/opt/IBM/openxlC/17.1.1/bin/ibm-clang -pthread  -Wall -Wextra -Werror=implicit-function-declaration stdlib/secure_getenv.c -o stdlib/secure_getenv -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -latomic
stdlib/secure_getenv.c:12:22: error: call to undeclared function 'secure_getenv'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]
        const char* value = secure_getenv("FOO");
                            ^
stdlib/secure_getenv.c:12:14: warning: incompatible integer to pointer conversion initializing 'const char *' with an expression of type 'int' [-Wint-conversion]
        const char* value = secure_getenv("FOO");
                    ^       ~~~~~~~~~~~~~~~~~~~~
1 warning and 1 error generated.