crc32.h
+++ b/src/drivers/libretro/libretro-common/include/encodings/crc32.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (crc32.h).
diff --git a/src/drivers/libretro/libretro-common/include/encodings/utf.h b/src/drivers/libretro/libretro-common/include/encodings/utf.h
index b513f28..bea4e14 100644
--- a/src/drivers/libretro/libretro-common/include/encodings/utf.h
+++ b/src/drivers/libretro/libretro-common/include/encodings/utf.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (utf.h).
@@ -35,7 +35,7 @@ RETRO_BEGIN_DECLS
 enum CodePage
 {
    CODEPAGE_LOCAL = 0, /* CP_ACP */
-   CODEPAGE_UTF8 = 65001 /* CP_UTF8 */
+   CODEPAGE_UTF8  = 65001 /* CP_UTF8 */
 };
 
 size_t utf8_conv_utf32(uint32_t *out, size_t out_chars,
diff --git a/src/drivers/libretro/libretro-common/include/encodings/win32.h b/src/drivers/libretro/libretro-common/include/encodings/win32.h
index d4221bd..8104af0 100644
--- a/src/drivers/libretro/libretro-common/include/encodings/win32.h
+++ b/src/drivers/libretro/libretro-common/include/encodings/win32.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (utf.h).
diff --git a/src/drivers/libretro/libretro-common/include/libretro.h b/src/drivers/libretro/libretro-common/include/libretro.h
index 4ddb6e8..59bd513 100644
--- a/src/drivers/libretro/libretro-common/include/libretro.h
+++ b/src/drivers/libretro/libretro-common/include/libretro.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010-2018 The RetroArch team
+/* Copyright (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this libretro API header (libretro.h).
@@ -278,6 +278,10 @@ enum retro_language
    RETRO_LANGUAGE_ARABIC              = 16,
    RETRO_LANGUAGE_GREEK               = 17,
    RETRO_LANGUAGE_TURKISH             = 18,
+   RETRO_LANGUAGE_SLOVAK              = 19,
+   RETRO_LANGUAGE_PERSIAN             = 20,
+   RETRO_LANGUAGE_HEBREW              = 21,
+   RETRO_LANGUAGE_ASTURIAN            = 22,
    RETRO_LANGUAGE_LAST,
 
    /* Ensure sizeof(enum) == sizeof(int) */
@@ -1087,10 +1091,10 @@ enum retro_mod
 
 #define RETRO_ENVIRONMENT_GET_TARGET_REFRESH_RATE (50 | RETRO_ENVIRONMENT_EXPERIMENTAL)
                                             /* float * --
-                                            * Float value that lets us know what target refresh rate 
+                                            * Float value that lets us know what target refresh rate
                                             * is curently in use by the frontend.
                                             *
-                                            * The core can use the returned value to set an ideal 
+                                            * The core can use the returned value to set an ideal
                                             * refresh rate/framerate.
                                             */
 
@@ -1098,7 +1102,7 @@ enum retro_mod
                                             /* bool * --
                                             * Boolean value that indicates whether or not the frontend supports
                                             * input bitmasks being returned by retro_input_state_t. The advantage
-                                            * of this is that retro_input_state_t has to be only called once to 
+                                            * of this is that retro_input_state_t has to be only called once to
                                             * grab all button states instead of multiple times.
                                             *
                                             * If it returns true, you can pass RETRO_DEVICE_ID_JOYPAD_MASK as 'id'
@@ -1287,6 +1291,89 @@ enum retro_mod
                                             * based systems).
                                             */
 
