From 99e071cf2c3c3557c2e755911f69b7372c66fe09 Mon Sep 17 00:00:00 2001
From: Jim Huang <jserv@biilabs.io>
Date: Sat, 24 Aug 2019 21:24:56 +0800
Subject: [PATCH] Link with -lrt for older glibc

Quoted from Linux Programmer's Manual (2017-09-15):
    #include <time.h>
    int clock_gettime(clockid_t clk_id, struct timespec *tp);
    Link with -lrt (only for glibc versions before 2.17).

This patch adds additional checks for librt availability and append
target_link_libraries accordingly. librt is absent on macOS.

Fixed #139
---
 CMakeLists.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c9de861..d44b340 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -108,6 +108,10 @@ if(WIN32)
   list(APPEND mi_libraries psapi shell32 user32)
 else()
   list(APPEND mi_libraries pthread)
+  find_library(LIBRT rt)
+  if(LIBRT)
+    list(APPEND mi_libraries ${LIBRT})
+  endif()
 endif()
 
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