[Boost-bugs] [Boost C++ Libraries] #7434: Lock used in flyweight causes erroneous "unused variable" warning when compiling with clang

Subject: [Boost-bugs] [Boost C++ Libraries] #7434: Lock used in flyweight causes erroneous "unused variable" warning when compiling with clang
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-09-27 08:31:07

#7434: Lock used in flyweight causes erroneous "unused variable" warning when
compiling with clang
-------------------------------------------------+--------------------------
 Reporter:  Pierre Imai <pierre.imai@…>          |       Owner:  joaquin  
     Type:  Bugs                                 |      Status:  new      
Milestone:  To Be Determined                     |   Component:  flyweight
  Version:  Boost 1.51.0                         |    Severity:  Problem  
 Keywords:  clang unused variable warning        |  
-------------------------------------------------+--------------------------
 The lock functionality in boost/flyweight/detail/flyweight_core.hpp causes
 the following warning when compiled with "Apple clang version 4.0
 (tags/Apple/clang-421.0.60) (based on LLVM 3.1svn)" with option "-Wunused-
 variable":

 {{{
 In file included from /opt/local/include/boost/flyweight/flyweight.hpp:22:
 /opt/local/include/boost/flyweight/detail/flyweight_core.hpp:189:22:
 error: unused variable 'lock' [-Werror,-Wunused-variable]
     lock_type        lock(mutex());
 }}}

 This problem can be fixed by adding the following code to the file, before
 / after the corresponding blocks for MSVC

 {{{
 #ifdef __clang__
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wunused-variable"
 #endif
 }}}

 {{{
 #ifdef __clang__
 #pragma clang diagnostic pop
 #endif
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7434>
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