+#define RETRO_ENVIRONMENT_GET_MESSAGE_INTERFACE_VERSION 59
+                                           /* unsigned * --
+                                            * Unsigned value is the API version number of the message
+                                            * interface supported by the frontend. If callback returns
+                                            * false, API version is assumed to be 0.
+                                            *
+                                            * In legacy code, messages may be displayed in an
+                                            * implementation-specific manner by passing a struct
+                                            * of type retro_message to RETRO_ENVIRONMENT_SET_MESSAGE.
+                                            * This may be still be done regardless of the message
+                                            * interface version.
+                                            *
+                                            * If version is >= 1 however, messages may instead be
+                                            * displayed by passing a struct of type retro_message_ext
+                                            * to RETRO_ENVIRONMENT_SET_MESSAGE_EXT. This allows the
+                                            * core to specify message logging level, priority and
+                                            * destination (OSD, logging interface or both).
+                                            */
+
+#define RETRO_ENVIRONMENT_SET_MESSAGE_EXT 60
+                                           /* const struct retro_message_ext * --
+                                            * Sets a message to be displayed in an implementation-specific
+                                            * manner for a certain amount of 'frames'. Additionally allows
+                                            * the core to specify message logging level, priority and
+                                            * destination (OSD, logging interface or both).
+                                            * Should not be used for trivial messages, which should simply be
+                                            * logged via RETRO_ENVIRONMENT_GET_LOG_INTERFACE (or as a
+                                            * fallback, stderr).
+                                            */
+
+#define RETRO_ENVIRONMENT_GET_INPUT_MAX_USERS 61
+                                           /* unsigned * --
+                                            * Unsigned value is the number of active input devices
+                                            * provided by the frontend. This may change between
+                                            * frames, but will remain constant for the duration
+                                            * of each frame.
+                                            * If callback returns true, a core need not poll any
+                                            * input device with an index greater than or equal to
+                                            * the number of active devices.
+                                            * If callback returns false, the number of active input
+                                            * devices is unknown. In this case, all input devices
+                                            * should be considered active.
+                                            */
+
+#define RETRO_ENVIRONMENT_SET_AUDIO_BUFFER_STATUS_CALLBACK 62
+                                           /* const struct retro_audio_buffer_status_callback * --
+                                            * Lets the core know the occupancy level of the frontend
+                                            * audio buffer. Can be used by a core to attempt frame
+                                            * skipping in order to avoid buffer under-runs.
+                                            * A core may pass NULL to disable buffer status reporting
+                                            * in the frontend.
+                                            */
+
+#define RETRO_ENVIRONMENT_SET_MINIMUM_AUDIO_LATENCY 63
+                                           /* const unsigned * --
+                                            * Sets minimum frontend audio latency in milliseconds.
+                                            * Resultant audio latency may be larger than set value,
+                                            * or smaller if a hardware limit is encountered. A frontend
+                                            * is expected to honour requests up to 512 ms.
+                                            *
+                                            * - If value is less than current frontend
+                                            *   audio latency, callback has no effect
+                                            * - If value is zero, default frontend audio
+                                            *   latency is set
+                                            *
+                                            * May be used by a core to increase audio latency and
+                                            * therefore decrease the probability of buffer under-runs
+                                            * (crackling) when performing 'intensive' operations.
+                                            * A core utilising RETRO_ENVIRONMENT_SET_AUDIO_BUFFER_STATUS_CALLBACK
+                                            * to implement audio-buffer-based frame skipping may achieve
+                                            * optimal results by setting the audio latency to a 'high'
+                                            * (typically 6x or 8x) integer multiple of the expected
+                                            * frame time.
+                                            *
+                                            * WARNING: This can only be called from within retro_run().
+                                            * Calling this can require a full reinitialization of audio
+                                            * drivers in the frontend, so it is important to call it very
+                                            * sparingly, and usually only with the users explicit consent.
+                                            * An eventual driver reinitialize will happen so that audio
+                                            * callbacks happening after this call within the same retro_run()
+                                            * call will target the newly initialized driver.
+                                            */
+
 /* VFS functionality */
 
 /* File paths:
@@ -2176,6 +2263,30 @@ struct retro_frame_time_callback
    retro_usec_t reference;
 };
 
+/* Notifies a libretro core of the current occupancy
+ * level of the frontend audio buffer.
+ *
+ * - active: 'true' if audio buffer is currently
+ *           in use. Will be 'false' if audio is
+ *           disabled in the frontend
+ *
+ * - occupancy: Given as a value in the range [0,100],
+ *              corresponding to the occupancy percentage
+ *              of the audio buffer
+ *
+ * - underrun_likely: 'true' if the frontend expects an
+ *                    audio buffer underrun during the
+ *                    next frame (indicates that a core
+ *                    should attempt frame skipping)
+ *
+ * It will be called right before retro_run() every frame. */
+typedef void (RETRO_CALLCONV *retro_audio_buffer_status_callback_t)(
+      bool active, unsigned occupancy, bool underrun_likely);
+struct retro_audio_buffer_status_callback
+{
+   retro_audio_buffer_status_callback_t callback;
+};
+
 /* Pass this to retro_video_refresh_t if rendering to hardware.
  * Passing NULL to retro_video_refresh_t is still a frame dupe as normal.
  * */
@@ -2506,6 +2617,104 @@ struct retro_message
    unsigned    frames;     /* Duration in frames of message. */
 };
 
