Fujitsu MB91150 Series, Hardware Manual, Page: 477 / 512

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APPENDIX D Notes on Using the Little-Endian Area
If structure member locations do not match, do not allocate structure variables in the little-
endian area.
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Manipulation of a non-character type array by using a character-string handling function
The character-string handling functions provided in the standard library perform processing in
units of bytes. They will therefore not produce correct results if processing is performed by using
a character-string handling function for an area with a type other than char, unsigned char, and
signed char allocated in the little-endian area.
Do not attempt to perform such processing.
[Erroneous example] Transfer of word data with memcpy
The execution result of the above example is shown below. It is wrong as result of a word-data
transfer.
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Specification of the -K lib option during use of a character-string handling function
When the -K lib option is specified, the compiler performs inline expansion for some character-
string handling functions. To optimize processing, the compiler may change the processing to
half word-level or word-level processing.
This type of processing does therefore not lead to the correct results for a little-endian area.
When processing is performed for the little-endian area by using character-string-handling
functions, do not specify the -K lib option.
Do not specify the -04 option, which contains the -K lib option, or the -K speed option.
int big = 0x01020304; /* Big-endian area */
extern int little; /* Little-endian area */
memcpy(&little,&big,4); /* Transfer with memcpy */}
01 02 03 04 01 02 03 04
04 03 02 01
(Big-endian area) (Little-endian area)
(Correct result)
memcpy