Failing to build static lib with GCC 4.8 and C++11

[DenizThatMenace]

Compiling the newest Boost release (version 1.64.0) fails when trying to compile Boost.Fiber as static library with GCC 4.8 and -std=c++11.

This seems to be related to this issue with Boost.Context. The call to callcc is an ambiguous overload.

common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber
common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build
common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8
common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release
common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static
common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi
common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo
gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/algorithm.o
gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/round_robin.o
gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/shared_work.o
gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/work_stealing.o
gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/barrier.o
gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/condition_variable.o
gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o
libs/fiber/src/context.cpp: In constructor ‘boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)’:
libs/fiber/src/context.cpp:236:14: error: call of overloaded ‘callcc(const std::allocator_arg_t&, const boost::context::preallocated&, const default_stack&, boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5)’ is ambiguous
             });
              ^
libs/fiber/src/context.cpp:236:14: note: candidates are:
In file included from ./boost/fiber/context.hpp:28:0,
                 from libs/fiber/src/context.cpp:7:
./boost/context/continuation.hpp:469:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, StackAlloc, Fn&&, Arg ...) [with StackAlloc = boost::context::preallocated; Fn = const boost::context::basic_fixedsize_stack<boost::context::stack_traits>&; Arg = {boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5}]
 callcc( std::allocator_arg_t, StackAlloc salloc, Fn && fn, Arg ... arg) {
 ^
./boost/context/continuation.hpp:483:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, boost::context::preallocated, StackAlloc, Fn&&, Arg ...) [with StackAlloc = boost::context::basic_fixedsize_stack<boost::context::stack_traits>; Fn = boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5; Arg = {}]
 callcc( std::allocator_arg_t, preallocated palloc, StackAlloc salloc, Fn && fn, Arg ... arg) {
 ^
./boost/context/continuation.hpp:514:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, boost::context::preallocated, StackAlloc, Fn&&) [with StackAlloc = boost::context::basic_fixedsize_stack<boost::context::stack_traits>; Fn = boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5]
 callcc( std::allocator_arg_t, preallocated palloc, StackAlloc salloc, Fn && fn) {
 ^
./boost/context/continuation.hpp:457:1: note: boost::context::continuation boost::context::callcc(Fn&&, Arg ...) [with Fn = const std::allocator_arg_t&; Arg = {boost::context::preallocated, boost::context::basic_fixedsize_stack<boost::context::stack_traits>, boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5}; <template-parameter-1-3> = void]
 callcc( Fn && fn, Arg ... arg) {
 ^

    "g++-4.8"  -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pthread -m64 -m64 -fpic  -std=c++11   -m64 -fpic    -DBOOST_ALL_NO_LIB=1 -DBOOST_DISABLE_ASSERTS -DBOOST_FIBERS_SOURCE -DNDEBUG  -I"." -c -o "/home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o" "libs/fiber/src/context.cpp"

...failed gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o...

HTH,
Deniz Bahadir

PS: I reported this issue already for the beta releases of Boost 1.64.0 on the Boost mailing-list but it obviously got not much attention.

[olk]

problem of gcc-4.8/9 Am 20.04.2017 11:18 vorm. schrieb "Deniz Bahadir" <notifications@github.com

