cc -O2 -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations math/M_LN2l.c -o math/M_LN2l -D_POSIX_C_SOURCE=202405L  -lm -lpthread -lrt  -lintl -lcrypt
math/M_LN2l.c:8:26: error: 'M_LN2l' undeclared here (not in a function); did you mean 'M_LN2'?
    8 | long double  const foo = M_LN2l;
      |                          ^~~~~~
      |                          M_LN2