Fix for #107950, Debian BTS #516152, #343673 and Ubuntu LP: #589496

[Rodrigo Silva]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-pc-linux-gnu' -D$
uname output: Linux desktop 2.6.35-32-generic #64-Ubuntu SMP Tue Jan 3 00:47:07 
UTC 2012 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu

Bash Version: 4.1
Patch Level: 5
Release Status: release

Description:
        Debian's bash (compiled with -DSYS_BASHRC) documentation says
          "--rcfile file: Execute commands from file instead of the system wide 
initialization
          file /etc/bash.bashrc and the standard personal initialization file 
~/.bashrc
          if the shell is interactive."

        But testing shows that /etc/bash.bashrc is being executed even when 
--rcfile is used.

        So the only way for the user to disable the system-wide rc is to use 
the --norc option,
         which also disables both ~/.bashrc and any custom rc specified in 
--rcfile

        User should be able to prevent system rc and selecting a custom rc by 
using the --rcfile option,
         as per the documentation.

Repeat-By:
        from any terminal:
        $ sudo echo "echo systemrc" > /etc/bash.bashrc
        $ echo "echo customrc" > ~/customrc
        $ echo "echo bashrc" > ~/.bashrc
        $ bash
        systemrc
        bashrc
        $ bash --rcfile ~/customrc --norc
        $

        Current behavior:
        $ bash --rcfile ~/customrc
        systemrc
        customrc
        $

        Expected behavior:
        $ bash --rcfile ~/customrc
        customrc
        $

Fix:
        To fix the behavior so it matches the documentation, SYS_BASHRC should 
only
        be executed if --rcfile is NOT used.
        
        Also, documentation should be updated to clarify that --norc option 
disables
         --rcfile option.
         
        Last but not least, -DSYS_BASHRC compile option should be properly 
documented,
         or at least included in configure options (as in 
--enable-system-bashrc)
        
        The attached files are:
        0000-xxx.patch: enables SYS_BASHRC so bug can be reproduced and the fix 
can be tested
        0001-xxx.patch: Fixes the bug. This is the ONLY patch meant for merge.
        
        They were succesfully tested on git "master" branch (4.2 patchlevel 20)

Sincerely,
Rodrigo Silva (MestreLion in Launchpad)

0000-SYS_BASHRC-enabled-in-config-top.h.patch
Description: Binary data

0001-SYS_BASHRC-do-not-execute-etc-bash.bashrc-if-rcfile-is-set.patch
Description: Binary data