Bug#312036: libc6: Valgrind reports invalid memory access for printf("%1$e", 1.);

[Justin Pryzby <justinpryzby@users.sourceforge.net>]

Package: libc6
Version: 2.3.2.ds1-21
Severity: normal
Tags: security

The C program:

  #include <stdio.h>
  int main()
  {
  	printf("%1$e", 1.);
  	return 0;
  }

Compiled with: gcc -O3 -W -Wall pf.c

Using: gcc version 3.3.5 (Debian 1:3.3.5-12)

It correctly prints: 1.000000e+00

Yet, valgrind reports: 
 Conditional jump or move depends on uninitialised value(s)
    at 0x1B966666: __printf_fp (in /lib/tls/libc-2.3.2.so)
    by 0x1B963D7B: vfprintf (in /lib/tls/libc-2.3.2.so)
    by 0x1B96A8C1: printf (in /lib/tls/libc-2.3.2.so)
    by 0x80483AA: main (in /home/pryzbyj/programming_andromeda/matchstars/a.out)

Tagged security because invalid memory access seems a potential
problem.  Untag it if you know more than I do, and can show that it is
not.

-- System Information:
Debian Release: 3.1
  APT prefers testing
  APT policy: (101, 'testing'), (99, 'unstable'), (9, 'experimental')
Architecture: i386 (i686)
Kernel: Linux 2.6.11.7Y
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)

Versions of packages libc6 depends on:
ii  libdb1-compat                 2.1.3-7    The Berkeley database routines [gl

-- no debconf information