+enum retro_message_target
+{
+   RETRO_MESSAGE_TARGET_ALL = 0,
+   RETRO_MESSAGE_TARGET_OSD,
+   RETRO_MESSAGE_TARGET_LOG
+};
+
+enum retro_message_type
+{
+   RETRO_MESSAGE_TYPE_NOTIFICATION = 0,
+   RETRO_MESSAGE_TYPE_NOTIFICATION_ALT,
+   RETRO_MESSAGE_TYPE_STATUS,
+   RETRO_MESSAGE_TYPE_PROGRESS
+};
+
+struct retro_message_ext
+{
+   /* Message string to be displayed/logged */
+   const char *msg;
+   /* Duration (in ms) of message when targeting the OSD */
+   unsigned duration;
+   /* Message priority when targeting the OSD
+    * > When multiple concurrent messages are sent to
+    *   the frontend and the frontend does not have the
+    *   capacity to display them all, messages with the
+    *   *highest* priority value should be shown
+    * > There is no upper limit to a message priority
+    *   value (within the bounds of the unsigned data type)
+    * > In the reference frontend (RetroArch), the same
+    *   priority values are used for frontend-generated
+    *   notifications, which are typically assigned values
+    *   between 0 and 3 depending upon importance */
+   unsigned priority;
+   /* Message logging level (info, warn, error, etc.) */
+   enum retro_log_level level;
+   /* Message destination: OSD, logging interface or both */
+   enum retro_message_target target;
+   /* Message 'type' when targeting the OSD
+    * > RETRO_MESSAGE_TYPE_NOTIFICATION: Specifies that a
+    *   message should be handled in identical fashion to
+    *   a standard frontend-generated notification
+    * > RETRO_MESSAGE_TYPE_NOTIFICATION_ALT: Specifies that
+    *   message is a notification that requires user attention
+    *   or action, but that it should be displayed in a manner
+    *   that differs from standard frontend-generated notifications.
+    *   This would typically correspond to messages that should be
+    *   displayed immediately (independently from any internal
+    *   frontend message queue), and/or which should be visually
+    *   distinguishable from frontend-generated notifications.
+    *   For example, a core may wish to inform the user of
+    *   information related to a disk-change event. It is
+    *   expected that the frontend itself may provide a
+    *   notification in this case; if the core sends a
+    *   message of type RETRO_MESSAGE_TYPE_NOTIFICATION, an
+    *   uncomfortable 'double-notification' may occur. A message
+    *   of RETRO_MESSAGE_TYPE_NOTIFICATION_ALT should therefore
+    *   be presented such that visual conflict with regular
+    *   notifications does not occur
+    * > RETRO_MESSAGE_TYPE_STATUS: Indicates that message
+    *   is not a standard notification. This typically
+    *   corresponds to 'status' indicators, such as a core's
+    *   internal FPS, which are intended to be displayed
+    *   either permanently while a core is running, or in
+    *   a manner that does not suggest user attention or action
+    *   is required. 'Status' type messages should therefore be
+    *   displayed in a different on-screen location and in a manner
+    *   easily distinguishable from both standard frontend-generated
+    *   notifications and messages of type RETRO_MESSAGE_TYPE_NOTIFICATION_ALT
+    * > RETRO_MESSAGE_TYPE_PROGRESS: Indicates that message reports
+    *   the progress of an internal core task. For example, in cases
+    *   where a core itself handles the loading of content from a file,
+    *   this may correspond to the percentage of the file that has been
+    *   read. Alternatively, an audio/video playback core may use a
+    *   message of type RETRO_MESSAGE_TYPE_PROGRESS to display the current
+    *   playback position as a percentage of the runtime. 'Progress' type
+    *   messages should therefore be displayed as a literal progress bar,
+    *   where:
+    *   - 'retro_message_ext.msg' is the progress bar title/label
+    *   - 'retro_message_ext.progress' determines the length of
+    *     the progress bar
+    * NOTE: Message type is a *hint*, and may be ignored
+    * by the frontend. If a frontend lacks support for
+    * displaying messages via alternate means than standard
+    * frontend-generated notifications, it will treat *all*
+    * messages as having the type RETRO_MESSAGE_TYPE_NOTIFICATION */
+   enum retro_message_type type;
+   /* Task progress when targeting the OSD and message is
+    * of type RETRO_MESSAGE_TYPE_PROGRESS
+    * > -1:    Unmetered/indeterminate
+    * > 0-100: Current progress percentage
+    * NOTE: Since message type is a hint, a frontend may ignore
+    * progress values. Where relevant, a core should therefore
+    * include progress percentage within the message string,
+    * such that the message intent remains clear when displayed
+    * as a standard frontend-generated notification */
+   int8_t progress;
+};
+
 /* Describes how the libretro implementation maps a libretro input bind
  * to its internal input system through a human readable string.
  * This string can be used to better let a user configure input. */
@@ -2526,7 +2735,7 @@ struct retro_input_descriptor
 struct retro_system_info
 {
    /* All pointers are owned by libretro implementation, and pointers must
-    * remain valid until retro_deinit() is called. */
+    * remain valid until it is unloaded. */
 
    const char *library_name;      /* Descriptive name of library. Should not
                                    * contain any version numbers, etc. */
diff --git a/src/drivers/libretro/libretro-common/include/retro_common.h b/src/drivers/libretro/libretro-common/include/retro_common.h
index 9a1fd5f..a715a28 100644
--- a/src/drivers/libretro/libretro-common/include/retro_common.h
+++ b/src/drivers/libretro/libretro-common/include/retro_common.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (retro_common.h).
diff --git a/src/drivers/libretro/libretro-common/include/retro_common_api.h b/src/drivers/libretro/libretro-common/include/retro_common_api.h
index d784842..0f68b7d 100644
--- a/src/drivers/libretro/libretro-common/include/retro_common_api.h
+++ b/src/drivers/libretro/libretro-common/include/retro_common_api.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (retro_common_api.h).
diff --git a/src/drivers/libretro/libretro-common/include/retro_inline.h b/src/drivers/libretro/libretro-common/include/retro_inline.h
index e4a21f6..b27d6dd 100644
--- a/src/drivers/libretro/libretro-common/include/retro_inline.h
+++ b/src/drivers/libretro/libretro-common/include/retro_inline.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (retro_inline.h).
diff --git a/src/drivers/libretro/libretro-common/include/streams/memory_stream.h b/src/drivers/libretro/libretro-common/include/streams/memory_stream.h
index f9e641b..2c6f3fc 100644
--- a/src/drivers/libretro/libretro-common/include/streams/memory_stream.h
+++ b/src/drivers/libretro/libretro-common/include/streams/memory_stream.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (memory_stream.h).
diff --git a/src/drivers/libretro/libretro-common/include/string/stdstring.h b/src/drivers/libretro/libretro-common/include/string/stdstring.h
index d57256a..5d8c31b 100644
--- a/src/drivers/libretro/libretro-common/include/string/stdstring.h
+++ b/src/drivers/libretro/libretro-common/include/string/stdstring.h
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2019 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (stdstring.h).
@@ -35,6 +35,33 @@
 
