diff --git a/lib/common/mem.h b/lib/common/mem.h
index aff044de1..1c223fe5e 100644
--- a/lib/common/mem.h
+++ b/lib/common/mem.h
@@ -182,7 +182,7 @@ MEM_STATIC U32 MEM_swap32(U32 in)
 {
 #if defined(_MSC_VER)     /* Visual Studio */
     return _byteswap_ulong(in);
-#elif defined (__GNUC__)
+#elif defined (__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ >= 403)
     return __builtin_bswap32(in);
 #else
     return  ((in << 24) & 0xff000000 ) |
@@ -196,7 +196,7 @@ MEM_STATIC U64 MEM_swap64(U64 in)
 {
 #if defined(_MSC_VER)     /* Visual Studio */
     return _byteswap_uint64(in);
-#elif defined (__GNUC__)
+#elif defined (__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ >= 403)
     return __builtin_bswap64(in);
 #else
     return  ((in << 56) & 0xff00000000000000ULL) |
diff --git a/programs/fileio.c b/programs/fileio.c
index e905948bf..3cbd83ae0 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -91,8 +91,13 @@ static clock_t g_time = 0;
 
 #define MIN(a,b)    ((a) < (b) ? (a) : (b))
 
+/* ************************************************************
+* Avoid fseek()'s 2GiB barrier with MSVC, MacOS, *BSD, MinGW
+***************************************************************/
 #if defined(_MSC_VER) && _MSC_VER >= 1400
 #   define LONG_SEEK _fseeki64
+#elif !defined(__64BIT__) && (PLATFORM_POSIX_VERSION >= 200112L) /* No point defining Large file for 64 bit */
+#  define LONG_SEEK fseeko
 #elif defined(__MINGW32__) && !defined(__STRICT_ANSI__) && !defined(__NO_MINGW_LFS) && defined(__MSVCRT__)
 #   define LONG_SEEK fseeko64
 #elif defined(_WIN32) && !defined(__DJGPP__)
@@ -193,7 +198,7 @@ static FILE* FIO_openSrcFile(const char* srcFileName)
         f = stdin;
         SET_BINARY_MODE(stdin);
     } else {
-        if (!UTIL_doesFileExists(srcFileName)) {
+        if (!UTIL_isRegFile(srcFileName)) {
             DISPLAYLEVEL(1, "zstd: %s is not a regular file -- ignored \n", srcFileName);
             return NULL;
         }
diff --git a/programs/platform.h b/programs/platform.h
index 1b53e1f85..89a9f6cd4 100644
--- a/programs/platform.h
+++ b/programs/platform.h
@@ -51,8 +51,8 @@ extern "C" {
 /* *********************************************************
 *  Turn on Large Files support (>4GB) for 32-bit Linux/Unix
 ***********************************************************/
-#if !defined(__64BIT__)                               /* No point defining Large file for 64 bit */
-#  if !defined(_FILE_OFFSET_BITS)   
+#if !defined(__64BIT__) || defined(__MINGW32__)       /* No point defining Large file for 64 bit but MinGW-w64 requires it */
+#  if !defined(_FILE_OFFSET_BITS)
 #    define _FILE_OFFSET_BITS 64                      /* turn off_t into a 64-bit type for ftello, fseeko */
 #  endif
 #  if !defined(_LARGEFILE_SOURCE)                     /* obsolete macro, replaced with _FILE_OFFSET_BITS */
diff --git a/programs/util.h b/programs/util.h
index 95d39a509..364aa650f 100644
--- a/programs/util.h
+++ b/programs/util.h
@@ -182,17 +182,34 @@ UTIL_STATIC int UTIL_getFileStat(const char* infilename, stat_t *statbuf)
     return 1;
 }
 
+
 UTIL_STATIC int UTIL_isRegFile(const char* infilename)
 {
     stat_t statbuf;
     return UTIL_getFileStat(infilename, &statbuf); /* Only need to know whether it is a regular file */
 }
 
+
+UTIL_STATIC U32 UTIL_isDirectory(const char* infilename)
+{
+    int r;
+    stat_t statbuf;
+#if defined(_MSC_VER)
+    r = _stat64(infilename, &statbuf);
+    if (!r && (statbuf.st_mode & _S_IFDIR)) return 1;
+#else
+    r = stat(infilename, &statbuf);
+    if (!r && S_ISDIR(statbuf.st_mode)) return 1;
+#endif
+    return 0;
+}
+
+
 UTIL_STATIC U64 UTIL_getFileSize(const char* infilename)
 {
     int r;
 #if defined(_MSC_VER)
-    struct _stat64 statbuf;
+    struct __stat64 statbuf;
     r = _stat64(infilename, &statbuf);
     if (r || !(statbuf.st_mode & S_IFREG)) return 0;   /* No good... */
 #elif defined(__MINGW32__) && defined (__MSVCRT__)
@@ -218,37 +235,6 @@ UTIL_STATIC U64 UTIL_getTotalFileSize(const char** fileNamesTable, unsigned nbFi
 }
 
 
-UTIL_STATIC int UTIL_doesFileExists(const char* infilename)
-{
-    int r;
-#if defined(_MSC_VER)
-    struct __stat64 statbuf;
-    r = _stat64(infilename, &statbuf);
-    if (r || !(statbuf.st_mode & S_IFREG)) return 0;   /* No good... */
-#else
-    struct stat statbuf;
-    r = stat(infilename, &statbuf);
-    if (r || !S_ISREG(statbuf.st_mode)) return 0;   /* No good... */
-#endif
-    return 1;
-}
-
-
-UTIL_STATIC U32 UTIL_isDirectory(const char* infilename)
-{
-    int r;
-#if defined(_MSC_VER)
-    struct __stat64 statbuf;
-    r = _stat64(infilename, &statbuf);
-    if (!r && (statbuf.st_mode & _S_IFDIR)) return 1;
-#else
-    struct stat statbuf;
-    r = stat(infilename, &statbuf);
-    if (!r && S_ISDIR(statbuf.st_mode)) return 1;
-#endif
-    return 0;
-}
-
 /*
  * A modified version of realloc().
  * If UTIL_realloc() fails the original block is freed.
diff --git a/programs/windres/zstd32.res b/programs/windres/zstd32.res
index 748192a98..b5dd78db7 100644
Binary files a/programs/windres/zstd32.res and b/programs/windres/zstd32.res differ
diff --git a/programs/windres/zstd64.res b/programs/windres/zstd64.res
index ca4d8118f..32aff5542 100644
Binary files a/programs/windres/zstd64.res and b/programs/windres/zstd64.res differ