XL Fortran Enterprise Edition for AIX : User's Guide - IBM

-C Option
Syntax
-C
CHECK | NOCHECK
Checks each reference to an array element, array section, or character substring for
correctness.
Rules
At compile time, if the compiler can determine that a reference goes out of bounds,
the severity of the error reported is increased to S (severe) when this option is
specified.
At run time, if a reference goes out of bounds, the program generates a SIGTRAP
signal. By default, this signal ends the program and produces a core dump. This is
expected behaviour and does not indicate there is a defect in the compiler product.
Because the run-time checking can slow execution, you should decide which is the
more important factor for each program: the performance impact or the possibility
of incorrect results if an error goes undetected. You might decide to use this option
only while testing and debugging a program (if performance is more important) or
also for compiling the production version (if safety is more important).
Related Information
The -C option prevents some of the optimizations that the “-qhot Option” on page
171 performs. You may want to remove the -C option after debugging of your code
is complete and to add the -qhot option to achieve a more thorough optimization.
The valid bounds for character substring expressions differ depending on the
setting of the -qzerosize option. See “-qzerosize Option” on page 268.
“-qsigtrap Option” on page 232 and “Installing an Exception Handler” on page 298
describe how to detect and recover from SIGTRAP signals without ending the
program.
-qcheck is the long form of -C.
XL Fortran Compiler-Option Reference 103