[ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[SourceForge.net]

Bugs item #1807620, was opened at 2007-10-04 18:25
Message generated for change (Tracker Item Submitted) made by Item Submitter
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: None
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Technologov (technologov)
Assigned to: Nobody/Anonymous (nobody)
Summary: KVM's --disable-gcc-check doesn't work

Initial Comment:
KVM's configure switch: "--disable-gcc-check" doesn't work.

This bug makes KVM very hard to compile on openSUSE 10.2/10.3, which, unlike Fedora doesn't have compat-gcc-34 package.

Here is the error:

alexey@suse103-home:~/Linstall/kvm-45> ./configure --disable-gcc-check
./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc

According to HELP, it should work:
alexey@suse103-home:~/Linstall/kvm-45> ./configure --help
Usage: ./configure [options]

Options include:

    --prefix=PREFIX        where to install things (/usr/local)
    --with-patched-kernel  don't use external module
    --kerneldir=DIR        kernel build directory (/lib/modules/2.6.22.5-31-bigsmp/build)
    --qemu-cc=""   compiler for qemu (needs gcc3.x) ()
    --disable-gcc-check    don't insist on gcc-3.x
                                   - this will break running without kvm


Host: openSUSE 10.3, 32-bit, Intel Core 2 CPU, KVM-45.

-Alexey Technologov

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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Farkas Levente]

hi,
what's the real reason that kvm can't be compiled gcc-4.x?
wouldn't it be better to be able to compile with the current compilers too?

SourceForge.net wrote:
> Bugs item #1807620, was opened at 2007-10-04 18:25
> Message generated for change (Tracker Item Submitted) made by Item Submitter
> You can respond by visiting: 
> https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599
> 
> Please note that this message will contain a full copy of the comment thread,
> including the initial issue submission, for this request,
> not just the latest update.
> Category: None
> Group: None
> Status: Open
> Resolution: None
> Priority: 5
> Private: No
> Submitted By: Technologov (technologov)
> Assigned to: Nobody/Anonymous (nobody)
> Summary: KVM's --disable-gcc-check doesn't work
> 
> Initial Comment:
> KVM's configure switch: "--disable-gcc-check" doesn't work.
> 
> This bug makes KVM very hard to compile on openSUSE 10.2/10.3, which, unlike Fedora doesn't have compat-gcc-34 package.
> 
> Here is the error:
> 
> alexey@suse103-home:~/Linstall/kvm-45> ./configure --disable-gcc-check
> ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc
> 
> According to HELP, it should work:
> alexey@suse103-home:~/Linstall/kvm-45> ./configure --help
> Usage: ./configure [options]
> 
> Options include:
> 
>     --prefix=PREFIX        where to install things (/usr/local)
>     --with-patched-kernel  don't use external module
>     --kerneldir=DIR        kernel build directory (/lib/modules/2.6.22.5-31-bigsmp/build)
>     --qemu-cc=""   compiler for qemu (needs gcc3.x) ()
>     --disable-gcc-check    don't insist on gcc-3.x
>                                    - this will break running without kvm
> 
> 
> Host: openSUSE 10.3, 32-bit, Intel Core 2 CPU, KVM-45.
> 
> -Alexey Technologov
> 
> ----------------------------------------------------------------------
> 
> You can respond by visiting: 
> https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599
> 
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> 


-- 
  Levente                               "Si vis pacem para bellum!"

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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Gregory Haskins]

[-- Attachment #1.1: Type: text/plain, Size: 3250 bytes --]

On Thu, 2007-10-04 at 18:33 +0200, Farkas Levente wrote:
> hi,
> what's the real reason that kvm can't be compiled gcc-4.x?
> wouldn't it be better to be able to compile with the current compilers too?

Its actually an issue with QEMUs cpu emulation code.  It takes advantage
of compiler traits that are no longer true in the 4.x series.  The code
will actually compile under 4.x however.  It just will not run properly.
However, KVM doesn't use QEMUs cpu emulation, so if you do not care
about running with KVM disabled (e.g. -no-kvm), you don't technically
need to worry about it.

