This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [patch] libjava: avoid using escape sequence with undefined behaviour in echo


Paolo Bonzini writes:
> >>>I do think requiring a POSIX-compliant shell is reasonable.
> >>
> >>POSIX compliance wouldn't help much here, since it makes the issue
> >>implementation-defined.  A better alternative might be to use printf
> >>instead.
> > 
> > Agreed; I failed to verify the original claim that ash was non-compliant
> > in this regard.
> 
> I'm sorry for having put out a false claim.  I should have read the 
> standard.  However, this undefined behavior apparently rules out ash 
> from running configure
> 
>      sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{ s//\1/; q; }
>            /^X\(\/\/\)[^/].*/{ s//\1/; q; }
>            /^X\(\/\/\)$/{ s//\1/; q; }
>            /^X\(\/\).*/{ s//\1/; q; }
>            s/.*/./; q'
> 
> (no I don't want to know what this does).

no, it does not, because it doesn't use \1 in an argument to the *echo*
builtin.

  Matthias


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]