Re: [PATCH] nl_langinfo: avoid configure-time syntax error

[Paolo Bonzini]

On 01/04/2010 03:03 PM, Jim Meyering wrote:
> Testing my proposed make-regex-use-nl_langinfo changes,
> I encountered this configure failure:
>      ...
>      checking whether<netinet/in.h>  is self-contained... yes
>      ./configure: line 31968: syntax error near unexpected token `else'
>      ./configure: line 31968: `  else'
>
> It was due to this syntax error:
>
>      if test $HAVE_LANGINFO_H = 1; then
>
>      else
>        ac_cv_func_nl_langinfo=no
>      fi
>
> Here's the work-around.
> However, it would be far better if AC_CHECK_FUNCS_ONCE
> were to expand to e.g., ":" rather than the empty string,
> so that it can be used unadorned in situations like the above.
> Otherwise, it looks like a pitfall designed to trap the uninitiated.
>
> Bruno, ok to apply?

No, AC_CHECK_FUNCS_ONCE should _always_ expand to an empty string.  The 
test is done always---and it is done outside the macro.  It's clearer to 
do as in the attached patch.  Bruno, is this okay?

Paolo

nl-langinfo.patch
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