Hope that helps.
-Greg

> 
> SourceForge.net wrote:
> > Bugs item #1807620, was opened at 2007-10-04 18:25
> > Message generated for change (Tracker Item Submitted) made by Item Submitter
> > You can respond by visiting: 
> > https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599
> > 
> > Please note that this message will contain a full copy of the comment thread,
> > including the initial issue submission, for this request,
> > not just the latest update.
> > Category: None
> > Group: None
> > Status: Open
> > Resolution: None
> > Priority: 5
> > Private: No
> > Submitted By: Technologov (technologov)
> > Assigned to: Nobody/Anonymous (nobody)
> > Summary: KVM's --disable-gcc-check doesn't work
> > 
> > Initial Comment:
> > KVM's configure switch: "--disable-gcc-check" doesn't work.
> > 
> > This bug makes KVM very hard to compile on openSUSE 10.2/10.3, which, unlike Fedora doesn't have compat-gcc-34 package.
> > 
> > Here is the error:
> > 
> > alexey@suse103-home:~/Linstall/kvm-45> ./configure --disable-gcc-check
> > ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc
> > 
> > According to HELP, it should work:
> > alexey@suse103-home:~/Linstall/kvm-45> ./configure --help
> > Usage: ./configure [options]
> > 
> > Options include:
> > 
> >     --prefix=PREFIX        where to install things (/usr/local)
> >     --with-patched-kernel  don't use external module
> >     --kerneldir=DIR        kernel build directory (/lib/modules/2.6.22.5-31-bigsmp/build)
> >     --qemu-cc=""   compiler for qemu (needs gcc3.x) ()
> >     --disable-gcc-check    don't insist on gcc-3.x
> >                                    - this will break running without kvm
> > 
> > 
> > Host: openSUSE 10.3, 32-bit, Intel Core 2 CPU, KVM-45.
> > 
> > -Alexey Technologov
> > 
> > ----------------------------------------------------------------------
> > 
> > You can respond by visiting: 
> > https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599
> > 
> > -------------------------------------------------------------------------
> > This SF.net email is sponsored by: Splunk Inc.
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> > kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
> > https://lists.sourceforge.net/lists/listinfo/kvm-devel
> > 
> 
> 

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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Farkas Levente]

Gregory Haskins wrote:
> On Thu, 2007-10-04 at 18:33 +0200, Farkas Levente wrote:
>> hi,
>> what's the real reason that kvm can't be compiled gcc-4.x?
>> wouldn't it be better to be able to compile with the current compilers too?
> 
> Its actually an issue with QEMUs cpu emulation code.  It takes advantage
> of compiler traits that are no longer true in the 4.x series.  The code
> will actually compile under 4.x however.  It just will not run properly.
> However, KVM doesn't use QEMUs cpu emulation, so if you do not care
> about running with KVM disabled (e.g. -no-kvm), you don't technically
> need to worry about it.

ok but now as qemu code was imported into kvm, then it's probably would
be better to witch gcc-4.x?

-- 
  Levente                               "Si vis pacem para bellum!"

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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Gregory Haskins]

[-- Attachment #1.1: Type: text/plain, Size: 360 bytes --]

On Thu, 2007-10-04 at 19:27 +0200, Farkas Levente wrote:

> ok but now as qemu code was imported into kvm, then it's probably would
> be better to witch gcc-4.x?

Sure.  Are you volunteering? ;)  I'm sure both upstream QEMU developers,
KVM developers, and the community using either would be most
appreciative.  I know I would be.

Regards,
-Greg


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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Farkas Levente]

Gregory Haskins wrote:
> On Thu, 2007-10-04 at 19:27 +0200, Farkas Levente wrote:
> 
>> ok but now as qemu code was imported into kvm, then it's probably would
>> be better to witch gcc-4.x?
> 
> Sure.  Are you volunteering? ;)  I'm sure both upstream QEMU developers,
> KVM developers, and the community using either would be most
> appreciative.  I know I would be.

here i mean that packaging kvm for fedora/redhat/centos using gcc-4.x in
stead of gcc-3.x. if currently there is no reason to use gcc-3.x than i
change all of my spec file.

ps. anyway it's planed to be temporary or permanent to use a qemu fork
for kvm and not try to propagate changes back to the upstream qemu?

