From: Charles Mills <cmills@...>
Date: 2004-07-30T23:50:23+09:00
Subject: Re: mkmf.rb


On Jul 30, 2004, at 2:56 AM, nobu.nokada@softhome.net wrote:

> Hi,
>
> At Sat, 24 Jul 2004 01:14:17 +0900,
> Charles Mills wrote in [ruby-talk:107305]:
>> Also I have been using this function to determine the byte order,
>> perhaps it would be useful to somebody.
>
> Running compiled file can't work for cross compiling.
>
> 
> Index: lib/mkmf.rb
> ===================================================================
> RCS file: /cvs/ruby/src/ruby/lib/mkmf.rb,v
> retrieving revision 1.194
> diff -u -2 -p -r1.194 mkmf.rb
> --- lib/mkmf.rb	13 Jul 2004 06:51:26 -0000	1.194
> +++ lib/mkmf.rb	30 Jul 2004 09:51:23 -0000
> @@ -266,6 +266,10 @@ ensure
>  end
>
> -def try_compile(src, opt="", &b)
> +def try_compile0(src, opt="", &b)
>    try_do(src, cc_command(opt), &b)
> +end
> +
> +def try_compile(src, opt="", &b)
> +  try_do(src, opt, &b)
>  ensure
>    rm_f "conftest*"
> @@ -623,4 +627,20 @@ def find_executable(bin, path = nil)
>  end
>
> +def byte_order
> +  try_compile0 %{
> +#include <stdio.h>
> +volatile short be[] = { 0, 0x4249, 0x4765, 0x6E44, 0x6961, 0x6E53, 
> 0x7953, 0 };
> +volatile short le[] = { 0, 0x694C, 0x5454, 0x656C, 0x6E45, 0x6944, 
> 0x6E61, 0 };
> +}
> +  case open(CONFTEST_C.sub(/\.c$/, '.'+CONFIG['OBJEXT']), 
> 'rb'){|f|f.read}
> +  when /\0BIGenDianSyS\0/
> +    :big
> +  when /\0LiTTleEnDian\0/
> +    :little
> +  end
> +ensure
> +  rm_f "conftest*"
> +end
> +
>  def arg_config(config, default=nil)
>    $configure_args.fetch(config, default)
> 
Very nice - just trying to understand this, are you greping the object 
code?
-Charlie

>
> -- 
> Nobu Nakada
>
>