unable to build using clang

[RFoe]

 vcpkg install concurrencpp  --triplet x64-linux-clang-libcxx --clean-buildtrees-after-build --clean-packages-after-build 

cmake.config for x64-linux-clang-libcxx triplet:

set (VCPKG_TARGET_ARCHITECTURE x64)
set (VCPKG_CRT_LINKAGE dynamic)
set (VCPKG_LIBRARY_LINKAGE static)

set (VCPKG_CMAKE_SYSTEM_NAME Linux)

set (VCPKG_BUILD_TYPE release)

set (VCPKG_PLATFORM_TOOLSET clang)
set (
    VCPKG_CMAKE_CONFIGURE_OPTIONS
    -DCMAKE_C_COMPILER=/usr/bin/clang
    -DCMAKE_CXX_COMPILER=/usr/bin/clang++
    -DCMAKE_CXX_STANDARD=26
    # -DCMAKE_CXX_FLAGS="${CMAKE_CXX_FLAGS} -stdlib=libc++
    # -Wno-deprecated-declarations"
)

set (VCPKG_CXX_FLAGS "-stdlib=libc++ -std=c++26 -Wno-deprecated-declarations")
set (VCPKG_C_FLAGS "-stdlib=libc++")
set (VCPKG_CMAKE_C_FLAGS "${VCPKG_C_FLAGS}")
set (VCPKG_CMAKE_CXX_FLAGS "${VCPKG_CXX_FLAGS}")
set (VCPKG_LINKER_FLAGS "-stdlib=libc++ -lc++abi")

error traceback when building:

FAILED: CMakeFiles/concurrencpp.dir/source/runtime/runtime.cpp.o 
/usr/bin/clang++  -isystem /home/wang/git-repositories/vcpkg/buildtrees/concurrencpp/src/v.0.1.7-fbe774569e.clean/include -fPIC -stdlib=libc++ -std=c++26 -Wno-deprecated-declarations -O3 -DNDEBUG -std=c++26 -fvisibility=hidden -fvisibility-inlines-hidden -MD -MT CMakeFiles/concurrencpp.dir/source/runtime/runtime.cpp.o -MF CMakeFiles/concurrencpp.dir/source/runtime/runtime.cpp.o.d -o CMakeFiles/concurrencpp.dir/source/runtime/runtime.cpp.o -c /home/wang/git-repositories/vcpkg/buildtrees/concurrencpp/src/v.0.1.7-fbe774569e.clean/source/runtime/runtime.cpp
In file included from /home/wang/git-repositories/vcpkg/buildtrees/concurrencpp/src/v.0.1.7-fbe774569e.clean/source/runtime/runtime.cpp:1:
/home/wang/git-repositories/vcpkg/buildtrees/concurrencpp/src/v.0.1.7-fbe774569e.clean/include/concurrencpp/runtime/runtime.h:85:33: error: no member named 'is_abstract_v' in namespace 'std'
   85 |             static_assert(!std::is_abstract_v<executor_type>,
      |                                 ^~~~~~~~~~~~~
/home/wang/git-repositories/vcpkg/buildtrees/concurrencpp/src/v.0.1.7-fbe774569e.clean/include/concurrencpp/runtime/runtime.h:85:47: error: 'executor_type' does not refer to a value
   85 |             static_assert(!std::is_abstract_v<executor_type>,
      |                                               ^
/home/wang/git-repositories/vcpkg/buildtrees/concurrencpp/src/v.0.1.7-fbe774569e.clean/include/concurrencpp/runtime/runtime.h:76:24: note: declared here
   76 |         template<class executor_type, class... argument_types>
      |                        ^
/home/wang/git-repositories/vcpkg/buildtrees/concurrencpp/src/v.0.1.7-fbe774569e.clean/include/concurrencpp/runtime/runtime.h:85:61: error: expected expression
   85 |             static_assert(!std::is_abstract_v<executor_type>,

possibly <type_traits> not included (or indirectly included by libc++'s std headers) in <concurrencpp/runtime.h>