help compilation qemu

help compilation qemu

[Juan carlos Rebate]

Good morning, in a previous post I was debating with some nice users (for
technical reasons I can't retrieve that thread)The point is that although
the qemu wiki says it can't compile with cygwin for 64-bit it actually can,
and for technical reasons I haven't been able to communicate it before,The
case is that making a couple of adjustments when looking for all the mingw
packages if they can be found, but there is a problem,Well, really two
problems.1 the compiler is extremely slow, gcc on Linux is about 10 times
faster, How could I speed up the compilation process?.
2 the executables produced are too fat, for example qemu-system-i386 is 65
MB, but it should be 10.5 MB, if I use the -s option in configure returns
an unknown error message, how could I fix it? Thank you

Re: help compilation qemu

[Csaba Ráduly]

Hi Juan Carlos,

On 24/05/2020 02:08, Juan carlos Rebate via Cygwin wrote:
...

> 1 the compiler is extremely slow, gcc on Linux is about 10 times
> faster, How could I speed up the compilation process?.

Unfortunately, Cygwin's emulation of fork() is slow compared to the native Linux 
implementation (I've seen 1000x difference once, in a test launching the same 
program repeatedly). There's not much you can do about it, except getting faster 
hardware. A C++ build involves lots and lots of programs being forked.

> 2 the executables produced are too fat, for example qemu-system-i386 is 65
> MB, but it should be 10.5 MB, if I use the -s option in configure returns
> an unknown error message, how could I fix it? Thank you

Why do you think qemu-system-i386 "should be 10.5 MB" ?
Are you using 32-bit or 64-bit Cygwin? 64-bit executables are usually bigger 
than their 32-bit counterparts (although rarely six times as big).

You really need to give us more information if you hope to get help, like the 
actual commands you used and the exact error message.

Without those, we can only guess, and my crystal ball is not very reliable.

If you want to strip the resulting executables, you could try setting the 
LDFLAGS environment variable to '-s' before running configure

Csaba
-- 
You can get very substantial performance improvements
by not doing the right thing. - Scott Meyers, An Effective C++11/14 Sampler
So if you're looking for a completely portable, 100% standards-conformat way
to get the wrong information: this is what you want. - Scott Meyers (C++TDaWYK)

Re: help compilation qemu

[Juan carlos Rebate]

Hi Caba, I know qemu-system-i386 because the official binary is that
size.As for the command used I use this:x86_64-w64-mingw32- this way it
compiles perfectly except for the file sizes, if I add the option - s the
error Bash option -s unknown, I use 64-bit

El dom., 24 may. 2020 11:32, Csaba Ráduly via Cygwin <cygwin@cygwin.com>
escribió:

>
> Hi Juan Carlos,
>
> On 24/05/2020 02:08, Juan carlos Rebate via Cygwin wrote:
> ...
>
> > 1 the compiler is extremely slow, gcc on Linux is about 10 times
> > faster, How could I speed up the compilation process?.
>
> Unfortunately, Cygwin's emulation of fork() is slow compared to the native
> Linux
> implementation (I've seen 1000x difference once, in a test launching the
> same
> program repeatedly). There's not much you can do about it, except getting
> faster
> hardware. A C++ build involves lots and lots of programs being forked.
>
> > 2 the executables produced are too fat, for example qemu-system-i386 is
> 65
> > MB, but it should be 10.5 MB, if I use the -s option in configure returns
> > an unknown error message, how could I fix it? Thank you
>
> Why do you think qemu-system-i386 "should be 10.5 MB" ?
> Are you using 32-bit or 64-bit Cygwin? 64-bit executables are usually
> bigger
> than their 32-bit counterparts (although rarely six times as big).
>
> You really need to give us more information if you hope to get help, like
> the
> actual commands you used and the exact error message.
>
> Without those, we can only guess, and my crystal ball is not very reliable.
>
> If you want to strip the resulting executables, you could try setting the
> LDFLAGS environment variable to '-s' before running configure
>
> Csaba
> --
> You can get very substantial performance improvements
> by not doing the right thing. - Scott Meyers, An Effective C++11/14 Sampler
> So if you're looking for a completely portable, 100% standards-conformat
> way
> to get the wrong information: this is what you want. - Scott Meyers
> (C++TDaWYK)
> --
> Problem reports:      https://cygwin.com/problems.html
> FAQ:                  https://cygwin.com/faq/
> Documentation:        https://cygwin.com/docs.html
> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
>

Re: help compilation qemu

[Eliot Moss]

Dear Juan Carlos: I think by "command" we mean the full command line, plus information about the 
version of the compiler, etc.