 RETRO_BEGIN_DECLS
 
+#define STRLEN_CONST(x)                   ((sizeof((x))-1))
+
+#define strcpy_literal(a, b)              strcpy(a, b)
+
+#define string_is_not_equal(a, b)         !string_is_equal((a), (b))
+
+#define string_is_not_equal_fast(a, b, size) (memcmp(a, b, size) != 0)
+#define string_is_equal_fast(a, b, size)     (memcmp(a, b, size) == 0)
+
+#define TOLOWER(c)   (c |  (lr_char_props[c] & 0x20))
+#define TOUPPER(c)   (c & ~(lr_char_props[c] & 0x20))
+
+/* C standard says \f \v are space, but this one disagrees */
+#define ISSPACE(c)   (lr_char_props[c]  & 0x80) 
+
+#define ISDIGIT(c)   (lr_char_props[c]  & 0x40)
+#define ISALPHA(c)   (lr_char_props[c]  & 0x20)
+#define ISLOWER(c)   (lr_char_props[c]  & 0x04)
+#define ISUPPER(c)   (lr_char_props[c]  & 0x02)
+#define ISALNUM(c)   (lr_char_props[c]  & 0x60)
+#define ISUALPHA(c)  (lr_char_props[c]  & 0x28)
+#define ISUALNUM(c)  (lr_char_props[c]  & 0x68)
+#define IS_XDIGIT(c) (lr_char_props[c]  & 0x01)
+
+/* Deprecated alias, all callers should use string_is_equal_case_insensitive instead */
+#define string_is_equal_noncase string_is_equal_case_insensitive
+
 static INLINE bool string_is_empty(const char *data)
 {
    return !data || (*data == '\0');
@@ -45,12 +72,44 @@ static INLINE bool string_is_equal(const char *a, const char *b)
    return (a && b) ? !strcmp(a, b) : false;
 }
 
-#define STRLEN_CONST(x)                   ((sizeof((x))-1))
+static INLINE bool string_starts_with_size(const char *str, const char *prefix,
+      size_t size)
+{
+   return (str && prefix) ? !strncmp(prefix, str, size) : false;
+}
 
-#define string_is_not_equal(a, b)         !string_is_equal((a), (b))
+static INLINE bool string_starts_with(const char *str, const char *prefix)
+{
+   return (str && prefix) ? !strncmp(prefix, str, strlen(prefix)) : false;
+}
+
+static INLINE bool string_ends_with_size(const char *str, const char *suffix,
+      size_t str_len, size_t suffix_len)
+{
+   return (str_len < suffix_len) ? false :
+         !memcmp(suffix, str + (str_len - suffix_len), suffix_len);
+}
+
+static INLINE bool string_ends_with(const char *str, const char *suffix)
+{
+   if (!str || !suffix)
+      return false;
+   return string_ends_with_size(str, suffix, strlen(str), strlen(suffix));
+}
+
+/* Returns the length of 'str' (c.f. strlen()), but only
+ * checks the first 'size' characters
+ * - If 'str' is NULL, returns 0
+ * - If 'str' is not NULL and no '\0' character is found
+ *   in the first 'size' characters, returns 'size' */
+static INLINE size_t strlen_size(const char *str, size_t size)
+{
+   size_t i = 0;
+   if (str)
+      while (i < size && str[i]) i++;
+   return i;
+}
 
-#define string_is_not_equal_fast(a, b, size) (memcmp(a, b, size) != 0)
-#define string_is_equal_fast(a, b, size)     (memcmp(a, b, size) == 0)
 
 static INLINE bool string_is_equal_case_insensitive(const char *a,
       const char *b)
@@ -71,24 +130,6 @@ static INLINE bool string_is_equal_case_insensitive(const char *a,
    return (result == 0);
 }
 
-static INLINE bool string_is_equal_noncase(const char *a, const char *b)
-{
-   int result              = 0;
-   const unsigned char *p1 = (const unsigned char*)a;
-   const unsigned char *p2 = (const unsigned char*)b;
-
-   if (!a || !b)
-      return false;
-   if (p1 == p2)
-      return false;
-
-   while ((result = tolower (*p1) - tolower (*p2++)) == 0)
-      if (*p1++ == '\0')
-         break;
-
-   return (result == 0);
-}
-
 char *string_to_upper(char *s);
 
 char *string_to_lower(char *s);
@@ -121,7 +162,7 @@ char *word_wrap(char *buffer, const char *string,
  *    char *str      = "1,2,3,4,5,6,7,,,10,";
  *    char **str_ptr = &str;
  *    char *token    = NULL;
- *    while((token = string_tokenize(str_ptr, ",")))
+ *    while ((token = string_tokenize(str_ptr, ",")))
  *    {
  *        printf("%s\n", token);
  *        free(token);
@@ -146,6 +187,12 @@ unsigned string_to_unsigned(const char *str);
  * Returns 0 if string is invalid  */
 unsigned string_hex_to_unsigned(const char *str);
 
