2.8 Influencing runtime behavior
These options affect the runtime behavior of programs compiled with GNU Fortran.
- Specify the representation of data for unformatted files. Valid
values for conversion are: `native', the default; `swap',
swap between big- and little-endian; `big-endian', use big-endian
representation for unformatted files; `little-endian', use little-endian
representation for unformatted files.
This option has an effect only when used in the main program.
CONVERT specifier and the GFORTRAN_CONVERT_UNIT environment
variable override the default specified by -fconvert.
- Disable range checking of input values during integer
For example, GNU Fortran will give an error if an input value is
outside of the relevant range of [
HUGE()]. In other words,
INTEGER (kind=4) :: i , attempting to read -2147483648 will
give an error unless -fno-range-check is given.
- Specify the length of record markers for unformatted files.
Valid values for length are 4 and 8. Default is 4.
This is different from previous versions of gfortran,
which specified a default record marker length of 8 on most
systems. If you want to read or write files compatible
with earlier versions of gfortran, use -frecord-marker=8.
- Specify the maximum length for a subrecord. The maximum permitted
value for length is 2147483639, which is also the default. Only
really useful for use by the gfortran testsuite.
- When enabled, floating point numbers of value zero with the sign bit set
are written as negative number in formatted output and treated as
negative in the
fno-sign-zero does not
print the negative sign of zero values and regards zero as positive
number in the
SIGN intrinsic for compatibility with F77.
Default behavior is to show the negative sign.