Update comments now that LLVM PR3861 has been fixed. However, since conditionally removing the workaround makes the ABI dependent on LLVM version, I reconsidered that. (The same revision of LDC compiling for the same target should probably produce code that follows the same ABI, right?)

module mini.real1;

extern(C)
{
real tanl(real x);
int printf(char*, ...);
}

void main()
{
    real ans = tanl(0.785398163398);
    printf("%llf\n", ans);
    assert(ans > 0.999 && ans < 1.001);
}