make -C .. CC=cc EXE=Schoenemann-5677772A make[1]: Entering directory '/tmp/tmpc17e2c_o/Schoenemann/Schoenemann-tmp' cd Schoenemann && clang++ -Wall -O3 -std=c++20 schoenemann.cpp search.cpp timeman.cpp helper.cpp tt.cpp main.cpp moveorder.cpp see.cpp tune.cpp tuneconsts.cpp datagen.cpp -o ../src/Schoenemann-5677772A In file included from schoenemann.cpp:9: In file included from ./schoenemann.h:4: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. In file included from search.cpp:1: In file included from ./search.h:3: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. In file included from timeman.cpp:1: In file included from ./timeman.h:3: In file included from ./consts.h:7: In file included from ./search.h:3: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. In file included from helper.cpp:1: In file included from ./helper.h:3: In file included from ./consts.h:7: In file included from ./search.h:3: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. In file included from main.cpp:1: In file included from ./schoenemann.h:4: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. In file included from moveorder.cpp:1: In file included from ./moveorder.h:5: In file included from ./consts.h:7: In file included from ./search.h:3: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. In file included from see.cpp:1: In file included from ./see.h:4: In file included from ./consts.h:7: In file included from ./search.h:3: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. In file included from datagen.cpp:1: In file included from ./datagen.h:2: In file included from ./consts.h:7: In file included from ./search.h:3: /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: error: call to consteval function 'std::chrono::hh_mm_ss::_S_fractional_width' is not a constant expression static constexpr unsigned fractional_width = {_S_fractional_width()}; ^ /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2320:48: note: undefined function '_S_fractional_width' cannot be used in a constant expression /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/chrono:2275:2: note: declared here _S_fractional_width() ^ 1 error generated. make[1]: *** [Makefile:13: all] Error 1 make[1]: Leaving directory '/tmp/tmpc17e2c_o/Schoenemann/Schoenemann-tmp' make: *** [Makefile:2: all] Error 2