Problem around brackets, && and ||

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Configuration Information [Automatically generated, do not change]:
Machine: x86_64                                                    
OS: linux-gnu                                                      
Compiler: x86_64-pc-linux-gnu-gcc                                  
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64'
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-pc-linux-gnu'
-DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash'
-DSHELL -DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib 
-DDEFAULT_PATH_VALUE='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'
-DSTANDARD_UTILS_PATH='/bin:/usr/bin:/sbin:/usr/sbin'
-DSYS_BASHRC='/etc/bash/bashrc'
-DSYS_BASH_LOGOUT='/etc/bash/bash_logout' -DNON_INTERACTIVE_LOGIN_SHELLS
-DSSH_SOURCE_BASHRC -O2 -pipe -march=native
-mtune=native                                                                   
             
 
uname output: Linux terminus 2.6.33-gentoo-syrius #1 SMP PREEMPT Fri Feb
26 15:57:48 CET 2010 x86_64 AMD Phenom(tm) 9500 Quad-Core Processor
AuthenticAMD GNU/Linux                                                
Machine Type:
x86_64-pc-linux-gnu                                                             
                                                                                
                                   
 

Bash Version: 4.0
Patch Level: 37  
Release Status: release

Description:
        If the last command in a {...} has && and fails and the {...}
has an || outside then the outside command will be executed.
        This happens not only for {...} but (...) too. I have to add ||
: to the last commands as workaround.                     
        My English is very bad so I wrote some sample code to
demonstrate the problem, and the workaround. I can repeat this under
        Bash version 3
too.                                                                            
                         
 

Repeat-By:

bad.sh:
#!/bin/bash

/bin/true && \
{
        echo "I have to see this"
        /bin/false && echo "I don't have to see this"
} || echo "I never have to see this!"

Outputs:
I have to see this
I never have to see this!

bad2.sh:
#!/bin/bash

/bin/true && \
(
        echo "I have to see this"
        /bin/false && echo "I don't have to see this"
) || echo "I never have to see this!"

Outputs:
I have to see this
I never have to see this!

good.sh:
#!/bin/bash

/bin/true && \
{
        echo "I have to see this"
        /bin/false && echo "I don't have to see this" || :
} || echo "I never have to see this!"

Outputs:
I have to see this