'ccache gcc' as compiler with libtool

[Vincent Caron <v dot caron at zerodeux dot net>]

Hello,

   I'm running automake 1.7.9 as packaged in Sid, and having trouble
using 'cache gcc' as compiler. I get this error :

/bin/sh ../libtool --mode=link ccache g++  -Wall [...]
libtool: link: unable to infer tagged configuration
libtool: link: specify a tag with `--tag'


   As far as I could see, libtool extract the compiler name from the
first non-option argument, and stop parsing from here. So it identifies
the compiler (his internal var is base_compile) as 'ccache', and fails.

   Since Libtool is not 'wrong' and I don't see good ways to change its
command line parsing without breaking it, I chose to quote the compiler
name in automake invocations of libtool. I hope this 3-liner patch is
useful.

2123c2123
< 	    my $obj_ltcompile = '$(LIBTOOL) --mode=compile ' . $obj_compile;
---
> 	    my $obj_ltcompile = "\$(LIBTOOL) --mode=compile \"$obj_compile\"";
7501c7501
<     &define_variable ("LT$var", "\$(LIBTOOL) --mode=compile $value")
---
>     &define_variable ("LT$var", "\$(LIBTOOL) --mode=compile \"$value\"")
7520c7520
< 		       . $lang->link));
---
> 		       . "\"$lang->link\""));