cc -pthread   -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations math/M_PHI.c -o math/M_PHI -D_POSIX_C_SOURCE=202405L -lm -lpthread  -lgdbm_compat -lintl -lnetwork -lbsd -latomic
math/M_PHI.c:8:21: error: 'M_PHI' undeclared here (not in a function); did you mean 'M_PI'?
    8 | double  const foo = M_PHI;
      |                     ^~~~~
      |                     M_PI