Re: [Tinycc-devel] Error compiling musl (_Complex not supported): Waiting for a release

[Brian Mayer]

Hello again.

> Very long ago I did similar tries. As a workaround, I rewrote the
> syscall wrapper in musl[1].
>
> For the reason, I think there's something wrong in x86-64 asm constraint
> computation, since r10 is always in a register. satisfying the
> constraint.
>
> Cheers,
> Yao Zi
Thanks for the help, but It didn't work, I got the same error message.
But I wasn't able to apply your change in exactly the same way,
because I didn't find the file src/internal/x86_64/syscall.S, so I
changed the file arch/x86_64/syscall_arch.h to add your assembly. So
the function becomes:

static __inline long __syscall6(long n, long a1, long a2, long a3,
long a4, long a5, long a6)
{
        unsigned long ret;
        __asm__ __volatile__ (
                "movq %%rdi, %%rax\n"
                "movq %%rsi, %%rdi\n"
                "movq %%rdx, %%rsi\n"
                "movq %%rcx, %%rdx\n"
                "movq %%r8, %%r10\n"
                "movq %%r9, %%r8\n"
                "movq 8(%%rsp), %%r9\n"
                "syscall\n"
                : "=a"(ret)
                : "r"(n), "r"(a1), "r"(a2),
                  "r"(a3), "r"(a4), "r"(a5), "r"(a6)
                : "rcx", "r11", "memory"                  // clobbers: rcx, r11
        );                   // <- line 69
        return ret;
}

I got the same error but now in line 69. Is this function correct?

Thanks.