On AIX, jextract miscomputes alignment for double and pointer types due to differences in the AIX ABI when compared to other platforms.

Structs containing double fields fail with:
1. Unsupported layout: 4%D8
2. Invalid alignment constraint for member layout
Pointer constant extraction test fail:
Expected -1, found 4294967295
reason : Clang macro detection runs in 32-bit mode causing incorrect __UINTPTR_MAX__