…

: Compiling the newest Boost release (version *1.64.0*) fails when trying to compile *Boost.Fiber* as *static library* with *GCC 4.8* and -std=c++11 . This seems to be related to this issue <boostorg/context#52> with *Boost.Context*. The call to callcc is an ambiguous overload. common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8 common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/algorithm.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/round_robin.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/shared_work.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/work_stealing.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/barrier.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/condition_variable.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o libs/fiber/src/context.cpp: In constructor ‘boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)’: libs/fiber/src/context.cpp:236:14: error: call of overloaded ‘callcc(const std::allocator_arg_t&, const boost::context::preallocated&, const default_stack&, boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5)’ is ambiguous }); ^ libs/fiber/src/context.cpp:236:14: note: candidates are: In file included from ./boost/fiber/context.hpp:28:0, from libs/fiber/src/context.cpp:7: ./boost/context/continuation.hpp:469:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, StackAlloc, Fn&&, Arg ...) [with StackAlloc = boost::context::preallocated; Fn = const boost::context::basic_fixedsize_stack<boost::context::stack_traits>&; Arg = {boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5}] callcc( std::allocator_arg_t, StackAlloc salloc, Fn && fn, Arg ... arg) { ^ ./boost/context/continuation.hpp:483:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, boost::context::preallocated, StackAlloc, Fn&&, Arg ...) [with StackAlloc = boost::context::basic_fixedsize_stack<boost::context::stack_traits>; Fn = boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5; Arg = {}] callcc( std::allocator_arg_t, preallocated palloc, StackAlloc salloc, Fn && fn, Arg ... arg) { ^ ./boost/context/continuation.hpp:514:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, boost::context::preallocated, StackAlloc, Fn&&) [with StackAlloc = boost::context::basic_fixedsize_stack<boost::context::stack_traits>; Fn = boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5] callcc( std::allocator_arg_t, preallocated palloc, StackAlloc salloc, Fn && fn) { ^ ./boost/context/continuation.hpp:457:1: note: boost::context::continuation boost::context::callcc(Fn&&, Arg ...) [with Fn = const std::allocator_arg_t&; Arg = {boost::context::preallocated, boost::context::basic_fixedsize_stack<boost::context::stack_traits>, boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5}; <template-parameter-1-3> = void] callcc( Fn && fn, Arg ... arg) { ^ "g++-4.8" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pthread -m64 -m64 -fpic -std=c++11 -m64 -fpic -DBOOST_ALL_NO_LIB=1 -DBOOST_DISABLE_ASSERTS -DBOOST_FIBERS_SOURCE -DNDEBUG -I"." -c -o "/home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o" "libs/fiber/src/context.cpp" ...failed gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o... HTH, Deniz Bahadir PS: I reported this issue already for the beta releases of *Boost 1.64.0* on the Boost mailing-list but it obviously got not much attention. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#121>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA30QD3_Eh8oIQ0sGX9aww3144mrtVhGks5rxyLWgaJpZM4NCwgC> .

[olk]

I mean it's a bug of gcc-4.8/4.9 - the code compiles with gcc-5/6, clang , intel and msvc Am 20.04.2017 11:37 vorm. schrieb "Oliver Kowalke" <oliver.kowalke@gmail.com

:

problem of gcc-4.8/9 Am 20.04.2017 11:18 vorm. schrieb "Deniz Bahadir" <notifications@github.com

…

: Compiling the newest Boost release (version *1.64.0*) fails when trying to compile *Boost.Fiber* as *static library* with *GCC 4.8* and -std=c++11 . This seems to be related to this issue <boostorg/context#52> with *Boost.Context*. The call to callcc is an ambiguous overload. common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8 common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi common.mkdir /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/algorithm.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/round_robin.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/shared_work.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/algo/work_stealing.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/barrier.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/condition_variable.o gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o libs/fiber/src/context.cpp: In constructor ‘boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)’: libs/fiber/src/context.cpp:236:14: error: call of overloaded ‘callcc(const std::allocator_arg_t&, const boost::context::preallocated&, const default_stack&, boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5)’ is ambiguous }); ^ libs/fiber/src/context.cpp:236:14: note: candidates are: In file included from ./boost/fiber/context.hpp:28:0, from libs/fiber/src/context.cpp:7: ./boost/context/continuation.hpp:469:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, StackAlloc, Fn&&, Arg ...) [with StackAlloc = boost::context::preallocated; Fn = const boost::context::basic_fixedsize_stack<boost::context::stack_traits>&; Arg = {boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5}] callcc( std::allocator_arg_t, StackAlloc salloc, Fn && fn, Arg ... arg) { ^ ./boost/context/continuation.hpp:483:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, boost::context::preallocated, StackAlloc, Fn&&, Arg ...) [with StackAlloc = boost::context::basic_fixedsize_stack<boost::context::stack_traits>; Fn = boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5; Arg = {}] callcc( std::allocator_arg_t, preallocated palloc, StackAlloc salloc, Fn && fn, Arg ... arg) { ^ ./boost/context/continuation.hpp:514:1: note: boost::context::continuation boost::context::callcc(std::allocator_arg_t, boost::context::preallocated, StackAlloc, Fn&&) [with StackAlloc = boost::context::basic_fixedsize_stack<boost::context::stack_traits>; Fn = boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5] callcc( std::allocator_arg_t, preallocated palloc, StackAlloc salloc, Fn && fn) { ^ ./boost/context/continuation.hpp:457:1: note: boost::context::continuation boost::context::callcc(Fn&&, Arg ...) [with Fn = const std::allocator_arg_t&; Arg = {boost::context::preallocated, boost::context::basic_fixedsize_stack<boost::context::stack_traits>, boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::__lambda5}; <template-parameter-1-3> = void] callcc( Fn && fn, Arg ... arg) { ^ "g++-4.8" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pthread -m64 -m64 -fpic -std=c++11 -m64 -fpic -DBOOST_ALL_NO_LIB=1 -DBOOST_DISABLE_ASSERTS -DBOOST_FIBERS_SOURCE -DNDEBUG -I"." -c -o "/home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o" "libs/fiber/src/context.cpp" ...failed gcc.compile.c++ /home/jenkins/workspace/TEST_Boost_Build/gcc48/build/boost/boost/bin.v2/libs/fiber/build/gcc-4.8/release/link-static/threading-multi/context.o... HTH, Deniz Bahadir PS: I reported this issue already for the beta releases of *Boost 1.64.0* on the Boost mailing-list but it obviously got not much attention. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#121>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA30QD3_Eh8oIQ0sGX9aww3144mrtVhGks5rxyLWgaJpZM4NCwgC> .

