C++编译器(特别是g++)能否重新排列结构体的内部元素?
我遇到了一些奇怪的行为,我的一个结构体包含以下内容:
Struct SomeStruct{
...
...
long someLong;
long someLongArray[25];
unsigned long someUnsignedLong;
unsigned long someUnsignedLongArray[8];
unsigned long int someUnsignedLongInt;
...
...
};
当我将这些输出到文件时,someUnsignedLongArray和someLongArray的顺序似乎被颠倒了(即在someUnsignedLong之后出现了someLongArray[]中的元素,在someLong之后出现了someUnsignedLongArray[]中的元素)。这种情况可能吗?
谢谢。
更新: 按要求,我正在使用以下方式写出结构:
int fd = open(fspec,O_RDWR|O_CREAT|O_TRUNC,0666);
int writeRes = write(fd,(char *)&someStruct,sizeof(SomeStruct));
为了完整起见,以下是完整的结构体:
struct SomeStruct{
byte someByte;
byte someByteArray[6];
char someChar;
char someCharArray[5];
char someCharArrayArray[3][5];
short someShort;
signed short someShortArray[2];
unsigned short someUnsignedShort;
unsigned short someUnsignedShortArray[8];
int someInt;
int someIntArray[3];
int someIntArrayArrayArrayArray[4][3][2][6];
int *pSomeInt;
unsigned int someUnsignedInt;
unsigned int someUnsignedIntArray[9];
long someLong;
long someLongArray[25];
unsigned long someUnsignedLong;
unsigned long someUnsignedLongArray[8];
unsigned long int someUnsignedLongInt;
long long someLongLong;
long long someLongLongArray[5];
bool someBool;
bool someBoolArray[3];
unsigned long long someUnsignedLongLong;
unsigned long long someUnsignedLongLongArray[5];
unsigned long long someUnsignedLongLongArrayArray[5][2];
unsigned long long int *pSomeUnsignedLongLongInt;
};