+char *string_init(const char *src);
+
+void string_set(char **string, const char *src);
+
+extern const unsigned char lr_char_props[256];
+
 RETRO_END_DECLS
 
 #endif
diff --git a/src/drivers/libretro/libretro-common/streams/memory_stream.c b/src/drivers/libretro/libretro-common/streams/memory_stream.c
index 829ef03..2aa1c80 100644
--- a/src/drivers/libretro/libretro-common/streams/memory_stream.c
+++ b/src/drivers/libretro/libretro-common/streams/memory_stream.c
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (memory_stream.c).
@@ -26,29 +26,24 @@
 
 #include <streams/memory_stream.h>
 
+/* TODO/FIXME - static globals */
 static uint8_t* g_buffer      = NULL;
 static uint64_t g_size         = 0;
 static uint64_t last_file_size = 0;
 
 struct memstream
 {
-   uint8_t *buf;
    uint64_t size;
    uint64_t ptr;
    uint64_t max_ptr;
+   uint8_t *buf;
    unsigned writing;
 };
 
-static void memstream_update_pos(memstream_t *stream)
-{
-   if (stream && stream->ptr > stream->max_ptr)
-      stream->max_ptr = stream->ptr;
-}
-
 void memstream_set_buffer(uint8_t *buffer, uint64_t size)
 {
    g_buffer = buffer;
-   g_size = size;
+   g_size   = size;
 }
 
 uint64_t memstream_get_last_size(void)
@@ -56,30 +51,26 @@ uint64_t memstream_get_last_size(void)
    return last_file_size;
 }
 
-static void memstream_init(memstream_t *stream,
-      uint8_t *buffer, uint64_t max_size, unsigned writing)
-{
-   if (!stream)
-      return;
-
-   stream->buf     = buffer;
-   stream->size    = max_size;
-   stream->ptr     = 0;
-   stream->max_ptr = 0;
-   stream->writing = writing;
-}
-
 memstream_t *memstream_open(unsigned writing)
 {
    memstream_t *stream;
    if (!g_buffer || !g_size)
       return NULL;
 
-   stream = (memstream_t*)calloc(1, sizeof(*stream));
-   memstream_init(stream, g_buffer, g_size, writing);
+   stream = (memstream_t*)malloc(sizeof(*stream));
+
+   if (!stream)
+      return NULL;
+
+   stream->buf       = g_buffer;
+   stream->size      = g_size;
+   stream->ptr       = 0;
+   stream->max_ptr   = 0;
+   stream->writing   = writing;
+
+   g_buffer          = NULL;
+   g_size            = 0;
 
-   g_buffer = NULL;
-   g_size = 0;
    return stream;
 }
 
@@ -104,17 +95,19 @@ uint64_t memstream_read(memstream_t *stream, void *data, uint64_t bytes)
    if (!stream)
       return 0;
 
-   avail = stream->size - stream->ptr;
+   avail               = stream->size - stream->ptr;
    if (bytes > avail)
-      bytes = avail;
+      bytes            = avail;
 
    memcpy(data, stream->buf + stream->ptr, (size_t)bytes);
-   stream->ptr += bytes;
-   memstream_update_pos(stream);
+   stream->ptr        += bytes;
+   if (stream->ptr > stream->max_ptr)
+      stream->max_ptr  = stream->ptr;
    return bytes;
 }
 
-uint64_t memstream_write(memstream_t *stream, const void *data, uint64_t bytes)
+uint64_t memstream_write(memstream_t *stream,
+      const void *data, uint64_t bytes)
 {
    uint64_t avail = 0;
 
@@ -127,7 +120,8 @@ uint64_t memstream_write(memstream_t *stream, const void *data, uint64_t bytes)
 
    memcpy(stream->buf + stream->ptr, data, (size_t)bytes);
    stream->ptr += bytes;
-   memstream_update_pos(stream);
+   if (stream->ptr > stream->max_ptr)
+      stream->max_ptr = stream->ptr;
    return bytes;
 }
 
@@ -181,7 +175,8 @@ int memstream_getc(memstream_t *stream)
       return EOF;
    ret = stream->buf[stream->ptr++];
 
-   memstream_update_pos(stream);
+   if (stream->ptr > stream->max_ptr)
+      stream->max_ptr = stream->ptr;
 
    return ret;
 }
@@ -191,5 +186,6 @@ void memstream_putc(memstream_t *stream, int c)
    if (stream->ptr < stream->size)
       stream->buf[stream->ptr++] = c;
 
-   memstream_update_pos(stream);
+   if (stream->ptr > stream->max_ptr)
+      stream->max_ptr = stream->ptr;
 }
diff --git a/src/drivers/libretro/libretro-common/string/stdstring.c b/src/drivers/libretro/libretro-common/string/stdstring.c
index e2afef1..67ee7fc 100644
--- a/src/drivers/libretro/libretro-common/string/stdstring.c
+++ b/src/drivers/libretro/libretro-common/string/stdstring.c
@@ -1,4 +1,4 @@
-/* Copyright  (C) 2010-2018 The RetroArch team
+/* Copyright  (C) 2010-2020 The RetroArch team
  *
  * ---------------------------------------------------------------------------------------
  * The following license statement only applies to this file (stdstring.c).
@@ -22,10 +22,43 @@
 
