Bug#716775: libc6:amd64: mismatch between strcasecmp and toupper/tolower in tr_TR.iso88599 locale

[Vincent Lefevre <vincent@vinc17.net>]

Package: libc6
Version: 2.17-7
Severity: normal

There is a mismatch between strcasecmp and toupper/tolower in the
tr_TR.iso88599 locale:

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

int main (void)
{
  int i, j, k;
  char *infs[] = { "INF", "inf" };

  if (setlocale (LC_ALL, "") == NULL)
    {
      fprintf (stderr, "locale-test: can't set locales\n");
      exit (EXIT_FAILURE);
    }

  for (i = 0; i < 2; i++)
    for (j = 0; j < 4; j++)
      {
        char s[4];
        for (k = 0; k < 3; k++)
          {
            s[k] = infs[i][k];
            if (j > k)
              s[k] = (i ? toupper : tolower)(s[k]);
          }
        s[3] = '\0';
        printf ("%d%d %s\n",
                !strcasecmp (s, "INF"), !strcasecmp (s, "inf"), s);
      }

  return 0;
}

gives:

11 INF
00 ıNF
00 ınF
00 ınf
11 inf
00 İnf
00 İNf
00 İNF

Since the modifications of the string have been done with toupper and
tolower, I would have expected 11 everywhere.

(Probably an upstream bug, but their BTS is currently down.)

-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.9-1-amd64 (SMP w/8 CPU cores)
Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages libc6:amd64 depends on:
ii  libgcc1  1:4.8.1-6

libc6:amd64 recommends no packages.

Versions of packages libc6:amd64 suggests:
ii  debconf [debconf-2.0]  1.5.50
ii  glibc-doc              2.17-7
ii  locales                2.17-7

-- debconf information:
  glibc/upgrade: true
  glibc/disable-screensaver:
  glibc/restart-failed:
* glibc/restart-services: cups cron atd apache2
* libraries/restart-without-asking: false