--- /dev/null
+https://gmplib.org/list-archives/gmp-bugs/2016-November/004032.html
+
+From f440c9134fb89cadf54daeb59c7a0feb7470562b Mon Sep 17 00:00:00 2001
+From: Mike Frysinger <vapier@gentoo.org>
+Date: Sat, 26 Nov 2016 16:35:46 -0500
+Subject: [PATCH] tune: fix spurious clock_gettime reference
+
+When running the tune program, the generated gmp-mparam.h header might
+include an invalid line leading to build failures like so:
+In file included from .../gmp-impl.h:145:0,
+ from mp_bases.c:4:
+../gmp-mparam.h:1:1: error: unknown type name 'clock_gettime'
+ clock_gettime is 1.000ns accurate
+
+This is because the tune source has one printf that is not protected
+by the verbose flag leading it to be written to the output.
+
+Credit to Conrad Kostecki for analysis.
+
+URL: https://bugs.gentoo.org/568320
+---
+ tune/time.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/tune/time.c b/tune/time.c
+index e0d262096396..d1efb0a6d35d 100644
+--- a/tune/time.c
++++ b/tune/time.c
+@@ -773,8 +773,9 @@ cgt_works_p (void)
+ }
+
+ cgt_unittime = unit.tv_sec + unit.tv_nsec * 1e-9;
+- printf ("clock_gettime is %s accurate\n",
+- unittime_string (cgt_unittime));
++ if (speed_option_verbose)
++ printf ("clock_gettime is %s accurate\n",
++ unittime_string (cgt_unittime));
+
+ if (cgt_unittime < 10e-9)
+ {
+--
+2.11.0.rc2
+