[DenizThatMenace]

Mmhhh... I see.

You could provide a workaround by adding copies of the original callcc function-templates to Boost.Context with different names (e.g. callcc_no_args callcc_with_args callcc_no_args_palloc callcc_with_args_palloc) which are only available if GCC 4.8/4.9 are used. You then have to make sure to call these specific functions from Boost.Fiber if either GCC 4.8 or 4.9 is used.

Of course this is kind of ugly but might help in this case.

I tried it out and it works. See the attached patches (against the Boost 1.64.0 release).

context__include__continuation.hpp.diff.txt
fiber__src__context.cpp.diff.txt

[DaoWen]

I was able to build Boost.Fiber with toolset=gcc-4.9 and run all tests successfully using the patches in PR #122 and PR boostorg/context#55. Using toolset=gcc-4.8, a few tests failed, but most passed.

Would you be able to verify?

[DenizThatMenace]

I can confirm that Boost.Fiber from Boost releases 1.64.0 with these patches compiles fine with GCC 4.8.

I assume that during compilation with b2 all tests were compiled and run automatically. And none of the tests failed! 👍

(However, I just tried to compile Boost.Fiber and no other Boost-library which depends on it or Boost.Context.)

[DaoWen]

I assume that during compilation with b2 all tests were compiled and run automatically.

I actually don't think the tests are run unless you explicitly run them. I'm fairly new to the Boost build toolchain, so there might be better ways to do this, but here's how I run the tests for a specific module:

./b2 toolset=gcc-4.9 cxxflags="-std=c++11" --build-dir="/tmp/nick/boost/1.64" libs/fiber/test

If it says anything about "skipped" or "failed" targets at the end of the run, then that indicates a problem.

[DenizThatMenace]

OK, you are right. I somehow thought that the unit-tests would have been run automatically. (Maybe that is the case for some other Boost-libraries?)

One unit-test failed and a second was skipped because of this, when compiling with GCC 4.8. GCC 6 compiles fine instead (while Clang 3.8 does only compile the library but does not even try to compile the libraries).

So I can confirm your findings.

The failure seems to be due to the unit-test somehow trying to use the deleted copy-constructor of a move-only type (std::atomic). Maybe just the unit-test is not entirely correct (for the standard-library of GCC 4.8) and needs to be fixed (or a workaround)?

[DaoWen]

The failure seems to be due to the unit-test somehow trying to use the deleted copy-constructor of a move-only type (std::atomic).

Yes, that's the same error I observed.

Maybe just the unit-test is not entirely correct (for the standard-library of GCC 4.8) and needs to be fixed (or a workaround)?

I'm guessing that this is actually an issue/deficiency in the C++ standard library that ships with GCC 4.8, which means the boost library can't really work around it (aside from maybe documenting the limitation and suggesting to upgrade your compiler toolchain). But, the good news is that everything else worked, so as long as you don't try to copy something with a deleted copy constructor into a Boost.Fiber promise, then I think you should be fine using GCC 4.8.

[olk]

should be fixed now (not the atomic ctor issue), ty

[quangbuule]

I think this problem is not solved entirely (maybe related to gcc 4.9), here is my build error (branch develop):

libs/fiber/src/context.cpp: In constructor ‘boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)’:
libs/fiber/src/context.cpp:236:14: error: call of overloaded ‘callcc(const std::allocator_arg_t&, const boost::context::preallocated&, const default_stack&, boost::fibers::context::context(boost::fibers::dispatcher_context_t, const boost::context::preallocated&, const default_stack&, boost::fibers::scheduler*)::<lambda(boost::context::continuation&&)>)’ is ambiguous
             });
              ^
libs/fiber/src/context.cpp:236:14: note: candidates are:
In file included from ./boost/fiber/context.hpp:28:0,
                 from libs/fiber/src/context.cpp:7:

---

Updated: I fixed by checking out the boost_context to develop branch too.