-- 
  Levente                               "Si vis pacem para bellum!"

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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Gregory Haskins]

[-- Attachment #1.1: Type: text/plain, Size: 1346 bytes --]

On Thu, 2007-10-04 at 21:49 +0200, Farkas Levente wrote:
> Gregory Haskins wrote:
> > On Thu, 2007-10-04 at 19:27 +0200, Farkas Levente wrote:
> > 
> >> ok but now as qemu code was imported into kvm, then it's probably would
> >> be better to witch gcc-4.x?
> > 
> > Sure.  Are you volunteering? ;)  I'm sure both upstream QEMU developers,
> > KVM developers, and the community using either would be most
> > appreciative.  I know I would be.
> 
> here i mean that packaging kvm for fedora/redhat/centos using gcc-4.x in
> stead of gcc-3.x. if currently there is no reason to use gcc-3.x than i
> change all of my spec file.

You *could*, sure.  I have done this for local builds here.  But if you
go that route I would recommend making a patch to KVM so it doesn't fall
back into QEMU mode automatically (today if it can't open the kvm module
it will assume "-no-kvm" like behavior).  Otherwise you will have a
bunch of support calls about why its not working properly should someone
cause the system to fall back.

> 
> ps. anyway it's planed to be temporary or permanent to use a qemu fork
> for kvm and not try to propagate changes back to the upstream qemu?

Ill defer to Avi here, though as I understand it: Things that benefit
the upstream source get pushed...things that are KVM only don't.

Regards,
-Greg

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[RFC] let kvm be compiled with gcc4 and prevent users to shoot themselves in the foot while doing so (was Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work)

[Carlo Marcelo Arenas Belon]

On Thu, Oct 04, 2007 at 04:39:30PM -0400, Gregory Haskins wrote:
> On Thu, 2007-10-04 at 21:49 +0200, Farkas Levente wrote:
> > 
> > here i mean that packaging kvm for fedora/redhat/centos using gcc-4.x in
> > stead of gcc-3.x. if currently there is no reason to use gcc-3.x than i
> > change all of my spec file.
> 
> You *could*, sure.  I have done this for local builds here.  But if you
> go that route I would recommend making a patch to KVM so it doesn't fall
> back into QEMU mode automatically (today if it can't open the kvm module
> it will assume "-no-kvm" like behavior).  Otherwise you will have a
> bunch of support calls about why its not working properly should someone
> cause the system to fall back.

And considering also there might be other yet unknown bugs because of gcc4, it
is most likely better to stick to use gcc-3.x, unless there is really no other
option.

For cases where no compat-gcc package is provided (like in OpenSUSE) then the
following is IMHO the next best approach to force users to get gcc-3.x
compiler installed from source just to be able to compile kvm.

Carlo

PS. please let me know what you think about it and if interested so I can
provide the 3 patches (or more if more changes are needed) in a [PATCH] 
series for easy git-am'ing

---
diff --git a/configure b/configure
index d9292fe..33a56d2 100755
--- a/configure
+++ b/configure
@@ -63,8 +63,12 @@ while [[ "$1" = -* ]]; do
 done
 
 if [[ -z "$qemu_cc" ]]; then
-    echo "$0: cannot locate gcc 3.x. please install it or specify with --qemu-cc"
-    exit 1
+    if [[ -z "$disable_gcc_check" ]]; then
+        echo "$0: cannot locate gcc 3.x. please install it or specify with --qemu-cc"
+        exit 1
+    else
+        qemu_cc=gcc
+    fi
 fi
 