 #include <stdint.h>
 #include <ctype.h>
+#include <string.h>
 
 #include <string/stdstring.h>
 #include <encodings/utf.h>
 
+const uint8_t lr_char_props[256] = {
+	/*x0   x1   x2   x3   x4   x5   x6   x7   x8   x9   xA   xB   xC   xD   xE   xF */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x80,0x00,0x00,0x80,0x00,0x00, /* 0x                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 1x                  */
+	0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 2x  !"#$%&'()*+,-./ */
+	0x41,0x41,0x41,0x41,0x41,0x41,0x41,0x41,0x41,0x41,0x00,0x00,0x00,0x00,0x00,0x00, /* 3x 0123456789:;<=>? */
+	0x00,0x23,0x23,0x23,0x23,0x23,0x23,0x22,0x22,0x22,0x22,0x22,0x22,0x22,0x22,0x22, /* 4x @ABCDEFGHIJKLMNO */
+	0x22,0x22,0x22,0x22,0x22,0x22,0x22,0x22,0x22,0x22,0x22,0x00,0x00,0x00,0x00,0x08, /* 5x PQRSTUVWXYZ[\]^_ */
+	0x00,0x25,0x25,0x25,0x25,0x25,0x25,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24, /* 6x `abcdefghijklmno */
+	0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x00,0x00,0x00,0x00,0x00, /* 7x pqrstuvwxyz{|}~  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 8x                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 9x                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Ax                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Bx                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Cx                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Dx                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Ex                  */
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Fx                  */
+};
+
+char *string_init(const char *src)
+{
+   return src ? strdup(src) : NULL;
+}
+
+void string_set(char **string, const char *src)
+{
+   free(*string);
+   *string = string_init(src);
+}
+
+
 char *string_to_upper(char *s)
 {
    char *cs = (char *)s;
@@ -107,18 +140,18 @@ char *string_replace_substring(const char *in,
 /* Remove leading whitespaces */
 char *string_trim_whitespace_left(char *const s)
 {
-   if(s && *s)
+   if (s && *s)
    {
       size_t len     = strlen(s);
       char *current  = s;
 
-      while(*current && isspace((unsigned char)*current))
+      while (*current && ISSPACE((unsigned char)*current))
       {
          ++current;
          --len;
       }
 
-      if(s != current)
+      if (s != current)
          memmove(s, current, len + 1);
    }
 
@@ -128,18 +161,18 @@ char *string_trim_whitespace_left(char *const s)
 /* Remove trailing whitespaces */
 char *string_trim_whitespace_right(char *const s)
 {
-   if(s && *s)
+   if (s && *s)
    {
       size_t len     = strlen(s);
       char  *current = s + len - 1;
 
-      while(current != s && isspace((unsigned char)*current))
+      while (current != s && ISSPACE((unsigned char)*current))
       {
          --current;
          --len;
       }
 
-      current[isspace((unsigned char)*current) ? 0 : 1] = '\0';
+      current[ISSPACE((unsigned char)*current) ? 0 : 1] = '\0';
    }
 
    return s;
@@ -190,7 +223,7 @@ char *word_wrap(char* buffer, const char *string, int line_width, bool unicode,
             buffer[i] = string[i];
             char_len--;
             i++;
-         } while(char_len);
+         } while (char_len);
 
          /* check for newlines embedded in the original input
           * and reset the index */
@@ -248,7 +281,7 @@ char *word_wrap(char* buffer, const char *string, int line_width, bool unicode,
  *    char *str      = "1,2,3,4,5,6,7,,,10,";
  *    char **str_ptr = &str;
  *    char *token    = NULL;
- *    while((token = string_tokenize(str_ptr, ",")))
+ *    while ((token = string_tokenize(str_ptr, ",")))
  *    {
  *        printf("%s\n", token);
  *        free(token);
@@ -328,7 +361,7 @@ void string_replace_all_chars(char *str, char find, char replace)
    if (string_is_empty(str))
       return;
 
-   while((str_ptr = strchr(str_ptr, find)) != NULL)
+   while ((str_ptr = strchr(str_ptr, find)))
       *str_ptr++ = replace;
 }
 
@@ -343,7 +376,7 @@ unsigned string_to_unsigned(const char *str)
 
    for (ptr = str; *ptr != '\0'; ptr++)
    {
-      if (!isdigit(*ptr))
+      if (!ISDIGIT((unsigned char)*ptr))
          return 0;
    }
 
