We have an issue of gpgscm on s390x.
The _flag field should be compatible to vector element for gc.
On the machine with 64-bit big endian, LSB of _flag is not the LSB of the word of vector element when we don't have this fix.
This is not yet perfect patch, it's just for testing.
This doesn't work for LLP64 system (we need long long there), only for LP64 or LP32.
For real use, we need to detect endian-ness and size of int and add padding.