Boost C++ Libraries: Ticket #12617: clock_gettime not available on OS X 10.11

Ion Gaztañaga — Sat, 26 Nov 2016 23:13:47 GMT

In theory clock_gettime is used if BOOST_INTERPROCESS_CLOCK_MONOTONIC is defined. This is defined if one of the following is defined:

CLOCK_MONOTONIC_PRECISE bsd

CLOCK_MONOTONIC_RAW linux

CLOCK_HIGHRES solaris

Is any of those defined in macos 10.11? In theory the implementation should use a mac-os specific code calling match kernel functions (BOOST_INTERPROCESS_MATCH_ABSOLUTE_TIME should be defined).

Could you please check why BOOST_INTERPROCESS_MATCH_ABSOLUTE_TIME is not defined in mac os 10.11?

Chris Newbold — Tue, 17 Jan 2017 13:04:45 GMT

It appears that the macOS 10.12 SDK, which is what is used with XCode 8, defines both CLOCK_MONOTONIC and CLOCK_MONOTONIC_RAW which then causes Boost.Interprocess to follow the Linux branch and reach for clock_gettime. That works fine when actually running on a 10.12 machine, but 10.11 does not have clock_gettime so you get a busted executable that dies at runtime with an unresolved external.

Unfortunately Apple does not condition the definition of these macros on the deployment target, so even telling XCode 8 that you're targeting 10.11 results in references to clock_gettime.

rjain — Tue, 31 Jan 2017 06:27:47 GMT

We applied the following patch. So even if CLOCK_MONOTINIC and CLOCK_MONOTONIC_RAW are defined we explicitly include "mach_time.h". Hence no reference to _clock_gettime()

//Xcode 8 fix due to ::clock_gettime issue
#  if (defined(macintosh) || defined(__APPLE__) || defined(__APPLE_CC__))
#     include <mach/mach_time.h>  // mach_absolute_time, mach_timebase_info_data_t
#     define BOOST_INTERPROCESS_MATCH_ABSOLUTE_TIME
#  elif defined(CLOCK_MONOTONIC_PRECISE)   //BSD
#     define BOOST_INTERPROCESS_CLOCK_MONOTONIC CLOCK_MONOTONIC_PRECISE
#  elif defined(CLOCK_MONOTONIC_RAW)     //Linux
#     define BOOST_INTERPROCESS_CLOCK_MONOTONIC CLOCK_MONOTONIC_RAW
#  elif defined(CLOCK_HIGHRES)           //Solaris
#     define BOOST_INTERPROCESS_CLOCK_MONOTONIC CLOCK_HIGHRES
#  elif defined(CLOCK_MONOTONIC)         //POSIX (AIX, BSD, Linux, Solaris)
#     define BOOST_INTERPROCESS_CLOCK_MONOTONIC CLOCK_MONOTONIC

status changed; resolution set

Ion Gaztañaga — Mon, 06 Feb 2017 13:14:11 GMT

status new → closed
resolution → fixed

Thanks for the patch. Applied in:

https://github.com/boostorg/interprocess/commit/e9251cd22a3371299dea33bb0a8a9ba0d73e0c06