gcc 4.0.0 Ada build

[Duncan Sands]

> When configuring I used
> 
>     --enable-threads=gnat
> 
> but when the build errors off I'm told "gnat is an unknown thread  
> package".

Maybe the following documentation patch should be applied:

--- configure.html.orig	2005-05-28 22:49:32.466872948 +0200
+++ configure.html	2005-05-28 22:50:56.666117558 +0200
@@ -473,11 +473,6 @@ like C++ and Java.  The possibilities fo
           <dl>
 <dt><code>aix</code><dd>AIX thread support. 
 <br><dt><code>dce</code><dd>DCE thread support. 
-<br><dt><code>gnat</code><dd>Ada tasking support.  For non-Ada programs, this setting is equivalent
-to `<samp><span class="samp">single</span></samp>'.  When used in conjunction with the Ada run time, it
-causes GCC to use the same thread primitives as Ada uses.  This option
-is necessary when using both Ada and the back end exception handling,
-which is the default for most Ada targets. 
 <br><dt><code>mach</code><dd>Generic MACH thread support, known to work on NeXTSTEP.  (Please note
 that the file needed to support this configuration, <samp><span class="file">gthr-mach.h</span></samp>, is
 missing and thus this setting will cause a known bootstrap failure.) 
@@ -582,7 +577,6 @@ their runtime libraries should be built.
      <p>Currently, you can use any of the following:
 <code>all</code>, <code>ada</code>, <code>c</code>, <code>c++</code>, <code>f95</code>, <code>java</code>,
 <code>objc</code>, <code>obj-c++</code>, <code>treelang</code>. 
-Building the Ada compiler has special requirements, see below. 
 If you do not pass this flag, or specify the option <code>all</code>, then all
 default languages available in the <samp><span class="file">gcc</span></samp> sub-tree will be configured. 
 Ada, Objective-C++, and treelang are not default languages; the rest are.