HP Compilers for HP Integrity Servers (September 2011)

Table 3 Options and pragmas for troubleshooting problems in optimized code
PurposeOption
Initializes all potentially-uninitialized variables with
zero.
+Oinitcheck
Initializes to zero any unspecified function
parameters at call sites, to avoid NaT values.
+Oparminit
Prevents all value-changing optimizations, even
contractions.
+Ofltacc=strict
In 32-bit mode, modifies the use of add pointer
instructions so that non-standard-conforming pointer
+Ocross_region_addressing
arithmetic works properly, incurring some
performance cost.
Turns off optimization for the named functions.+O0=name[,name]...
C/C++ pragma which forces the compiler to compile
subsequent code (up to the next opt_level
#pragma OPT_LEVEL n
pragma) at the given optimization level. Can only
specify an optimization level which is equal or lower
than the optimization level from the command-line.
Suppress aggressive assumptions made by the
compiler regarding the lack of integer arithmetic
overflow in the program.
+Ointeger_overflow=conservative
Additional Information
The HP Developer and Solution Partner Program (DSPP) web site contains useful
information, including a number of “webinars” on related topics, such as HP-UX compilers,
HP Caliper, and application performance tuning:
http://www.hp.com/go/dspp
Additional information about the ANSI C and C++ compilers is available at the following
locations:
http://www.hp.com/go/c
http://www.hp.com/go/aCC
Extensive documentation and technical usage notes on floating-point and math functions,
including the new decimal floating-point features, are available at:
http://www.hp.com/go/fp
Information about HP Code Advisor is available at:
http://www.hp.com/go/cadvise
Extensive documentation and technical usage notes on HP Caliper are available at:
Additional Information 33