Wicher

struct an char arrays alignment in 56800E

Discussion created by Wicher on Nov 14, 2007
Latest reply on Dec 14, 2007 by Pascal Irrle
I use 56f8366(56800E core). According to a manual for CodeWarrior for 56800E (Targeting_56800E, p. 125 and 126) structures are word aligned (or double word, if they contain any double word variables). Shouldn't that also mean that data inside the strucutres are word (dword) aligned? What I observed is (see comments):

struct booStruct{
int dummyInt;
char singleChar;
char charArray[10];
}

main()
{
struct booStruct structInstance;
char * charPtr;
char tempChar;
structInstance.singleChar = 0x12;
structInstance.charArray[0] = 0x34;
structInstance.charArray[1] = 0x56;
...
charPtr = &structInstance.charArray[0];
tempChar = *charPtr;
//ERROR after this line tempChar should be
//equal to 0x34, it is equal to 0x12. Moreover,
//according to debugger:
//- address of singleChar is 0x0300;
//- address of charArray[0] is 0x0300;
}
It's similiar with arrays of characters. Is that possible to align characters (not char arrays!) inside the struct to two-byte boundaries? Just to let pointers work correctly...

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