[boost] [testing] How do you interpret the SHA1 revision (outdated results)?

Subject: [boost] [testing] How do you interpret the SHA1 revision (outdated results)?
From: John Maddock (john_at_[hidden])
Date: 2014-01-23 05:14:18

So... I'm looking into Boost.Regex and I'm seeing some failures which appear 
to refer to outdated sources (line numbers are all wrong for current 
source), for example: 
http://www.boost.org/development/tests/develop/developer/output/marshall-mac-boost-bin-v2-libs-regex-test-regex_regress_noeh-test-clang-darwin-4-2-1-debug-exception-handling-off-link-static-threading-multi-regress.html

But how on earth do I check this?  Reported run date is yesterday, but this 
was fixed/changed on Dec 20th: almost a month ago.  And the revision listed 
on the page is a SHA1 which I can't seem to relate to anything useful?

Thanks, John.