The package seems to fail on all 64-bit architectures that are not x86_64 because the define __LP64__ is used to decide whether the SSE2 specific header emmintrin.h is available.
However, __LP64__ is defined on all 64 pit archs and not only on x86_64. On Debian replacing all instances of __LP64__ with __SSE2__ would probably do the trick, although I'm not sure whether __LP64__ is only used to decide about the us of SSE2, i.e. the code may still fail on other 64 bit archs, but then for other reasons. For upstream the solution should be somewhat different, because they also support the MS visual studio compiler that doesn't define __LP64__ nor __SSE2__.