Portability and migration
The options in this category
can help you maintain application behavior compatibility on past,
current, and future hardware, operating systems and compilers, or
help move your applications to an XL compiler with minimal change.
| Option name | Description |
|---|---|
| -fpack-struct (-qalign) | Specifies the alignment of data objects in storage, which avoids performance problems with misaligned data. |
| -qxlcompatmacros | Defines the following
legacy macros: |
__IBMCPP__, __xlC__, __xlC_ver__
, 
__IBMC__,
and __xlc__
. This option helps you
migrate programs from 
