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https://issues.apache.org/jira/browse/LOGCXX-528?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Robert Middleton updated LOGCXX-528:
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Fix Version/s: 0.12.1
> log4cxx fails to build on Centos 7.6 / g++ 4.8.5 / Boost 1.53
> -------------------------------------------------------------
>
> Key: LOGCXX-528
> URL: https://issues.apache.org/jira/browse/LOGCXX-528
> Project: Log4cxx
> Issue Type: Bug
> Affects Versions: 0.12.0
> Reporter: Russel Miranda
> Assignee: Robert Middleton
> Priority: Major
> Fix For: 0.12.1
>
>
> With:
> * CMake 3.13.4,
> * g++ 4.8.5
> * Boost 1.53.0
> ** thread
> ** chrono
> ** system
> ** date_time
> ** atomic
> * apr-1.6.2
> * apr-devel-1.6.2
> * apr-util-1.6.0
> * apr-util-devel-1.6.0
> CMake fails to properly detect the Boost threads package, due to a link error
> in the test build. There is no indication of a problem at the CMake stage
> other than the lack of output for the shared_mutex implementation:
> {{log4cxx configuration summary:}}
> {{Build shared library ............ : ON}}
> {{Build tests ..................... : ON}}
> {{Build site ...................... : OFF}}
> {{Install prefix .................. : /usr/local}}
> {{C++ compiler .................... : /usr/bin/c++}}
> {{log4cxx char API ................ : utf-8}}
> {{log4cxx wchar API ............... : ON}}
> {{log4cxx unichar API ............. : OFF}}
> {{logchar type .................... : utf-8}}
> {{charset ......................... : locale}}
> {{Using libESMTP .................. : OFF}}
> {{ODBC library .................... : OFF}}
> {{syslog .......................... : ON}}
> {{Qt support ...................... : OFF}}
> {{shared_mutex implementation ..... :}}
> This can be fixed by adding "-lboost_system" to CMAKE_CXX_FLAGS.
> After correcting the CMake problem, a make may be performed, which results in
> the compiler complaining that mutex is not found in the std:: namespace in a
> number of places. This can be rectified by adding "#include <mutex>" to:
> * log4cxx/src/main/include/log4cxx/helpers/appenderattachableimpl.h
> * log4cxx/src/main/include/log4cxx/helpers/aprinitializer.h
> * log4cxx/src/main/include/log4cxx/helpers/loglog.h
> * log4cxx/src/main/include/log4cxx/helpers/serversocket.h
> * log4cxx/src/main/include/log4cxx/level.h
> * log4cxx/src/main/include/log4cxx/rolling/action.h
> This may not be a minimal set, but it was sufficient to satisfy the build.
> Once these problems have been addressed, the compiler complains that the C++
> 17 feature "std::weak_from_this()" is not available. It is used in two places
> in log4cxx/src/main/cpp/hierarchy.cpp: line 226 and line 426.
> It may be preferable to create a local routine that stands in for
> "std::weak_from_this()", but I found it sufficient to just #if / #else /
> #endif around the single line in each location that called weak_from_this()
> and replace it with a two-step version similar to this:
> {{std::weak_ptr<Hierarchy> weak_handle = shared_from_this();}}
> {{logger->setHierarchy(weak_handle);}}
> in place of the single-step:
> {{logger->setHierarchy(weak_from_this());}}
> I used the precompiler test:
> {{#if __cplusplus >= 201500L}}
> That was sufficient to differentiate my {{g++ 4.8.5}} from more modern
> compilers that support C++ 17, but there may be more precise ways of
> achieving this end - I just don't have the ability to test on anything other
> than {{g++ 4.8.5}}.
> After making this change the build should complete successfully, and all
> 60/60 tests should pass.
> NOTE: Because g++ 4.8.5 does not support std::shared_mutex and is therefore
> dependent on Boost thread, and Boost thread itself is dependent on Boost
> system, it was required to link executables using this version of log4cxx w/
> Boost system as well. I suspect there may be Boost compile-time flags that
> might make that unnecessary, but my knowledge of Boost is not sufficient to
> achieve that goal.
>
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