@@ -376,7 +409,7 @@ unsigned string_hex_to_unsigned(const char *str)
    /* Check for valid characters */
    for (ptr = hex_str; *ptr != '\0'; ptr++)
    {
-      if (!isxdigit(*ptr))
+      if (!isxdigit((unsigned char)*ptr))
          return 0;
    }
 
diff --git a/src/drivers/libretro/libretro.c b/src/drivers/libretro/libretro.c
index 7e5b6fb..43536b6 100644
--- a/src/drivers/libretro/libretro.c
+++ b/src/drivers/libretro/libretro.c
@@ -1046,7 +1046,7 @@ static void retro_set_custom_palette(void)
  * Dendy has PAL framerate and resolution, but ~NTSC timings,
  * and has 50 dummy scanlines to force 50 fps.
  */
-void FCEUD_RegionOverride(unsigned region)
+static void FCEUD_RegionOverride(unsigned region)
 {
    unsigned pal = 0;
    unsigned d = 0;
@@ -1071,8 +1071,6 @@ void FCEUD_RegionOverride(unsigned region)
    }
 
    dendy = d;
-   normal_scanlines = dendy ? 290 : 240;
-   totalscanlines = normal_scanlines + (overclock_enabled ? extrascanlines : 0);
    FCEUI_SetVidSystem(pal);
    ResetPalette();
 }
@@ -1116,7 +1114,6 @@ static void set_apu_channels(int chan)
 static void check_variables(bool startup)
 {
    struct retro_variable var = {0};
-   bool palette_updated = false;
    char key[256];
    int i, enable_apu;
 
@@ -1879,9 +1876,8 @@ static void retro_run_blit(uint8_t *gfx)
 
 void retro_run(void)
 {
-   unsigned i;
    uint8_t *gfx;
-   int32_t ssize = 0;
+   int32_t i, ssize = 0;
    bool updated = false;
 
    if (environ_cb(RETRO_ENVIRONMENT_GET_VARIABLE_UPDATE, &updated) && updated)
@@ -1948,7 +1944,7 @@ static int checkGG(char c)
 static int GGisvalid(const char *code)
 {
    size_t len = strlen(code);
-   int i;
+   uint32 i;
    
    if (len != 6 && len != 8)
       return 0;
@@ -1973,7 +1969,6 @@ void retro_cheat_set(unsigned index, bool enabled, const char *code)
    uint8  v;
    int    c;
    int    type = 1;
-   int    ret = 0;
 
    if (code == NULL)
       return;
diff --git a/src/general.c b/src/general.c
index 70321ab..33af07f 100644
--- a/src/general.c
+++ b/src/general.c
@@ -69,22 +69,22 @@ void FCEUI_SetDirOverride(int which, char *n)
 
 char *FCEU_MakeFName(int type, int id1, char *cd1)
 {
-   char tmp[2048] = {0};
+   char tmp[4096 + 512] = {0}; /* +512 for no reason :D */
    char *ret      = 0;
 
    switch (type)
    {
       case FCEUMKF_GGROM:
-         sprintf(tmp, "%s"PSS "gg.rom", BaseDirectory);
+         sprintf(tmp, "%s%c%s", BaseDirectory, PS, "gg.rom");
          break;
       case FCEUMKF_FDSROM:
-         sprintf(tmp, "%s"PSS "disksys.rom", BaseDirectory);
+         sprintf(tmp, "%s%c%s", BaseDirectory, PS, "disksys.rom");
          break;
       case FCEUMKF_PALETTE:
-         sprintf(tmp, "%s"PSS "nes.pal", BaseDirectory);
+         sprintf(tmp, "%s%c%s", BaseDirectory, PS, "nes.pal");
          break;
       case FCEUMKF_FDS:
-         sprintf(tmp, "%s"PSS "%s.sav", SaveDirectory, FileBase);
+         sprintf(tmp, "%s%c%s%s", SaveDirectory, PS, FileBase, ".sav");
          break;
       default:
          break;
diff --git a/src/input/shadow.c b/src/input/shadow.c
index 8f9d767..e8b0aa9 100644
--- a/src/input/shadow.c
+++ b/src/input/shadow.c
@@ -66,7 +66,7 @@ static void FP_FASTAPASS(3) ZapperFrapper(uint8 * bg, uint8 * spr, uint32 linets
 
 				sum = palo[a1].r + palo[a1].g + palo[a1].b;
 				if (sum >= 100 * 3) {
-					ZD.zaphit = ((uint64)linets + (xs + 16) * (PAL ? 15 : 16)) / 48 + timestampbase;
+					ZD.zaphit = ((uint64)linets + (uint64)(xs + 16) * (PAL ? 15 : 16)) / 48 + timestampbase;
 					goto endo;
 				}
 			}
diff --git a/src/input/zapper.c b/src/input/zapper.c
index 776f51a..3d891f4 100644
--- a/src/input/zapper.c
+++ b/src/input/zapper.c
@@ -28,7 +28,7 @@
 #define MAX_TOLERANCE 20
 static uint32 targetExpansion[MAX_TOLERANCE+1];
 #endif
-static int tolerance;
+static uint32 tolerance;
 
 typedef struct {
 	uint32 mzx, mzy, mzb;
@@ -82,7 +82,7 @@ static void FP_FASTAPASS(3) ZapperFrapper(int w, uint8 * bg, uint8 * spr, uint32
 
