diff --git a/glib/gcharset.c b/glib/gcharset.c
index 9f91a9b48..48cb0ffae 100644
--- a/glib/gcharset.c
+++ b/glib/gcharset.c
@@ -377,7 +377,7 @@ g_get_console_charset (const char **charset)
           modifier = strchr (dot, '@');
           if (modifier == NULL)
             raw = dot;
-          else if (modifier - dot < sizeof (buf))
+          else if ((gsize) (modifier - dot) < sizeof (buf))
             {
               memcpy (buf, dot, modifier - dot);
               buf[modifier - dot] = '\0';
diff --git a/glib/gdatetime.c b/glib/gdatetime.c
index a31afe713..429cadefc 100644
--- a/glib/gdatetime.c
+++ b/glib/gdatetime.c
@@ -893,8 +893,9 @@ static GDateTime *
 g_date_time_new_from_timeval (GTimeZone      *tz,
                               const GTimeVal *tv)
 {
-  if ((gint64) tv->tv_sec > G_MAXINT64 - 1 ||
-      !UNIX_TO_INSTANT_IS_VALID ((gint64) tv->tv_sec + 1))
+  gint64 tv_sec = tv->tv_sec;
+
+  if (tv_sec > G_MAXINT64 - 1 || !UNIX_TO_INSTANT_IS_VALID (tv_sec + 1))
     return NULL;
 
   return g_date_time_from_instant (tz, tv->tv_usec +
diff --git a/glib/genviron.c b/glib/genviron.c
index 04e9ab0a0..44e10d4bd 100644
--- a/glib/genviron.c
+++ b/glib/genviron.c
@@ -454,7 +454,7 @@ g_getenv (const gchar *variable)
   GQuark quark;
   gchar *value;
   wchar_t dummy[2], *wname, *wvalue;
-  int len;
+  DWORD len;
 
   g_return_val_if_fail (variable != NULL, NULL);
   g_return_val_if_fail (g_utf8_validate (variable, -1, NULL), NULL);
diff --git a/glib/ghostutils.c b/glib/ghostutils.c
index dff4a1997..24a7d37bb 100644
--- a/glib/ghostutils.c
+++ b/glib/ghostutils.c
@@ -128,15 +128,18 @@ punycode_encode (const gchar *input_utf8,
 {
   guint delta, handled_chars, num_basic_chars, bias, j, q, k, t, digit;
   gunichar n, m, *input;
-  glong input_length;
+  glong written_chars;
+  gsize input_length;
   gboolean success = FALSE;
 
   /* Convert from UTF-8 to Unicode code points */
   input = g_utf8_to_ucs4 (input_utf8, input_utf8_length, NULL,
-			  &input_length, NULL);
+			  &written_chars, NULL);
   if (!input)
     return FALSE;
 
+  input_length = (gsize) (written_chars > 0 ? written_chars : 0);
+
   /* Copy basic chars */
   for (j = num_basic_chars = 0; j < input_length; j++)
     {
diff --git a/glib/gslice.c b/glib/gslice.c
index 690d21e07..190b20634 100644
--- a/glib/gslice.c
+++ b/glib/gslice.c
@@ -380,7 +380,7 @@ slice_config_init (SliceConfig *config)
   {
 
   wchar_t wvalue[128];  /* at least big enough for `always-malloc,debug-blocks` */
-  int len;
+  gsize len;
 
   len = GetEnvironmentVariableW (L"G_SLICE", wvalue, G_N_ELEMENTS (wvalue));