POSIX [1] makes it clear that when the value to be returned would cause underflow, it should set errno to ERANGE.
[1] <https://pubs.opengroup.org/onlinepubs/9699919799/functions/strtod.html> This test case fails with error code 4 on Cygwin 2.9. ========================== foo.c ========================== #include <stdlib.h> #include <errno.h> #include <float.h> #include <math.h> int main () { const char input[] = "1E-100000"; char *ptr; long double result; errno = 0; result = strtold (input, &ptr); if (!(ptr == input + 9)) return 1; if (!(0.0L <= result && result <= LDBL_MIN)) return 2; if (signbit (result)) return 3; if (result == 0.0L && errno != ERANGE) return 4; return 0; } ============================================================ $ gcc -Wall foo.c $ ./a.exe $ echo $? 4 The corresponding test case for strtod() / 'double' succeeds. Bruno -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
