Hey Ian thanks for the reply back. Well i have done some more compiling 
and messing with and
this is what i found so far:

This time i did as you said, i piped the compile output to a file using 
the *tee* command.

  ---------------------------- ---------------------------- 
---------------------------- ----------------------------
A.) I cloned a fresh copy of *xen-unstable.hg rev-25376* (5/22/2012) and 
ran:

./configure
sudo make -j5 xen    --> This compiled fine and didn't see any errors
sudo make -j5 tools --> THIS is where all of the errors happen and fail 
to compile

  ---------------------------- ---------------------------- 
---------------------------- ----------------------------
B.) This time i installed the SDL devel package as you suggested and 
cloned another fresh copy of
*xen-unstable.hg rev-25376*

sudo apt-get install libsdl1.2-dev
./configure
sudo make -j5 xen    --> Again, this compiled fine and saw no errors
sudo make -j5 tools --> This time i do not get that error about the 
libSDL BUT i still get other errors
                                             and stops compiling
  ---------------------------- ---------------------------- 
---------------------------- ----------------------------
I have saved the above compile trials to 4 files as the following:

Compiled BEFORE installing libsdl1.2-dev
A - make_xen.log
A - make_tools.log

Compiled AFTER installing libsdl1.2-dev
B - make_xen.log
B - make_tools.log

ALSO, since i didn't want to attach so many large files in a text 
format, i put all 4 files in a TAR.GZ file
and attached that instead.
--------------------------- ---------------------------- 
---------------------------- ----------------------------

So, hopefully this will be helpful to you or to some else in determining 
why, in this case,
*Xen 4.2-unstable REV-25376* is not wanting to compile anymore  .... :)






> On Sun, 2012-05-20 at 17:43 +0100, cyberhawk001@gmail.com wrote:
>>   I have had Xen 4.2-Unstable compiled a week or so ago and it all went
>> fine and running, but i forget what revision i compiled now.
>>
>> When i ran the xl create /etc/xen/win7.cfg to create a VM, i got an
>> error about libxl and running "sudo xl list" shows the newly created
>> VM, SO i just ignored that error for now. That error message was:
>>
>> libxl: error: libxl.c:3117:libxl_sched_credit_domain_set: Cpu weight
>> out of range, valid values are within range from 1 to 65535
> This is a harmless warning and is on our list to fix for 4.2
>
>> ---------------------------------- ----------------------------------
>> ----------------------------------
>>
>> SO, I noticed on the xen-unstable.hg tree that there have been a lot
>> of updates to the libxl lately SO just out of curiosity, i wanted to
>> get the latest revision 25374 of xen-unstable as of today 5/20/2012,
>> and compile it. BUT, i cannot compile Xen anymore as the compile stops
>> with warnings and error messages.
>>
>> Upon scrolling up in the terminal window, i noticed these warning or
>> error messages:
> Thanks, it can be useful for us to see the full context, in which case
> using something like tee(1) to collect the full log and attaching it can
> be useful.
>
>> node-select.c:57:6: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
>> node-select.c: In function ‘vchan_wr’:
>> node-select.c:60:2: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
>> node-select.c: At top level:
>> node-select.c:71:6: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
>> node-select.c: In function ‘stdout_wr’:
>> node-select.c:74:2: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
> These are genuine warnings but aren't causing build failures (I presume
> no -Werror in that subdir).
>
>> The error log from compiling the libSDL test is:
>> /tmp/qemu-conf--3330-.c:1:17: fatal error: SDL.h: No such file or directory
> This means you are missing the SDL development package. I'm not sure if
> this is optional or mandatory, nor whether this message is fatal without
> more context from the build logs.
>
>> ../xen-unstable.hg/tools/qemu-xen-traditional-dir/hw/eepro100.c:1232:5: warning: ‘val’ may be used uninitialized in this function [-Wuninitialized]
>>
>>
>> I also get like a dozen warnings about this:
>> ../tools/xenstore/compat/xs.h:1:2: warning: #warning xs.h is
>> deprecated use xenstore.h instead [-Wcpp]
> These are currently to be expected and are harmless.
>
>> AND finally the compilations stops with these messages:
>> libxl.c: In function ‘libxl_primary_console_exec’:
>> libxl.c:1233:9: error: case value ‘4294967295’ not in enumerated type
>> ‘libxl_domain_type’ [-Werror=switch]
> This one is known and a fix is in progress. It's most likely this one
> which is causing the actual build error.
>
> This slipped through our testing net due to various compiler versions
> being cleverer/stupider than others and so trigger more or less
> warnings, this one happens only with a more modern gcc than what our
> test system uses.
>
> Ian.
>
>
>