Table 38 f77 options replaced by f90 options (continued)
f77 option | f90 replacement |
+dlines | |
|
|
+es | +extend_source |
|
|
+cpp_keep | |
|
|
+list | |
|
|
+onetrip | |
|
|
+Q | +pre_include |
|
|
+s | a+langlvla |
|
|
+T | +fp_exception |
|
|
+ttyunbuf | +nottybuf |
|
|
+uppercase | |
|
|
+implicit_none | |
|
|
+lista |
a Does not fully replace.
Format field widthsHP Fortran 90 supports format field widths up to 32767. In contrast, HP FORTRAN 77 allows format field widths up to 2147483639, which is close to 2**31.
The HP Fortran compiler differs from HP FORTRAN 77 in its handling of
In HP Fortran, the statement
DOUBLE PRECISION x = 3.1415926535
will initialize to only 32 bits worth of the constant because it interprets the constant as single precision. Under HP Fortran, a constant must have a D exponent or aKIND suffix to be interpreted as double precision.
In programs that use double precision exclusively, you should consider using the
+real_constant=doubleoption, which causes real constants to default to double precision. For more information, see “Controlling data storage” (page 67).
Intrinsic functionsThe Fortran 90 standard has introduced new intrinsics that may collide with function or subroutine names in FORTRAN 77 code. You can resolve such collisions by declaring all procedures that you have
Also, HP FORTRAN 77 allows intrinsics to accept a wider variety of argument types than HP Fortran does. For example, in HP FORTRAN 77 the MAX andMIN intrinsics can take arguments of different types, while HP Fortran follows the standard and requires all arguments to be of the same type.
132 Migrating to HP Fortran