Re: [boost] [thread] Can't use boost/thread/mutex.hpp without boost_system

Subject: Re: [boost] [thread] Can't use boost/thread/mutex.hpp without boost_system
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2012-01-21 17:29:34

Le 20/01/12 08:42, Anthony Williams a écrit :
> On 19/01/12 21:39, Vicente J. Botet Escriba wrote:
>> Le 19/01/12 13:12, Artyom Beilis a écrit :
>>> ----- Original Message -----
>>>> From: Anthony Williams<anthony.ajw_at_[hidden]>
>>>> On 18/01/12 14:01, Vicente Botet wrote:
>>>>> I was not aware that Boost.Thread was working as a header only 
>>>>> library.
>>>> This was a much-requested feature, so I made sure that boost::mutex
>>>> at least was
>>>> usable header-only.
>>>>
>> Oh, I remember that now.
>>> So would this be fixed or I should switch to lightweight mutex?
>>>
>>>
>> As far as Boost.System is not-header-only we can not have both:
>> boost::mutex header-only and compliant with c++11.
>> As said before, I could let the user the possibility to set Boost.Thread
>> to don't use Boost.System via BOOST_THREAD_DONT_USE_SYSTEM. Artyom,
>> Anthony is this satisfactory for you?
>
> That sounds reasonable to me: if people wish to use Boost.Thread 
> header-only then they can define the macro, but anyone who needs to 
> use the full features must link against the library, so can cope with 
> the additional dependency on Boost.System.
>
> It would be great if we could ensure that code with incompatible 
> settings wouldn't link. We could mask out the parts of Boost.Thread 
> that do need the library with that macro, for starters, so we don't 
> need separate builds of the library with and without that macro.
>
> Anthony
Hi,

Ihave found that a little patch to Boost.System could make it 
header-only. It seems that Beman has already tried it, but there are 
some errors. Here it is the patch

device3-1:trunk viboes$ svn diff boost/system libs/system
Index: boost/system/error_code.hpp
===================================================================
--- boost/system/error_code.hpp    (revision 76354)
+++ boost/system/error_code.hpp    (working copy)
@@ -504,7 +504,7 @@

  #include <boost/config/abi_suffix.hpp> // pops abi_prefix.hpp pragmas

-# ifdef BOOST_ERROR_CODE_HEADER_ONLY
+# ifdef BOOST_SYSTEM_INLINED
  #   include <boost/../libs/system/src/error_code.cpp>
  # endif

Index: libs/system/src/error_code.cpp
===================================================================
--- libs/system/src/error_code.cpp    (revision 76354)
+++ libs/system/src/error_code.cpp    (working copy)
@@ -407,20 +407,20 @@
    {

  # ifndef BOOST_SYSTEM_NO_DEPRECATED
-    BOOST_SYSTEM_DECL error_code throws; // "throw on error" special 
error_code;
+    BOOST_SYSTEM_DECL BOOST_SYSTEM_INLINE error_code throws; // "throw 
on error" special error_code;
                                           //  note that it doesn't 
matter if this
                                           //  isn't initialized before 
use since
                                           //  the only use is to take its
                                           //  address for comparison 
purposes
  # endif

-    BOOST_SYSTEM_DECL const error_category & system_category()
+    BOOST_SYSTEM_DECL BOOST_SYSTEM_INLINE const error_category & 
system_category()
      {
        static const system_error_category  system_category_const;
        return system_category_const;
      }

-    BOOST_SYSTEM_DECL const error_category & generic_category()
+    BOOST_SYSTEM_DECL BOOST_SYSTEM_INLINE const error_category & 
generic_category()
      {
        static const generic_error_category generic_category_const;
        return generic_category_const;

Arytom, please could you try the patch to see if this could work for you 
(define BOOST_SYSTEM_INLINED)? If it is the case, we could see with 
Beman if he can apply the patch on trunk.

Best,
Vicente