I don't have access to a 64 bit platform.. "Endianness" is always relevant as there is fundamental difference between say how Intel and say Motorola machines work.
This goes to the hardware level about how data is actually stored in sequential memory locations and is enforced by the hardware. If I do a binary byte dump to disk, of say array of 32 bit values on a VAX or Intel platform, nothing is gonna change the fact that this same array will look different on the disk from a binary byte dump from a Motorola platform.
The OP indicates that he is getting a syntax/compile-time error. Endianness doesn't matter at that point, which is what DrHyde indicated. And the likely explanation for the error is provided by almut in 794510.