Hi,

indeed, the issue seems to be in libc. I can reproduce the problem with 
a simple C program:

#include <stdio.h>
#include <stdlib.h>
#include <locale.h>

int main(int argc, char** argv)
{
    setlocale (LC_ALL, "");

    struct lconv* loc = localeconv();
    printf("Thousands Separator: <%s>\n", loc->thousands_sep);

    for(int i = 1; i <argc; i++) {
       int    n = atoi(argv[i]);
       double f = atof(argv[i]);
       printf("double <%'10.0f>\tint <%'10d>\n", f, n);
    }
    return 0;
}

Output with LC_NUMERIC=nb_NO.UTF-8:

Thousands Separator: < >
double <         1>     int <         1>
double <        10>     int <        10>
double <       100>     int <       100>
double <     1 000>     int <   1 000>
double <    10 000>     int <  10 000>
double <   100 000>     int < 100 000>
double < 1 000 000>     int <1 000 000>
double <10 000 000>     int <10 000 000>

So, for a float (%f), the output is as expected, while it is wrong for 
an integer (%d).

-- 
Best regards / Mit freundlichen Grüßen / Med vennlig hilsen

=======================================================================
  Thomas Dreibholz

  Simula Metropolitan Centre for Digital Engineering
  Centre for Resilient Networks and Applications
  Pilestredet 52
  0167 Oslo, Norway
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  E-Mail:dreibh@simula.no
  Homepage:http://simula.no/people/dreibh
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