cc -pthread -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations math/M_SQRT3l.c -o math/M_SQRT3l -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -lcrypt -latomic math/M_SQRT3l.c:8:26: error: 'M_SQRT3l' undeclared here (not in a function); did you mean 'M_SQRT2'? 8 | long double const foo = M_SQRT3l; | ^~~~~~~~ | M_SQRT2