cc -O2 -pipe  -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations langinfo/ERA.c -o langinfo/ERA -D_POSIX_C_SOURCE=202405L  -lm -lpthread 
langinfo/ERA.c:2:17: error: use of undeclared identifier 'ERA'
int const foo = ERA;
                ^
1 error generated.