boost::context for arm64?

I am trying to compile boost::context for iOS(armv7, armv7s, arm64):

errors

jump_arm_aapcs_macho_gas.S:52:18: error: ',' expected
    stmia a1, {v1-v8,sp-lr} @ save V1-V8,SP-LR
                 ^
jump_arm_aapcs_macho_gas.S:53:14: error: register expected
    str lr, [a1,#40] @ save LR as PC
             ^
jump_arm_aapcs_macho_gas.S:69:18: error: invalid variant 'use'
    mov a1, a3 @ use third arg as return value after jump
                 ^
jump_arm_aapcs_macho_gas.S:70:39: error: unexpected token at start of statement
                                    @ and as first arg in context function
                                      ^
jump_arm_aapcs_macho_gas.S:71:18: error: ',' expected
    ldmia a2, {v1-v8,sp-pc} @ restore v1-V8,SP-PC
                 ^

jump_arm_aapcs_macho_gas.S

.text
.globl _jump_fcontext
.align 2
_jump_fcontext:
    stmia   a1, {v1-v8,sp-lr}       @ save V1-V8,SP-LR
    str     lr, [a1,#40]            @ save LR as PC

#if (defined(__VFP_FP__) && !defined(__SOFTFP__))
    cmp     a4, #0                  @ test if fpu env should be preserved
    beq     1f

    mov     a4, a1
    add     a4, #52
    vstmia  a4, {d8-d15}            @ save S16-S31

    mov     a4, a2
    add     a4, #52
    vldmia  a4, {d8-d15}            @ restore S16-S31
1:
#endif

    mov     a1, a3                  @ use third arg as return value after jump
                                    @ and as first arg in context function
    ldmia   a2, {v1-v8,sp-pc}       @ restore v1-V8,SP-PC

If I remove arm64, and set the architecture to armv7 only, it compiles, so the code should be fine.

Is there any way to get this to compile for arm64?

ARM64 (AArch64) is pretty different from ARM32 (A32), both in instructions and the register set. The calling conventions (ABI) differs too. You'd need to rewrite the assembler snippets. I would recommend contacting the developer(s) since you don't seem to be familiar with the low-level details to do it yourself.