Re: [PATCH 2/5] docs: mention cost of globbing during variable expansion

[Ralf Wildenhues]

Hi Eric,

* Eric Blake wrote on Thu, Aug 26, 2010 at 01:18:18AM CEST:
> * doc/autoconf.texi (Shell Substitutions) <${var=literal}>:
> Recommend quoting substitutions that might trigger globbing.
> (Limitations of Builtins) <:>: Likewise.
> * bin/autoconf.as: Follow our own advice.
> * lib/autoconf/functions.m4 (AC_FUNC_SELECT_ARGTYPES): Likewise.
> * lib/autoconf/general.m4 (_AC_INIT_PARSE_ARGS): Likewise.
> * lib/autoconf/status.m4 (AC_OUTPUT): Likewise.
> * lib/autotest/general.m4 (_AT_FINISH): Likewise.
> * lib/m4sugar/m4sh.m4 (AS_TMPDIR): Likewise.
> * tests/autotest.at (parallel autotest and signal handling):
> Likewise.
> * tests/c.at (AC_OPENMP and C, AC_OPENMP and C++): Likewise.
> * tests/foreign.at (shtool): Likewise.
> * tests/fortran.at: Likewise.
> * tests/tools.at (autom4te preselections): Likewise.
> * tests/torture.at (VPATH): Likewise.

while you found most bugs in the code part of this patch already, ...

>  2010-08-25  Eric Blake  <address@hidden>
> 
> +       docs: mention cost of globbing during variable expansion
> [...]
> +
> +2010-08-25  Eric Blake  <address@hidden>
> +
>         m4sh: fix some namespace safety issues

... and somebody should fix git-merge-changelog adding extra header
lines ...

> --- a/doc/autoconf.texi
> +++ b/doc/autoconf.texi
[...]

> @@ -15441,7 +15467,7 @@ Shell Substitutions
> 
>  @example
>  default="yu,yaa"
> -: address@hidden"$default"@}
> +: "address@hidden"$default"@}"
>  @end example
> 
>  @noindent
> @@ -15467,7 +15493,7 @@ Shell Substitutions
> 
>  @example
>  default="a b c"
> -: address@hidden"$default"@}
> +: "address@hidden"$default"@}"
>  for c in $list; do
>    echo $c
>  done
> @@ -15720,7 +15746,7 @@ Assignments
>  brace, use:
> 
>  @example
> -: address@hidden'my literal'@}
> +: "address@hidden'my literal'@}"
>  @end example
> 
>  @item
> @@ -15729,7 +15755,7 @@ Assignments
>  (i.e., it's not a list), then use:
> 
>  @example
> -: address@hidden"$default"@}
> +: "address@hidden"$default"@}"
>  @end example
> 
>  @item

... it doesn't look to safe to change code snippets in the manual that
describe quoting bugs in old shells, which is true for at least some of
the above.  I don't know if you've fixed all instances in followup
patches already, but at least I haven't seen a log entry that states
this.

> --- a/lib/autoconf/functions.m4
> +++ b/lib/autoconf/functions.m4
> @@ -1453,7 +1453,7 @@ AC_CACHE_CHECK([types of arguments for select],
>   done
>  done
>  # Provide a safe default value.
> -: ${ac_cv_func_select_args='int,int *,struct timeval *'}
> +: "${ac_cv_func_select_args='int,int *,struct timeval *'}"

This one looks buggy too (and is not reverted yet).

Cheers,
Ralf