Re: [bug-libunistring] Fix quoting in exported.sh.in, allow multiple arguments.

[Ralf Wildenhues]

Hi Bruno,

* Bruno Haible wrote on Fri, May 01, 2009 at 01:53:04PM CEST:
> > Quote argument to eval, to avoid losing TABs from @GLOBAL_SYMBOL_PIPE@
> 
> Hmm. I used exactly the same kind of quoting as libtool. Namely, the
> configure file contains the following code, expanded from libtool.m4:

>     if { (eval echo "$as_me:$LINENO: \"$NM conftest.$ac_objext \| 
> $lt_cv_sys_global_symbol_pipe \> $nlist\"") >&5
>   (eval $NM conftest.$ac_objext \| $lt_cv_sys_global_symbol_pipe \> $nlist) 
> 2>&5

Thanks!  Guess that should be fixed then, too.  Of course it also pretty
much proves that no nm implementation really uses leading TABs in their
output.

> Regarding quoting, probably I need to avoid evaluating the argument
> string, i.e. write

Yeah, probably something like

  nm_cmd="@NM@ \"address@hidden" | @GLOBAL_SYMBOL_PIPE@"

One of the rules of thumb that I've started to follow is that, unless
one specifically uses eval to flatten whitespace in some variable, then
it is always better to double-quote any variable expansions after eval.
(Just like you double-quote 'case' arguments ;-)

> > The multi-file change allows for further improvements to the build
> > system.
> 
> What other changes do you have in mind? Or do you want to reuse exported.sh
> in automake?

I'm still working on the other patch to allow fully parallel build in
this directory.  Fine with me if you postpone the exported.sh change
until then; or maybe it won't even be needed.

Cheers,
Ralf