 libkvm_kerneldir="$kerneldir"
diff --git a/qemu/configure b/qemu/configure
index fc1e59a..15549e3 100755
--- a/qemu/configure
+++ b/qemu/configure
@@ -1022,6 +1022,11 @@ if test "$target_cpu" = "i386" ; then
   if test $kqemu = "yes" -a "$target_softmmu" = "yes" -a $cpu = "i386" ; then
     echo "#define USE_KQEMU 1" >> $config_h
   fi
+  if test $check_gcc = "no" ; then
+    if gcc -v 2>&1 | grep -q 'gcc *version *4\.[0-3]\.[0-9]'; then
+      echo "#define USE_GCC4 1" >> $config_h
+    fi
+  fi
   configure_kvm
 elif test "$target_cpu" = "arm" -o "$target_cpu" = "armeb" ; then
   echo "TARGET_ARCH=arm" >> $config_mak
@@ -1059,6 +1064,11 @@ elif test "$target_cpu" = "x86_64" ; then
   if test $kqemu = "yes" -a "$target_softmmu" = "yes" -a $cpu = "x86_64"  ; then
     echo "#define USE_KQEMU 1" >> $config_h
   fi
+  if test $check_gcc = "no" ; then
+    if gcc -v 2>&1 | grep -q 'gcc *version *4\.[0-3]\.[0-9]'; then
+      echo "#define USE_GCC4 1" >> $config_h
+    fi
+  fi
   configure_kvm
 elif test "$target_cpu" = "mips" -o "$target_cpu" = "mipsel" ; then
   echo "TARGET_ARCH=mips" >> $config_mak
diff --git a/qemu/vl.c b/qemu/vl.c
index fe49d2c..2f78955 100644
--- a/qemu/vl.c
+++ b/qemu/vl.c
@@ -8421,8 +8421,13 @@ int main(int argc, char **argv)
 #endif
 #ifdef USE_KVM
 	    case QEMU_OPTION_no_kvm:
+#ifdef USE_GCC4
+		fprintf(stderr, "Can't run without kvm if compiled with gcc4\n");
+		exit(1);
+#else
 		kvm_allowed = 0;
 		break;
+#endif
 	    case QEMU_OPTION_no_kvm_irqchip:
 		kvm_irqchip = 0;
 		break;
@@ -8552,8 +8557,13 @@ int main(int argc, char **argv)
 #if USE_KVM
     if (kvm_allowed) {
 	if (kvm_qemu_init() < 0) {
+#if USE_GCC4
+	    fprintf(stderr, "Could not initialize KVM, can't run without kvm if compiled with gcc4\n");
+	    exit(1);
+#else
 	    fprintf(stderr, "Could not initialize KVM, will disable KVM support\n");
 	    kvm_allowed = 0;
+#endif
 	}
     }
 #endif

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Re: [RFC] let kvm be compiled with gcc4 and prevent users to shoot themselves in the foot while doing so (was Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work)

[Jim Paris]

Carlo Marcelo Arenas Belon wrote:
> And considering also there might be other yet unknown bugs because of gcc4, it
> is most likely better to stick to use gcc-3.x, unless there is really no other
> option.
> 
> For cases where no compat-gcc package is provided (like in OpenSUSE) then the
> following is IMHO the next best approach to force users to get gcc-3.x
> compiler installed from source just to be able to compile kvm.

This will probably become more of a problem over time.  GCC 3 is
slated to be removed from the next Debian release:
  http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=440425
  http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=440430

> PS. please let me know what you think about it and if interested so I can
> provide the 3 patches (or more if more changes are needed) in a [PATCH] 
> series for easy git-am'ing
> 
> +  if test $check_gcc = "no" ; then
> +    if gcc -v 2>&1 | grep -q 'gcc *version *4\.[0-3]\.[0-9]'; then
> +      echo "#define USE_GCC4 1" >> $config_h
> +    fi
> +  fi

Something like

#if __GNUC__ >= 4

in the code would be simpler.

-jim

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Re: [RFC] let kvm be compiled with gcc4 and prevent users to shoot themselves in the foot while doing so (was Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work)

[Carlo Marcelo Arenas Belon]

On Sun, Oct 07, 2007 at 06:18:27PM -0400, Jim Paris wrote:
> > +  if test $check_gcc = "no" ; then
> > +    if gcc -v 2>&1 | grep -q 'gcc *version *4\.[0-3]\.[0-9]'; then
> > +      echo "#define USE_GCC4 1" >> $config_h
> > +    fi
> > +  fi
> 
> Something like
> 
> #if __GNUC__ >= 4
> 
> in the code would be simpler.

really good idea; and also as a side effect makes the patches independent as
there is no need to have that qemu's configure glue anymore.

Carlo

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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Avi Kivity]

Farkas Levente wrote:
> ps. anyway it's planed to be temporary or permanent to use a qemu fork
> for kvm and not try to propagate changes back to the upstream qemu?
>   

The plan is to submit everything to upstream qemu.

