cannot build Falcon new_engine

gistfile1.txt

on Fedora 20 x86_64, after setting all FALCON_BUILD_* to OFF in ccmake

% git log -1 HEAD | cat
commit 5c5ca3d39db30c22a4218bea40a45d2f94465f2d
Author: Giancarlo Niccolai <gc@niccolai.cc>
Date:   Wed Dec 3 00:05:30 2014 +0100

    Fixed compilation on FreeBSD 10.1 64Bit - Clang
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% ninja-build -k 1000
[10/494] Building CXX object engine/CM...Files/falcon_engine.dir/mt_posix.cpp.o
FAILED: /usr/bin/c++   -DFALCON_ENGINE_EXPORTS -Dfalcon_engine_EXPORTS -O3 -DNDEBUG -fPIC -I../include -Iinclude/falcon1.0.0 -Iengine/../include -I../engine/re2    -Wall -Wextra -Werror -Wno-error=uninitialized -lpthread -MMD -MT engine/CMakeFiles/falcon_engine.dir/mt_posix.cpp.o -MF "engine/CMakeFiles/falcon_engine.dir/mt_posix.cpp.o.d" -o engine/CMakeFiles/falcon_engine.dir/mt_posix.cpp.o -c ../engine/mt_posix.cpp
../engine/mt_posix.cpp:18:0: error: "_XOPEN_SOURCE_EXTENDED" redefined [-Werror]
 #define _XOPEN_SOURCE_EXTENDED
 ^
In file included from /usr/include/sys/types.h:25:0,
                 from /usr/include/sys/param.h:25,
                 from ../include/falcon/setup.h:191,
                 from ../engine/mt_posix.cpp:16:
/usr/include/features.h:169:0: note: this is the location of the previous definition
 # define _XOPEN_SOURCE_EXTENDED 1
 ^
cc1plus: all warnings being treated as errors
[239/494] Building CXX object engine/C...falcon_engine.dir/contextmanager.cpp.o
FAILED: /usr/bin/c++   -DFALCON_ENGINE_EXPORTS -Dfalcon_engine_EXPORTS -O3 -DNDEBUG -fPIC -I../include -Iinclude/falcon1.0.0 -Iengine/../include -I../engine/re2    -Wall -Wextra -Werror -Wno-error=uninitialized -lpthread -MMD -MT engine/CMakeFiles/falcon_engine.dir/contextmanager.cpp.o -MF "engine/CMakeFiles/falcon_engine.dir/contextmanager.cpp.o.d" -o engine/CMakeFiles/falcon_engine.dir/contextmanager.cpp.o -c ../engine/contextmanager.cpp
In file included from ../include/falcon/shared.h:21:0,
                 from ../include/falcon/contextmanager.h:23,
                 from ../engine/contextmanager.cpp:19:
../include/falcon/refcounter.h: In member function ‘virtual void* Falcon::ContextManager::run()’:
../include/falcon/refcounter.h:72:54: error: ‘msg.Falcon::CMMsg::m_data.Falcon::CMMsg::<anonymous union>::ctx’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
    void dec(__T* data) { if( atomicDec(m_count)<= 0) delete data; }
                                                      ^
../engine/contextmanager.cpp:270:13: note: ‘msg.Falcon::CMMsg::m_data.Falcon::CMMsg::<anonymous union>::ctx’ was declared here
       CMMsg msg;
             ^
../engine/contextmanager.cpp:302:7: error: ‘msg’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
       switch( msg.m_type )
       ^
cc1plus: all warnings being treated as errors
[359/494] Building CXX object engine/C.../falcon_engine.dir/re2/re2/regexp.cc.o
ninja: build stopped: cannot make progress due to previous errors.
[ninja-build -k 1000] 243.69s user, 12.56s kernel, 131M memory
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