HP Fortran Programmer's Guide (B3908-90031; September 2011)

Migrating to HP Fortran
Incompatibilities with HP FORTRAN 77
Chapter 10222
Format field widths
HP 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.
Floating-point constants
The HP Fortran compiler differs from HP FORTRAN 77 in its handling of floating-point constants. The
HP Fortran compiler conforms to the standard: a single-precision constant is treated as a single-precision
data item in all situations, regardless of how many digits were supplied when specifying it.
HP FORTRAN 77 actually scans and saves constants internally in double precision. This behavior can
produce slightly different results.
In HP Fortran, the statement
+B +escape
-D +dlines
+es +extend_source
-F +cpp_keep
-L +list
-onetrip +onetrip
+Q +pre_include
+s
+langlvl
a
+T +fp_exception
+ttyunbuf +nottybuf
-U +uppercase
-u +implicit_none
-V
+list
a
a. Does not fully replace.
Table 10-2 f77 options replaced by f90 options (Continued)
f77 option f90 replacement