[OpenIndiana-discuss] Problem building xcreensaver 6.15

[russell]

Good Morning Peter

Thank you changing xscreensaver-6.15/hacks/glx/platonicfolding.c from

static inline void get_sun_direction(double jd, float sun[4])
{
   double n, utc;
   double l, g, gr, lambda, lambdar, epsilon, epsilonr;
   double alpha, delta, eot, lat, lon;
   float latr, lonr;

   n = jd-2451545.0;
   utc = 24.0*modulo(jd-0.5,1.0);
   l = modulo(280.460+0.9856474*n,360.0);
   g = modulo(357.528+0.9856003*n,360.0);
   gr = rad(g);
   lambda = modulo(l+1.915*sin(gr)+0.020*sin(2.0*gr),360.0);
   epsilon = 23.439-0.0000004*n;
   lambdar = rad(lambda);
   epsilonr = rad(epsilon);
   alpha = 
modulo(deg(atan2(cos(epsilonr)*sin(lambdar),cos(lambdar))),360.0);
   delta = deg(asin(sin(epsilonr)*sin(lambdar)));
   eot = modulo(l-alpha+180.0,360.0)-180.0;
   lat = delta;
   lon = -15.0*(utc-12.0+eot*(4.0/60.0));
   latr = (float)rad(lat);
   lonr = (float)rad(lon);
   sun[0] = cosf(latr)*cosf(lonr);
   sun[1] = cosf(latr)*sinf(lonr);
   sun[2] = sinf(latr);
   sun[3] = 0.0f;
}

to

static inline void get_sun_direction(double jd, float thesun[4])
{
   double n, utc;
   double l, g, gr, lambda, lambdar, epsilon, epsilonr;
   double alpha, delta, eot, lat, lon;
   float latr, lonr;

   n = jd-2451545.0;
   utc = 24.0*modulo(jd-0.5,1.0);
   l = modulo(280.460+0.9856474*n,360.0);
   g = modulo(357.528+0.9856003*n,360.0);
   gr = rad(g);
   lambda = modulo(l+1.915*sin(gr)+0.020*sin(2.0*gr),360.0);
   epsilon = 23.439-0.0000004*n;
   lambdar = rad(lambda);
   epsilonr = rad(epsilon);
   alpha = 
modulo(deg(atan2(cos(epsilonr)*sin(lambdar),cos(lambdar))),360.0);
   delta = deg(asin(sin(epsilonr)*sin(lambdar)));
   eot = modulo(l-alpha+180.0,360.0)-180.0;
   lat = delta;
   lon = -15.0*(utc-12.0+eot*(4.0/60.0));
   latr = (float)rad(lat);
   lonr = (float)rad(lon);
   thesun[0] = cosf(latr)*cosf(lonr);
   thesun[1] = cosf(latr)*sinf(lonr);
   thesun[2] = sinf(latr);
   thesun[3] = 0.0f;
}

Allowed the GL screensavers to be built, however they crashed on 
execution changing the xscreensaver ./configure options to use 
--with-glx fixed the GL screensavers, apparently this was something also 
experienced by a BSD build which was corrected with the --with-glx so I 
decided to give it a try.

./configure --prefix=/opt/xscreensaver --with-glx

Kind Regards

Russell

On 2026-07-11 10:46, Peter Tribble wrote:
> On Sat, Jul 11, 2026 at 10:37 AM russell via openindiana-discuss
> <openindiana-discuss at openindiana.org> wrote:
>> Hi
>>
>> Attempting to build xscreensaver using using gcc 10.4
>>
>> $ CFLAGS="-Wimplicit-function-declaration -Wnested-externs" ./configure
>> --prefix=/opt/xscreensaver
>>
>> Everything is fine until
>>
> ...
>> platonicfolding.c:937:55: error: expected ';', ',' or ')' before numeric
>> constant
>>     937 | static inline void get_sun_direction(double jd, float sun[4])
>>         |  ^~~
> The word "sun" is a predefined constant on Solaris and illumos, so
> using it as a variable
> name ends in disaster. Simply replace the "sun" there with any other
> word (say, "xsun")
> and the same replacement where the variable is used in the function,
> and all will be well.
>