New comment by zlice on void-packages repository

https://github.com/void-linux/void-packages/pull/50600#issuecomment-2139330676

Comment:
Able to build aarch64 with some hackery.

classabbyamp said that aarch64 on void isn't built with vector math (`-march armv8-a`)

but for some reason this, and https://github.com/void-linux/void-packages/pull/50117 both seem to pick up `math.h` which includes `bits/math-vector.h` which has

```c
//#if __GNUC_PREREQ(9, 0) || __glibc_clang_prereq(11, 0)
//#  define __ADVSIMD_VEC_MATH_SUPPORTED
//typedef __float32x4_t __f32x4_t;
//typedef __float64x2_t __f64x2_t;
//#elif __glibc_clang_prereq(8, 0)
//#  define __ADVSIMD_VEC_MATH_SUPPORTED
//typedef __attribute__ ((__neon_vector_type__ (4))) float __f32x4_t;
//typedef __attribute__ ((__neon_vector_type__ (2))) double __f64x2_t;
//#endif
//
//#if __GNUC_PREREQ(10, 0) || __glibc_clang_prereq(11, 0)
//#  define __SVE_VEC_MATH_SUPPORTED
//typedef __svfloat32_t __sv_f32_t;
//typedef __svfloat64_t __sv_f64_t;
//typedef __svbool_t __sv_bool_t;
//#endif
```

Commenting this out, along with some patches to disable neon instructions (desmume's types.h and configure args to define RJPEG_NO_SIMD) will build (guessing at performance cost, but arm6/7 build without anything special)

Not sure why `math-vector.h` picks up vector math if it is disabled or how this affects other packages