-- 
Any sufficiently difficult bug is indistinguishable from a feature.


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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Bernhard Kaindl]

On Thu, 4 Oct 2007, Gregory Haskins wrote:
> On Thu, 2007-10-04 at 19:27 +0200, Farkas Levente wrote:
>
>> ok but now as qemu code was imported into kvm, then it's probably would
>> be better to witch gcc-4.x?
>
> Sure.  Are you volunteering? ;)  I'm sure both upstream QEMU developers,
> KVM developers, and the community using either would be most
> appreciative.  I know I would be.

Here is a discussion thread about a patch by Michael Matz to make qemu's
CPU emulation code actually work with gcc4:

http://www.nabble.com/-patch--make-qemu-work-with-GCC-4-t4345765.html

It's against the current qemu CVS, so as Avi updated kvm to qemu CVS now,
it might be worth a try.

It means that the CPU emulation incurs a 3% performance regression, but
the CPU emulation is only used when the CPU is not emulated by KVM in
the kernel, so it should be a not a big concern for KVM, and if gcc4
would compile more efficent code for the device emulatoin, it could
even lead to a theoritical speedup when KVM does CPU emulation, but
that is a pure theory.

In this mail (which you do not see in the above thread view), a
git repository with cumulated changes for qemu with gcc4 is mentioned,
it seems to have further fixes on top of the initial patch:

http://www.mail-archive.com/qemu-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org/msg12017.html

Bernhard Kaindl

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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[Anthony Liguori]

Gregory Haskins wrote:
> On Thu, 2007-10-04 at 18:33 +0200, Farkas Levente wrote:
>   
>> hi,
>> what's the real reason that kvm can't be compiled gcc-4.x?
>> wouldn't it be better to be able to compile with the current compilers too?
>>     
>
> Its actually an issue with QEMUs cpu emulation code.  It takes advantage
> of compiler traits that are no longer true in the 4.x series.  The code
> will actually compile under 4.x however.  It just will not run properly.
> However, KVM doesn't use QEMUs cpu emulation, so if you do not care
> about running with KVM disabled (e.g. -no-kvm), you don't technically
> need to worry about it.
>   

FWIW, there are patches that allow QEMU to compile and work with GCC 4 
but, so far, certain folks in the QEMU community have objected strongly 
to them (look for the threads about post-processing GCC assembly output).

Those patches do work with KVM (and -no-kvm still works).  However, it 
would be a bad idea to apply them to the KVM QEMU tree b/c it would make 
merging in the future much more difficult.

Regards,

Anthony Liguori

> Hope that helps.
> -Greg
>
>   
>> SourceForge.net wrote:
>>     
>>> Bugs item #1807620, was opened at 2007-10-04 18:25
>>> Message generated for change (Tracker Item Submitted) made by Item Submitter
>>> You can respond by visiting: 
>>> https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599
>>>
>>> Please note that this message will contain a full copy of the comment thread,
>>> including the initial issue submission, for this request,
>>> not just the latest update.
>>> Category: None
>>> Group: None
>>> Status: Open
>>> Resolution: None
>>> Priority: 5
>>> Private: No
>>> Submitted By: Technologov (technologov)
>>> Assigned to: Nobody/Anonymous (nobody)
>>> Summary: KVM's --disable-gcc-check doesn't work
>>>
>>> Initial Comment:
>>> KVM's configure switch: "--disable-gcc-check" doesn't work.
>>>
>>> This bug makes KVM very hard to compile on openSUSE 10.2/10.3, which, unlike Fedora doesn't have compat-gcc-34 package.
>>>
>>> Here is the error:
>>>
>>> alexey@suse103-home:~/Linstall/kvm-45> ./configure --disable-gcc-check
>>> ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc
>>>
>>> According to HELP, it should work:
>>> alexey@suse103-home:~/Linstall/kvm-45> ./configure --help
>>> Usage: ./configure [options]
>>>
>>> Options include:
>>>
>>>     --prefix=PREFIX        where to install things (/usr/local)
>>>     --with-patched-kernel  don't use external module
>>>     --kerneldir=DIR        kernel build directory (/lib/modules/2.6.22.5-31-bigsmp/build)
>>>     --qemu-cc=""   compiler for qemu (needs gcc3.x) ()
>>>     --disable-gcc-check    don't insist on gcc-3.x
>>>                                    - this will break running without kvm
>>>
>>>
>>> Host: openSUSE 10.3, 32-bit, Intel Core 2 CPU, KVM-45.
>>>
>>> -Alexey Technologov
>>>
>>> ----------------------------------------------------------------------
>>>
>>> You can respond by visiting: 
>>> https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599
>>>
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>>>       
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Re: [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn'twork

