libbacktrace: Conditionalize test timing on clock_gettime availability

	libbacktrace/
	PR other/67165
	* configure.ac: Check for clock_gettime.
	* config.h.in: Regenerate.
	* configure: Likewise.
	* ztest.c (average_time, test_large): Conditionalize test timing
	on clock_gettime availability.

From-SVN: r253344

libbacktrace/ChangeLog

+2017-10-02  Thomas Schwinge  <thomas@codesourcery.com>
+
+	PR other/67165
+	* configure.ac: Check for clock_gettime.
+	* config.h.in: Regenerate.
+	* configure: Likewise.
+	* ztest.c (average_time, test_large): Conditionalize test timing
+	on clock_gettime availability.
+
 2017-09-29  Tony Reix  <tony.reix@atos.net>
 
 	* xcoff.c: Initial support for DWARF debug sections in XCOFF.

libbacktrace/config.h.in

@@ -9,6 +9,9 @@
 /* Define to 1 if you have the __atomic functions */
 #undef HAVE_ATOMIC_FUNCTIONS
 
+/* Define to 1 if you have the `clock_gettime' function. */
+#undef HAVE_CLOCK_GETTIME
+
 /* Define to 1 if you have the declaration of `strnlen', and to 0 if you
    don't. */
 #undef HAVE_DECL_STRNLEN

libbacktrace/configure

@@ -12747,6 +12747,19 @@ $as_echo "#define HAVE_GETEXECNAME 1" >>confdefs.h
 
 fi
 
+# Check for the clock_gettime function.
+for ac_func in clock_gettime
+do :
+  ac_fn_c_check_func "$LINENO" "clock_gettime" "ac_cv_func_clock_gettime"
+if test "x$ac_cv_func_clock_gettime" = x""yes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_CLOCK_GETTIME 1
+_ACEOF
+
+fi
+done
+
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -pthread is supported" >&5
 $as_echo_n "checking whether -pthread is supported... " >&6; }
 if test "${libgo_cv_lib_pthread+set}" = set; then :

libbacktrace/configure.ac

@@ -388,6 +388,9 @@ if test "$have_getexecname" = "yes"; then
   AC_DEFINE(HAVE_GETEXECNAME, 1, [Define if getexecname is available.])
 fi
 
+# Check for the clock_gettime function.
+AC_CHECK_FUNCS(clock_gettime)
+
 dnl Test whether the compiler supports the -pthread option.
 AC_CACHE_CHECK([whether -pthread is supported],
 [libgo_cv_lib_pthread],

libbacktrace/ztest.c

@@ -43,6 +43,10 @@ POSSIBILITY OF SUCH DAMAGE.  */
 #include <zlib.h>
 #endif
 
+#ifdef HAVE_CLOCK_GETTIME
+# define TEST_TIMING
+#endif
+
 #include "backtrace.h"
 #include "backtrace-supported.h"
 
@@ -157,7 +161,7 @@ test_samples (struct backtrace_state *state)
     }
 }
 
-#ifdef HAVE_ZLIB
+#if defined HAVE_ZLIB && defined TEST_TIMING
 
 /* Given a set of TRIALS timings, discard the lowest and highest
    values and return the mean average of the rest.  */
@@ -216,6 +220,7 @@ test_large (struct backtrace_state *state)
   unsigned char *uncompressed_buf;
   size_t uncompressed_bufsize;
   int r;
+# ifdef TEST_TIMING
   clockid_t cid;
   struct timespec ts1;
   struct timespec ts2;
@@ -224,6 +229,7 @@ test_large (struct backtrace_state *state)
   const size_t trials = 16;
   size_t ctimes[16];
   size_t ztimes[16];
+# endif /* TEST_TIMING */
   static const char * const names[] = {
     "Mark.Twain-Tom.Sawyer.txt",
     "../libgo/go/compress/testdata/Mark.Twain-Tom.Sawyer.txt"
@@ -341,6 +347,8 @@ test_large (struct backtrace_state *state)
 
   printf ("PASS: inflate large\n");
 
+# ifdef TEST_TIMING
+
   for (i = 0; i < trials; ++i)
     {
       cid = CLOCK_REALTIME;
@@ -411,6 +419,8 @@ test_large (struct backtrace_state *state)
   printf ("zlib time:    : %zu ns\n", ztime);
   printf ("percentage    : %g\n", (double) ztime / (double) ctime);
 
+# endif /* TEST_TIMING */
+
   return;
 
  fail: