sandbox/bugs/patience.c

Unreasonably long compilation times

This was fixed by this patch, but is still quite long on the server (approx. 25 seconds and only 2.5 seconds on my i7 laptop).

The compilation of the small program below takes very long, and this behaviour depends on some unexpected aspects.

1. The number of loop iterations (imax) changes the time, altough it saturates.
2. The repeated calls to my_fun() are also important
3. Setting the _FORTIFY_SOURCE=2 flag makes this issue (much) worse

See also here.

#include "utils.h"

void my_fun (Colormap map) {
  int imax = 1000; 
  double cmap [NCMAP][3];
  map (cmap);
  for (int i = 0; i < imax; i++)
    colormap_color (cmap, (float)i/(imax - 1), 0, 1);
}

int main() {
  int imax = 1000;
  for (int i = 0; i < imax; i++) {
    // Multiple calls
    my_fun (jet);
    my_fun (jet);
    my_fun (jet);
    my_fun (jet);
    my_fun (jet);
  }
}