diff --git a/src/glx/x11/indirect_size.c b/src/glx/x11/indirect_size.c
index 2063f38c995..2a1a54408e1 100644
--- a/src/glx/x11/indirect_size.c
+++ b/src/glx/x11/indirect_size.c
@@ -29,6 +29,10 @@
 #include <GL/gl.h>
 #include "indirect_size.h"
 
+#  if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
+#    define HAVE_ALIAS
+#  endif
+
 #  if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
 #    define PURE __attribute__((pure))
 #  else