[Itamar Heim]

This is a solution to the original problem with opensuse:

You can get gcc33 from the opensuse build service (this is the new
one-click-install)
http://software.opensuse.org/ymp/devel%3Atools%3Agcc/openSUSE_10.3/i586/
gcc33-3.3.3-41.6.i586.rpm.ymp

(or download specific rpm's from http://software.opensuse.org/search by
searching for gcc33).

Itamar

-----Original Message-----
From: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
[mailto:kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org] On Behalf Of
SourceForge.net
Sent: Thursday, October 04, 2007 6:26 PM
To: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
Subject: [kvm-devel] [ kvm-Bugs-1807620 ] KVM's --disable-gcc-check
doesn'twork

Bugs item #1807620, was opened at 2007-10-04 18:25
Message generated for change (Tracker Item Submitted) made by Item
Submitter
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&gro
up_id=180599

Please note that this message will contain a full copy of the comment
thread,
including the initial issue submission, for this request,
not just the latest update.
Category: None
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Technologov (technologov)
Assigned to: Nobody/Anonymous (nobody)
Summary: KVM's --disable-gcc-check doesn't work

Initial Comment:
KVM's configure switch: "--disable-gcc-check" doesn't work.

This bug makes KVM very hard to compile on openSUSE 10.2/10.3, which,
unlike Fedora doesn't have compat-gcc-34 package.

Here is the error:

alexey@suse103-home:~/Linstall/kvm-45> ./configure --disable-gcc-check
./configure: cannot locate gcc 3.x. please install it or specify with
--qemu-cc

According to HELP, it should work:
alexey@suse103-home:~/Linstall/kvm-45> ./configure --help
Usage: ./configure [options]

Options include:

    --prefix=PREFIX        where to install things (/usr/local)
    --with-patched-kernel  don't use external module
    --kerneldir=DIR        kernel build directory
(/lib/modules/2.6.22.5-31-bigsmp/build)
    --qemu-cc=""   compiler for qemu (needs gcc3.x) ()
    --disable-gcc-check    don't insist on gcc-3.x
                                   - this will break running without kvm


Host: openSUSE 10.3, 32-bit, Intel Core 2 CPU, KVM-45.

-Alexey Technologov

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&gro
up_id=180599

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[ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[SourceForge.net]

Bugs item #1807620, was opened at 2007-10-04 12:25
Message generated for change (Settings changed) made by aliguori
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: None
Group: None
Status: Open
>Resolution: Fixed
Priority: 2
Private: No
Submitted By: Technologov (technologov)
Assigned to: Nobody/Anonymous (nobody)
Summary: KVM's --disable-gcc-check doesn't work

Initial Comment:
KVM's configure switch: "--disable-gcc-check" doesn't work.

This bug makes KVM very hard to compile on openSUSE 10.2/10.3, which, unlike Fedora doesn't have compat-gcc-34 package.

Here is the error:

alexey@suse103-home:~/Linstall/kvm-45> ./configure --disable-gcc-check
./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc

According to HELP, it should work:
alexey@suse103-home:~/Linstall/kvm-45> ./configure --help
Usage: ./configure [options]

Options include:

    --prefix=PREFIX        where to install things (/usr/local)
    --with-patched-kernel  don't use external module
    --kerneldir=DIR        kernel build directory (/lib/modules/2.6.22.5-31-bigsmp/build)
    --qemu-cc=""   compiler for qemu (needs gcc3.x) ()
    --disable-gcc-check    don't insist on gcc-3.x
                                   - this will break running without kvm


Host: openSUSE 10.3, 32-bit, Intel Core 2 CPU, KVM-45.

