diff --git a/glib/gstrfuncs.h b/glib/gstrfuncs.h
index 569f96977..8a6830294 100644
--- a/glib/gstrfuncs.h
+++ b/glib/gstrfuncs.h
@@ -147,7 +147,8 @@ gboolean             (g_str_has_prefix) (const gchar *str,
                                          const gchar *prefix);
 
 #if G_GNUC_CHECK_VERSION (2, 0)
-#if !defined (__GTK_DOC_IGNORE__) && !defined (__GI_SCANNER__)
+#ifndef __GTK_DOC_IGNORE__
+#ifndef __GI_SCANNER__
 
 /* This macro is defeat a false -Wnonnull warning in GCC.
  * Without it, it thinks strlen and memcmp may be getting passed NULL
@@ -220,7 +221,8 @@ gboolean             (g_str_has_prefix) (const gchar *str,
     (g_strdup) ((STR))                                                        \
   )
 
-#endif /* !defined (__GTK_DOC_IGNORE__) && !defined (__GI_SCANNER__) */
+#endif /* !defined (__GI_SCANNER__) */
+#endif /* !defined (__GTK_DOC_IGNORE__) */
 #endif /* G_GNUC_CHECK_VERSION (2, 0) */
 
 /* String to/from double conversion functions */
diff --git a/glib/gtimezone.c b/glib/gtimezone.c
index 20f99a621..4a4a2d010 100644
--- a/glib/gtimezone.c
+++ b/glib/gtimezone.c
@@ -445,9 +445,7 @@ zone_for_constant_offset (GTimeZone *gtz, const gchar *name)
   gtz->transitions = NULL;
 }
 
-#ifdef G_OS_UNIX
-
-#if defined(__sun) && defined(__SVR4)
+#if defined(G_OS_UNIX) && defined(__sun) && defined(__SVR4)
 /*
  * only used by Illumos distros or Solaris < 11: parse the /etc/default/init
  * text file looking for TZ= followed by the timezone, possibly quoted
@@ -513,6 +511,7 @@ zone_identifier_illumos (void)
 }
 #endif /* defined(__sun) && defined(__SRVR) */
 
+#ifdef G_OS_UNIX
 /*
  * returns the path to the top of the Olson zoneinfo timezone hierarchy.
  */