 				sum = palo[a1].r + palo[a1].g + palo[a1].b;
 				if (sum >= 100 * 3) {
-					ZD[w].zaphit = ((uint64)linets + (xs + 16) * (PAL ? 15 : 16)) / 48 + timestampbase;
+					ZD[w].zaphit = ((uint64)linets + (uint64)(xs + 16) * (PAL ? 15 : 16)) / 48 + timestampbase;
 					goto endo;
 				}
 			}
@@ -167,7 +167,7 @@ static uint32 InefficientSqrt(uint32 z) {
 void FCEU_ZapperSetTolerance(int t)
 {
 #ifdef ROUNDED_TARGET
-	uint32_t y;
+	uint32 y;
 	tolerance = t <= MAX_TOLERANCE ? t : MAX_TOLERANCE;
 	for (y = 0; y <= tolerance; y++)
 		targetExpansion[y] = InefficientSqrt(tolerance*tolerance-y*y);
diff --git a/src/sound.c b/src/sound.c
index 40973c2..2fd2ca2 100644
--- a/src/sound.c
+++ b/src/sound.c
@@ -195,6 +195,8 @@ static DECLFW(Write_PSG) {
 		DoSQ1();
 		EnvUnits[0].Mode = (V & 0x30) >> 4;
 		EnvUnits[0].Speed = (V & 0xF);
+		if (swapDuty)
+			V = (V & 0x3F) | ((V & 0x80) >> 1) | ((V & 0x40) << 1);
 		break;
 	case 0x1:
 		DoSQ1();
@@ -214,6 +216,8 @@ static DECLFW(Write_PSG) {
 		DoSQ2();
 		EnvUnits[1].Mode = (V & 0x30) >> 4;
 		EnvUnits[1].Speed = (V & 0xF);
+		if (swapDuty)
+			V = (V & 0x3F) | ((V & 0x80) >> 1) | ((V & 0x40) << 1);
 		break;
 	case 0x5:
 		DoSQ2();
@@ -561,8 +565,6 @@ static INLINE void RDoSQ(int x) {
 
 		amp <<= 24;
 		dutyCycle = (PSG[(x << 2)] & 0xC0) >> 6;
-		if (swapDuty)
-			dutyCycle = ((dutyCycle & 2) >> 1) | ((dutyCycle & 1) << 1);
 		rthresh = RectDuties[dutyCycle];
 		currdc = RectDutyCount[x];
 		D = &WaveHi[ChannelBC[x]];
@@ -640,8 +642,6 @@ static void RDoSQLQ(void) {
 		if (!inie[x]) amp[x] = 0;	/* Correct? Buzzing in MM2, others otherwise... */
 
 		dutyCycle = (PSG[(x << 2)] & 0xC0) >> 6;
-		if (swapDuty)
-			dutyCycle = ((dutyCycle & 2) >> 1) | ((dutyCycle & 1) << 1);
 		rthresh[x] = RectDuties[dutyCycle];
 
 		for (y = 0; y < 8; y++) {
@@ -1254,7 +1254,7 @@ void FCEUSND_LoadState(int version) {
 	/* minimal validation */
 	for (i = 0; i < 5; i++)
 	{
-		int BC_max = 15;
+		uint32 BC_max = 15;
 
 		if (FSettings.soundq == 2)
 		{
@@ -1264,7 +1264,7 @@ void FCEUSND_LoadState(int version) {
 		{
 			BC_max = 485;
 		}
-		if (ChannelBC[i] < 0 || ChannelBC[i] > BC_max)
+		if (/* ChannelBC[i] < 0 || */ ChannelBC[i] > BC_max)
 		{
 			ChannelBC[i] = 0;
 		}
@@ -1283,14 +1283,16 @@ void FCEUSND_LoadState(int version) {
 			RectDutyCount[i] = 7;
 		}
 	}
-	if (sound_timestamp < 0)
+
+	/* Comparison is always false because access to array >= 0. */
+	/* if (sound_timestamp < 0)
 	{
 		sound_timestamp = 0;
 	}
 	if (soundtsoffs < 0)
 	{
 		soundtsoffs = 0;
-	}
+	} */
 	if (soundtsoffs + sound_timestamp >= soundtsinc)
 	{
 		soundtsoffs = 0;
diff --git a/src/state.c b/src/state.c
index baeab1c..1c14a8d 100644
--- a/src/state.c
+++ b/src/state.c
@@ -85,7 +85,7 @@ static int SubWrite(memstream_t *mem, SFORMAT *sf)
 
    while(sf->v)
    {
-      if(sf->s == ~0) /* Link to another struct. */
+      if(sf->s == (~(uint32)0)) /* Link to another struct. */
       {
          uint32 tmp;
 
@@ -140,7 +140,7 @@ static SFORMAT *CheckS(SFORMAT *sf, uint32 tsize, char *desc)
 {
    while (sf->v)
    {
-      if (sf->s == ~0)
+      if (sf->s == (~(uint32)0))
       { /* Link to another SFORMAT structure. */
          SFORMAT *tmp;
          if ((tmp = CheckS((SFORMAT*)sf->v, tsize, desc)))
@@ -162,7 +162,7 @@ static SFORMAT *CheckS(SFORMAT *sf, uint32 tsize, char *desc)
 static int ReadStateChunk(memstream_t *mem, SFORMAT *sf, int size)
 {
    SFORMAT *tmp;
-   int temp;
+   uint64 temp;
    temp = memstream_pos(mem);
 
    while(memstream_pos(mem) < (temp + size))