Our ARM assembly functions are aligned using the following construct:
__arm__ is only defined for 32-bit ARM targets, and this failed silently on Xcode 5.0.
In Xcode 5.1, ld now (thankfully) emits a warning on unaligned functions:
PC addresses must be 4 byte aligned (see also: ARMv8 Architecture Reference Manual). We need to fix our alignment #if guards to correctly align the ARM64 functions, which will queisce this linker warning.