-Alexey Technologov

----------------------------------------------------------------------

>Comment By: Anthony Liguori (aliguori)
Date: 2008-05-26 13:20

Message:
Logged In: YES 
user_id=120449
Originator: NO

I've confirmed that this has been fixed in the latest kvm-userspace git
tree.

----------------------------------------------------------------------

Comment By: Carlo Marcelo Arenas Belon (carenas)
Date: 2008-01-13 01:06

Message:
Logged In: YES 
user_id=36771
Originator: NO

$ tar -xvf /usr/portage/distfiles/kvm-47.tar.gz
$ cd kvm-47
$ ./configure --help | grep gcc
    --qemu-cc=CC           specify compiler for qemu (must be gcc-3.x)
    --disable-gcc-check    don't insist on gcc-3.x
$ gcc -v 2>&1 | grep "gcc version"
gcc version 4.1.2 (Gentoo 4.1.2 p1.0.1)
./configure --disable-gcc-check | grep gcc
C compiler        gcc
Host C compiler   gcc

can this be closed?

----------------------------------------------------------------------

Comment By: Technologov (technologov)
Date: 2007-11-08 02:54

Message:
Logged In: YES 
user_id=1839746
Originator: YES

This bug is not fixed yet. Reopened.

./configure --help

needs to give proper help.

----------------------------------------------------------------------

Comment By: Technologov (technologov)
Date: 2007-10-21 10:52

Message:
Logged In: YES 
user_id=1839746
Originator: YES

Itamar found a openSUSE 10.3-specific solution.

Itamar wrote:

This is a solution to the original problem with opensuse:

You can get gcc33 from the opensuse build service (this is the new
one-click-install)
http://software.opensuse.org/ymp/devel%3Atools%3Agcc/openSUSE_10.3/i586/
gcc33-3.3.3-41.6.i586.rpm.ymp

(or download specific rpm's from http://software.opensuse.org/search by
searching for gcc33).

-Itamar

----------------------------------------------------------------------

Comment By: Carlo Marcelo Arenas Belon (carenas)
Date: 2007-10-19 10:14

Message:
Logged In: YES 
user_id=36771
Originator: NO

Starting with kvm-47 all compiler detection is now being handled by QEMU
and works as explained in its documentation

----------------------------------------------------------------------

Comment By: Technologov (technologov)
Date: 2007-10-07 14:40

Message:
Logged In: YES 
user_id=1839746
Originator: YES

Tested and it works.

Well, the bug is still there. But it's not in KVM now. It's in
documentation.

Bug reopened. Documentation must match functionality.

-Alexey

----------------------------------------------------------------------

Comment By: Carlo Marcelo Arenas Belon (carenas)
Date: 2007-10-07 13:26

Message:
Logged In: YES 
user_id=36771
Originator: NO

running (or compiling) qemu with gcc4 is not supported and will result in
broken CPU emulation and crashes if kvm is not used (either because of
-no-kvm or the module not being loaded).  if you are ok with that then add
"--qemu-cc=gcc" as a workaround for this bug

----------------------------------------------------------------------

Comment By: Avi Kivity (avik)
Date: 2007-10-07 07:19

Message:
Logged In: YES 
user_id=539971
Originator: NO

Even if you specify --disable-gcc-check, you still need to choose a C
compiler.  Qemu won't choose gcc 4 by default.

Specify --qemu-cc in addition to --disable-gcc-check.

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599

[ kvm-Bugs-1807620 ] KVM's --disable-gcc-check doesn't work

[SourceForge.net]

Bugs item #1807620, was opened at 2007-10-04 21:55
Message generated for change (Settings changed) made by amitshah
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: None
Group: None
>Status: Closed
Resolution: Fixed
Priority: 2
Private: No
Submitted By: Technologov (technologov)
Assigned to: Nobody/Anonymous (nobody)
Summary: KVM's --disable-gcc-check doesn't work

Initial Comment:
KVM's configure switch: "--disable-gcc-check" doesn't work.

This bug makes KVM very hard to compile on openSUSE 10.2/10.3, which, unlike Fedora doesn't have compat-gcc-34 package.

