From 7dba09af47dd3daa1562a6332a643a1a59dba4a8 Mon Sep 17 00:00:00 2001
From: Yann Collet <cyan@fb.com>
Date: Tue, 16 Jan 2018 10:21:37 -0800
Subject: [PATCH] use more restrictive conditions for clock_gettime()

---
 programs/util.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/programs/util.h b/programs/util.h
index fc7f63e..a3576d7 100644
--- a/programs/util.h
+++ b/programs/util.h
@@ -141,6 +141,7 @@ extern "C" {
 *  Time functions
 ******************************************/
 #if defined(_WIN32)   /* Windows */
+
     typedef LARGE_INTEGER UTIL_time_t;
     UTIL_STATIC UTIL_time_t UTIL_getTime(void) { UTIL_time_t x; QueryPerformanceCounter(&x); return x; }
     UTIL_STATIC U64 UTIL_getSpanTimeMicro(UTIL_time_t clockStart, UTIL_time_t clockEnd)
@@ -165,7 +166,9 @@ extern "C" {
         }
         return 1000000000ULL*(clockEnd.QuadPart - clockStart.QuadPart)/ticksPerSecond.QuadPart;
     }
+
 #elif defined(__APPLE__) && defined(__MACH__)
+
     #include <mach/mach_time.h>
     typedef U64 UTIL_time_t;
     UTIL_STATIC UTIL_time_t UTIL_getTime(void) { return mach_absolute_time(); }
@@ -189,7 +192,9 @@ extern "C" {
         }
         return ((clockEnd - clockStart) * (U64)rate.numer) / ((U64)rate.denom);
     }
-#elif (PLATFORM_POSIX_VERSION >= 200112L)
+
+#elif (PLATFORM_POSIX_VERSION >= 200112L) && (defined __UCLIBC__ || ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 17) || __GLIBC__ > 2))
+
     #include <time.h>
     typedef struct timespec UTIL_time_t;
     UTIL_STATIC UTIL_time_t UTIL_getTime(void)
@@ -227,7 +232,9 @@ extern "C" {
         nano += diff.tv_nsec;
         return nano;
     }
+
 #else   /* relies on standard C (note : clock_t measurements can be wrong when using multi-threading) */
+
     typedef clock_t UTIL_time_t;
     UTIL_STATIC UTIL_time_t UTIL_getTime(void) { return clock(); }
     UTIL_STATIC U64 UTIL_getSpanTimeMicro(UTIL_time_t clockStart, UTIL_time_t clockEnd) { return 1000000ULL * (clockEnd - clockStart) / CLOCKS_PER_SEC; }
-- 
2.7.4