Error suggesting that OSX 10.12 APIs aren't available in nixpkgs master

build.log

warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels' does not exist, ignoring
these derivations will be built:
  /nix/store/3qkd06j28dvfvdsxj9kzmlnqa989h2kg-kakoune-unwrapped-2019.07.01.drv
building '/nix/store/3qkd06j28dvfvdsxj9kzmlnqa989h2kg-kakoune-unwrapped-2019.07.01.drv'...
unpacking sources
unpacking source archive /nix/store/1ia0x1br942ibipr0rwj0gqzssrlccyd-source
source root is source
patching sources
configuring
no configure script, doing nothing
building
build flags: SHELL=/nix/store/mlsjkws5zc9dja87npqy8g1vrfx1rf23-bash-4.4-p23/bin/bash debug=no
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .alias_registry.opt.d -c -o .alias_registry.opt.o alias_registry.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .assert.opt.d -c -o .assert.opt.o assert.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .backtrace.opt.d -c -o .backtrace.opt.o backtrace.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .buffer.opt.d -c -o .buffer.opt.o buffer.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .buffer_manager.opt.d -c -o .buffer_manager.opt.o buffer_manager.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .buffer_utils.opt.d -c -o .buffer_utils.opt.o buffer_utils.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .changes.opt.d -c -o .changes.opt.o changes.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .client.opt.d -c -o .client.opt.o client.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .client_manager.opt.d -c -o .client_manager.opt.o client_manager.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .color.opt.d -c -o .color.opt.o color.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .command_manager.opt.d -c -o .command_manager.opt.o command_manager.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .commands.opt.d -c -o .commands.opt.o commands.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .completion.opt.d -c -o .completion.opt.o completion.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .context.opt.d -c -o .context.opt.o context.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .display_buffer.opt.d -c -o .display_buffer.opt.o display_buffer.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .env_vars.opt.d -c -o .env_vars.opt.o env_vars.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .event_manager.opt.d -c -o .event_manager.opt.o event_manager.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .exception.opt.d -c -o .exception.opt.o exception.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .face_registry.opt.d -c -o .face_registry.opt.o face_registry.cc
clang++ -I/opt/local/include -O3 -pedantic -std=c++17 -g -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare -Wno-address -MD -MP -MF .file.opt.d -c -o .file.opt.o file.cc
file.cc:277:42: error: 'uncaught_exceptions' is unavailable: introduced in macOS 10.12
      : m_fd{fd}, m_exception_count{std::uncaught_exceptions()} {}
                                         ^
/nix/store/5yismw8d67dxddvlcj7i3avkq8gzyb6h-libc++-7.1.0/include/c++/v1/exception:130:63: note: 'uncaught_exceptions' has been explicitly marked unavailable here
_LIBCPP_FUNC_VIS _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS int uncaught_exceptions() _NOEXCEPT;
                                                              ^
file.cc:281:54: error: 'uncaught_exceptions' is unavailable: introduced in macOS 10.12
        if (m_pos != 0 and m_exception_count == std::uncaught_exceptions())
                                                     ^
/nix/store/5yismw8d67dxddvlcj7i3avkq8gzyb6h-libc++-7.1.0/include/c++/v1/exception:130:63: note: 'uncaught_exceptions' has been explicitly marked unavailable here
_LIBCPP_FUNC_VIS _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS int uncaught_exceptions() _NOEXCEPT;
                                                              ^
2 errors generated.
make: *** [Makefile:104: .file.opt.o] Error 1
builder for '/nix/store/3qkd06j28dvfvdsxj9kzmlnqa989h2kg-kakoune-unwrapped-2019.07.01.drv' failed with exit code 2
error: build of '/nix/store/3qkd06j28dvfvdsxj9kzmlnqa989h2kg-kakoune-unwrapped-2019.07.01.drv' failed