Here is the error:

alexey@suse103-home:~/Linstall/kvm-45> ./configure --disable-gcc-check
./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc

According to HELP, it should work:
alexey@suse103-home:~/Linstall/kvm-45> ./configure --help
Usage: ./configure [options]

Options include:

    --prefix=PREFIX        where to install things (/usr/local)
    --with-patched-kernel  don't use external module
    --kerneldir=DIR        kernel build directory (/lib/modules/2.6.22.5-31-bigsmp/build)
    --qemu-cc=""   compiler for qemu (needs gcc3.x) ()
    --disable-gcc-check    don't insist on gcc-3.x
                                   - this will break running without kvm


Host: openSUSE 10.3, 32-bit, Intel Core 2 CPU, KVM-45.

-Alexey Technologov

----------------------------------------------------------------------

Comment By: Anthony Liguori (aliguori)
Date: 2008-05-26 22:50

Message:
Logged In: YES 
user_id=120449
Originator: NO

I've confirmed that this has been fixed in the latest kvm-userspace git
tree.

----------------------------------------------------------------------

Comment By: Carlo Marcelo Arenas Belon (carenas)
Date: 2008-01-13 11:36

Message:
Logged In: YES 
user_id=36771
Originator: NO

$ tar -xvf /usr/portage/distfiles/kvm-47.tar.gz
$ cd kvm-47
$ ./configure --help | grep gcc
    --qemu-cc=CC           specify compiler for qemu (must be gcc-3.x)
    --disable-gcc-check    don't insist on gcc-3.x
$ gcc -v 2>&1 | grep "gcc version"
gcc version 4.1.2 (Gentoo 4.1.2 p1.0.1)
./configure --disable-gcc-check | grep gcc
C compiler        gcc
Host C compiler   gcc

can this be closed?

----------------------------------------------------------------------

Comment By: Technologov (technologov)
Date: 2007-11-08 13:24

Message:
Logged In: YES 
user_id=1839746
Originator: YES

This bug is not fixed yet. Reopened.

./configure --help

needs to give proper help.

----------------------------------------------------------------------

Comment By: Technologov (technologov)
Date: 2007-10-21 20:22

Message:
Logged In: YES 
user_id=1839746
Originator: YES

Itamar found a openSUSE 10.3-specific solution.

Itamar wrote:

This is a solution to the original problem with opensuse:

You can get gcc33 from the opensuse build service (this is the new
one-click-install)
http://software.opensuse.org/ymp/devel%3Atools%3Agcc/openSUSE_10.3/i586/
gcc33-3.3.3-41.6.i586.rpm.ymp

(or download specific rpm's from http://software.opensuse.org/search by
searching for gcc33).

-Itamar

----------------------------------------------------------------------

Comment By: Carlo Marcelo Arenas Belon (carenas)
Date: 2007-10-19 19:44

Message:
Logged In: YES 
user_id=36771
Originator: NO

Starting with kvm-47 all compiler detection is now being handled by QEMU
and works as explained in its documentation

----------------------------------------------------------------------

Comment By: Technologov (technologov)
Date: 2007-10-08 00:10

Message:
Logged In: YES 
user_id=1839746
Originator: YES

Tested and it works.

Well, the bug is still there. But it's not in KVM now. It's in
documentation.

Bug reopened. Documentation must match functionality.

-Alexey

----------------------------------------------------------------------

Comment By: Carlo Marcelo Arenas Belon (carenas)
Date: 2007-10-07 22:56

Message:
Logged In: YES 
user_id=36771
Originator: NO

running (or compiling) qemu with gcc4 is not supported and will result in
broken CPU emulation and crashes if kvm is not used (either because of
-no-kvm or the module not being loaded).  if you are ok with that then add
"--qemu-cc=gcc" as a workaround for this bug

----------------------------------------------------------------------

Comment By: Avi Kivity (avik)
Date: 2007-10-07 16:49

Message:
Logged In: YES 
user_id=539971
Originator: NO

Even if you specify --disable-gcc-check, you still need to choose a C
compiler.  Qemu won't choose gcc 4 by default.

Specify --qemu-cc in addition to --disable-gcc-check.

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1807620&group_id=180599