Re: [Boost-bugs] [Boost C++ Libraries] #8642: Global locale prevents from using Boost.Filesystem in global constructors and destructors

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #8642: Global locale prevents from using Boost.Filesystem in global constructors and destructors
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-10-31 22:16:50

#8642: Global locale prevents from using Boost.Filesystem in global constructors
and destructors
-------------------------------+------------------------
  Reporter:  andysem           |      Owner:  bemandawes
      Type:  Bugs              |     Status:  assigned
 Milestone:  To Be Determined  |  Component:  filesystem
   Version:  Boost 1.52.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+------------------------

Comment (by daniel kruegler):

 The following example should demonstrate the problem for every currently
 supported platform:

 {{{
 #include "boost/filesystem/path.hpp"

 namespace fs = boost::filesystem;

 template<class>
 struct conv_char;

 template<>
 struct conv_char<wchar_t>
 {
   typedef char value_type;
   static const value_type* file_name() { return
 "abcdefghijklmnopqrst.uvw"; }
 };

 template<>
 struct conv_char<char>
 {
   typedef wchar_t value_type;
   static const value_type* file_name() { return
 L"abcdefghijklmnopqrst.uvw"; }
 };

 typedef conv_char<fs::path::value_type> path_conv_char;

 struct A
 {
   A()
   {
   }

   ~A()
   {
     fs::path pa(path_conv_char::file_name());
   }

   static A& instance()
   {
     static A result;
     return result;
   }

 };

 struct B
 {
   B()
   {
   }

   ~B()
   {
     A::instance();
     fs::path pb(path_conv_char::file_name());
   }
 } b;

 int main()
 {
 }

 }}}

 The code ensures that we perform a code conversion in all cases and takes
 advantage of the life-cycle rules of objects with static storage duration.
 It gives me a seg fault using gcc and a similar crash for Visual Studio in
 the destructor of A. The example provokes that the locale produced by
 path_locale() (within path.cpp) is already destroyed when pa becomes
 constructed, because by path_locale() holds another function local static.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/8642#comment:4>
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