HP Fortran Programmer's Guide (March 2010)

Compiling and linking
Compiling with the f90 command
Chapter 248
Disables the passing of libraries to the linker. This is useful when symbols
are resolved at runtime through dynamically loaded libraries.
+nopadsharedcommon
Do not pad shared common blocks to a multiple of 8 bytes. This option is
useful when sharing shared common blocks between f77-generated
programs and f90-generated programs. All source files referencing the same
shared common block must be compiled with the same setting of this flag.
-O[n]
-O invokes the optimizer, where n is the level of optimization, 0 - 4. The
default is optimization level 2.
This option is provided for compatibility and is functionally the same as the
+On option. The only difference between the two is that the level number is
optional for the -O option. For more information about the levels of
optimization, see the +On option.
+On
+O invokes the optimizer, where n is the level of optimization, 0 - 4. The -g
option is compatible with the +O0, +O1, and +O2 options.
Table 2-6 lists and describes the different levels of optimization.
NOTE See the Parallel Programming Guide for HP-UX Systems for a
detailed description of optimization levels and methods.
+O[no]optimization
+O[no] options enable or disable specific optimizations or classes of
optimizations (for example, optimizations that affect compilation time). For
detailed information about +O[no]optimization, see “Using optimization
options” on page 62.
Table 2-6 Levels of optimization
Level Optimizations
0 Local optimizations, including constant folding and partial
evaluation of test conditions.