Build error: error: ISO C++ forbids compound-literals [-Werror=pedantic]

[barracuda156]

[ 16%] Building CXX object tests/CMakeFiles/tests.dir/test_bt.cpp.o
cd /opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/build/tests && /opt/local/bin/ccache /opt/local/bin/g++-mp-14  -I/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0 -isystem /opt/local/include -pipe -Os -DNDEBUG -I/opt/local/include -D_GLIBCXX_USE_CXX11_ABI=0 -std=c++20 -mmacosx-version-min=10.6 -Wall -Wextra -Wconversion -Wpedantic -Wcast-align -Wunused -Werror -MD -MT tests/CMakeFiles/tests.dir/test_bt.cpp.o -MF CMakeFiles/tests.dir/test_bt.cpp.o.d -o CMakeFiles/tests.dir/test_bt.cpp.o -c /opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp
. . .
In file included from /opt/local/include/catch2/benchmark/catch_benchmark.hpp:14,
                 from /opt/local/include/catch2/benchmark/catch_benchmark_all.hpp:24,
                 from /opt/local/include/catch2/catch_all.hpp:25,
                 from /opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/common.h:2,
                 from /opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp:5:
/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp: In function 'void CATCH2_INTERNAL_TEST_39()':
/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp:717:67: error: ISO C++ forbids compound-literals [-Werror=pedantic]
  717 |     CHECK(buf_view(oxenc::apple_to_chars10(buf, (unsigned char){42})) == "42");
      |                                                                   ^
In file included from /opt/local/include/catch2/catch_test_macros.hpp:11,
                 from /opt/local/include/catch2/catch_template_test_macros.hpp:20,
                 from /opt/local/include/catch2/catch_all.hpp:37:
/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp:717:67: error: ISO C++ forbids compound-literals [-Werror=pedantic]
  717 |     CHECK(buf_view(oxenc::apple_to_chars10(buf, (unsigned char){42})) == "42");
      |                                                                   ^
/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp:717:67: error: ISO C++ forbids compound-literals [-Werror=pedantic]
  717 |     CHECK(buf_view(oxenc::apple_to_chars10(buf, (unsigned char){42})) == "42");
      |                                                                   ^
/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp:721:67: error: ISO C++ forbids compound-literals [-Werror=pedantic]
  721 |     CHECK(buf_view(oxenc::apple_to_chars10(buf, (unsigned char){42})) == "42");
      |                                                                   ^
/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp:721:67: error: ISO C++ forbids compound-literals [-Werror=pedantic]
  721 |     CHECK(buf_view(oxenc::apple_to_chars10(buf, (unsigned char){42})) == "42");
      |                                                                   ^
/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_net_oxenc/oxenc/work/oxen-encoding-1.1.0/tests/test_bt.cpp:721:67: error: ISO C++ forbids compound-literals [-Werror=pedantic]
  721 |     CHECK(buf_view(oxenc::apple_to_chars10(buf, (unsigned char){42})) == "42");
      |                                                                   ^
cc1plus: all warnings being treated as errors