> On Jan 19, 2017, at 7:01 PM, Matt Wette <matt.we...@gmail.com> wrote:
>
>
>> On Jan 18, 2017, at 6:26 PM, Andy Wingo <wi...@pobox.com
>> <mailto:wi...@pobox.com>> wrote:
>>
>> We are pleased to announce GNU Guile release 2.1.6.
>>
>> Guile 2.1.6 is the sixth pre-release in what will eventually become the
>> 2.2 release series. We encourage you to test this release and provide
>> feedback to guile-devel@gnu.org <mailto:guile-devel@gnu.org>.
>
> Saw this one last round. Mac OS, now gcc-6.3.0:
>
> ;;; ("#i1@-0" 1.0 -0.0)
> FAIL: numbers.test: string->number: valid complex number strings
>
> I am going to see if I can generate the assembly.
Short story: scm_c_make_polar is broken for the Mac. Guile needs to decide if
it want to use __sincos() on Mac, or suppress optimization, or ...
I was able to get the above to work (guile-2.1.5) by using
SCM
+#ifdef __APPLE__
+__attribute__((optimize("O0")))
+#endif
scm_c_make_polar (double mag, double ang)
In scm_c_make_polar, “gcc -O2” turns sin(), cos() into cexp(), since cexp(i*x)
= cos(x) + i*sin(x):
gcc -O0 =>
LM4339:
movq -32(%rbp), %rax
movd %rax, %xmm0
call _sin
movd %xmm0, %rax
movq %rax, -8(%rbp)
LM4340:
movq -32(%rbp), %rax
movd %rax, %xmm0
call _cos
movd %xmm0, %rax
movq %rax, -16(%rbp)
gcc -O2 =>
pxor %xmm0, %xmm0
LVL2703:
call _cexp
I wrote a little C program to show that cexp() does not preserve the
zero-signed-ness:
cos,sin: +1.000000 -0.000000
__sincos: +1.000000 -0.000000
cexp: +1.000000 +0.000000
The scm_c_make_polar will use sincos() if available, but macOS does not have
sincos(), it has __sincos().
#include <stdio.h>
#include <stdint.h>
#include <math.h>
#include <complex.h>
extern double z, p, n;
int main() {
double complex c;
double d, sine, cosine;
d = z*n;
printf(" cos,sin: %+f %+f\n", cos(d), sin(d));
__sincos(d, &sine, &cosine);
printf("__sincos: %+f %+f\n", cosine, sine);
c = cexp(CMPLX(0.0, d));
printf(" cexp: %+f %+f\n", creal(c), cimag(c));
}
double z = 0.0, p = +1.0, n = -1.0;
Incidentally, the above program will not compile on my machine w/ gcc-6.3.0.
“gcc -std=c11” or “gcc -std=c99” will not recognize the standard macro CMPLX().
