/opt/IBM/openxlC/17.1.1/bin/ibm-clang -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations math/M_El.c -o math/M_El -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -latomic
math/M_El.c:8:26: error: use of undeclared identifier 'M_El'
long double  const foo = M_El;
                         ^
1 error generated.