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Compiler Command-line Options
Usage
This option can help you port source code that has been written for architectures without
alignment requirements. You can achieve finer control of access to unaligned data, with
less impact on the quality of generated code, using the __packed qualifier.
Restrictions
De-aligning pointers might increase the code size, even on CPUs with unaligned access
support. This is because only a subset of the load and store instructions benefit from
unaligned access support. The compiler is unable to use multiple-word transfers or
coprocessor-memory transfers, including hardware floating-point loads and stores,
directly on unaligned memory objects.
Note
• Code size might increase significantly when compiling for CPUs without
hardware support for unaligned access, for example, pre-v6 architectures.
• This option does not affect the placement of objects in memory, nor the layout and
padding of structures.
See also
• __packed on page 4-11
• #pragma pack(n) on page 4-68
• Aligning data on page 5-25 in the Compiler User Guide.
2.1.132 --preinclude=filename
This option instructs the compiler to include the source code of the specified file at the
beginning of the compilation.
Syntax
--preinclude=filename
Where:
filename
is the name of the file whose source code is to be included.
Usage
This option can be used to establish standard macro definitions. The filename is
searched for in the directories on the include search list.
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