tor.real fails to start on macOS 10.9

While trying to test Snowflake on a macOS 10.9 system (for #26251 (moved)), I encountered a different issue: tor.real fails to start. The error is:

dyld: lazy symbol binding failed: Symbol not found: _mach_approximate_time
  Referenced from: /Users/.../Desktop/Tor/TB nightly 2018-07-18/Tor Browser.app/Contents/MacOS/Tor/tor.real
  Expected in: /usr/lib/libSystem.B.dylib

At this point I don't know if this is a core tor bug or if it is caused by something in the Tor Browser 8.x build process.

changed milestone to %Tor: 0.3.5.x-final

added 033-backport 034-backport 035-must component::core tor/tor fast-fix ff60-esr milestone::Tor: 0.3.5.x-final owner::teor priority::medium regression resolution::fixed reviewer::nickm severity::normal status::closed tbb-needs type::defect version::tor 0.3.3.1-alpha labels

I found #24427 (moved) as well as https://developer.apple.com/documentation/kernel/1462443-mach_approximate_time (which does indicate that mach_approximate_time() is available in macOS 10.9 and newer).

Replying to mcs:

I found #24427 (moved) as well as https://developer.apple.com/documentation/kernel/1462443-mach_approximate_time (which does indicate that mach_approximate_time() is available in macOS 10.9 and newer).

Ah, but the macOS 10.9 header doesn't actually have that symbol: https://opensource.apple.com/source/xnu/xnu-2422.1.72/osfmk/mach/mach_time.h.auto.html

In fact, the symbol is only available in the macOS 10.10 header: https://opensource.apple.com/source/xnu/xnu-2782.1.97/osfmk/mach/mach_time.h.auto.html

(The kernel version index is here: https://opensource.apple.com/ )

So I will do something similar to #20235 (moved) here.

Trac:
Component: Applications/Tor Browser to Core Tor/Tor
Status: new to assigned
Milestone: N/A to Tor: 0.3.5.x-final
Version: N/A to Tor: 0.3.3.1-alpha
Keywords: N/A deleted, 034-backport, regression, tbb-needs, 033-backport, fast-fix added
Owner: tbb-team to teor

Oh, and the availability macro was only introduced in the 10.12 header, so there are two different bugs here: https://opensource.apple.com/source/xnu/xnu-3789.1.32/osfmk/mach/mach_time.h.auto.html

Unfortunately, I can't do the same checks for iOS, because the kernel headers aren't open-source. (I only have access to the latest headers, which claim that the symbol was introduced in iOS 8.0.) I've asked in #tor-mobile if they also need this fix.

See my branch bug26876_033.

On my macOS 10.13 with the default settings, it detects a Yosemite or later target, and the mach_approximate_time symbol is imported by the binary.

With -DMAC_OS_X_VERSION_MIN_REQUIRED=1009, it detects a pre-Yosemite target, and the mach_approximate_time symbol is not imported by the binary.

Trac:
Status: assigned to needs_review
Keywords: N/A deleted, 035-must added

Do we actually support OSX 10.9? Apple hasn't supported it since 2016.

(That is, according to https://trac.torproject.org/projects/tor/wiki/org/teams/NetworkTeam/SupportedPlatforms , we wouldn't ordinarily support 10.9, since it's "OSX past EOL". But if TB needs it, we should support it, and we should maybe revise our policy, I guess.)

https://www.mozilla.org/en-US/firefox/60.0esr/system-requirements/ has the system requirements for Firefox which we follow. Thus, if you could support 10.9 for the time being that would be neat.

My understanding is that Apple is fuzzy about what they support and what they do not support, but I think it is correct to infer based on the stream of security patches issued by Apple that 10.11 is the oldest version of macOS that they still support. But as gk said, Firefox still supports 10.9 and 10.10, so we would like Tor Browser to work on those systems as well.

Replying to nickm:

(That is, according to https://trac.torproject.org/projects/tor/wiki/org/teams/NetworkTeam/SupportedPlatforms , we wouldn't ordinarily support 10.9, since it's "OSX past EOL". But if TB needs it, we should support it, and we should maybe revise our policy, I guess.)

Replying to gk:

https://www.mozilla.org/en-US/firefox/60.0esr/system-requirements/ has the system requirements for Firefox which we follow. Thus, if you could support 10.9 for the time being that would be neat.

I updated our support policy so that we will Maintain:

• OS X / macOS supported by Tor Browser (but not Apple) https://trac.torproject.org/projects/tor/wiki/org/teams/NetworkTeam/SupportedPlatforms?action=diff&version=13

Let's handle support for unsupported Windows and Linux as needed.

Trac:
Reviewer: N/A to nickm

Very sorry, but I can't find the branch bug26876_033. Is it one of the ones that got lost when you recreated your github repository?

Trac:
Status: needs_review to needs_revision

Yes, thanks for your patience. It's there now.

Trac:
Status: needs_revision to needs_review

lgtm; merged to 0.3.3 and forward.

Trac:
Status: needs_review to closed
Resolution: N/A to fixed

closed

mentioned in issue #27482 (moved)

mentioned in issue #27693 (moved)

mentioned in issue #30126 (moved)

moved to tpo/core/tor#26876 (closed)