Regards - Eliot Moss

Re: help compilation qemu

[Hans-Bernhard Bröker]

Am 24.05.2020 um 17:30 schrieb Juan carlos Rebate via Cygwin:

[Can you _please_ cut down on the TOFU? Thanks ]

> Hi Caba, I know qemu-system-i386 because the official binary is that
                               ^^^^\

> size.As for the command used I use this:x86_64-w64-mingw32- this way it
                                           ^^^^^^

Those two marked details form a mismatch.  If it's the i386 version 
you're trying to build, then the tool chain (equivalent to the --target 
argument in configure) is i686-w64-mingw32.

> compiles perfectly except for the file sizes, if I add the option - s 

Add it where?

help compilation qemu

[Juan carlos Rebate]

Hello, it is the first time that I write here, sorry for the possible
malfunctions of the mailing list.I am interested in compiling qemu with
cygwin and the documentation is scarce, it only indicates that the
environment is complete but it does not indicate all the necessary
components,The components that they mention are not available in cygwin,
for example Mingw64-686-pkconfig is not included in the repositories, could
someone give me a complete manual? Thank you very much in advance

Re: help compilation qemu

[john doe]

On 5/2/2020 9:28 PM, Juan carlos Rebate via Cygwin wrote:
> Hello, it is the first time that I write here, sorry for the possible
> malfunctions of the mailing list.I am interested in compiling qemu with
> cygwin and the documentation is scarce, it only indicates that the
> environment is complete but it does not indicate all the necessary
> components,The components that they mention are not available in cygwin,
> for example Mingw64-686-pkconfig is not included in the repositories, could
> someone give me a complete manual? Thank you very much in advance
> --

FYI, qemu for Windows is available.

--
John Doe

Re: help compilation qemu

[Juan carlos Rebate]

I'm already aware of the availability of binaries for windows, but I want
to compile it myself, I ask because qemu documentation is sparse.

El sáb., 2 may. 2020 21:39, john doe <johndoe65534@mail.com> escribió:

> On 5/2/2020 9:28 PM, Juan carlos Rebate via Cygwin wrote:
> > Hello, it is the first time that I write here, sorry for the possible
> > malfunctions of the mailing list.I am interested in compiling qemu with
> > cygwin and the documentation is scarce, it only indicates that the
> > environment is complete but it does not indicate all the necessary
> > components,The components that they mention are not available in cygwin,
> > for example Mingw64-686-pkconfig is not included in the repositories,
> could
> > someone give me a complete manual? Thank you very much in advance
> > --
>
> FYI, qemu for Windows is available.
>
> --
> John Doe
> --
> Problem reports:      https://cygwin.com/problems.html
> FAQ:                  https://cygwin.com/faq/
> Documentation:        https://cygwin.com/docs.html
> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
>

Re: help compilation qemu

[Maarten Hoes]

Hi,

I have no personal experience with this, but when I take a look at the QEMU
wiki, it seems that :


[1]
Builds with cygwin are not really supported.
https://wiki.qemu.org/Hosts/W32#Native_builds_with_Cygwin


[2]
A supported way of building QEMU on Windows is with MSYS2
https://wiki.qemu.org/Hosts/W32#Native_builds_with_MSYS2


Hope this helps.


- Maarten


On Sat, May 2, 2020 at 9:31 PM Juan carlos Rebate via Cygwin <
cygwin@cygwin.com> wrote:

> Hello, it is the first time that I write here, sorry for the possible
> malfunctions of the mailing list.I am interested in compiling qemu with
> cygwin and the documentation is scarce, it only indicates that the
> environment is complete but it does not indicate all the necessary
> components,The components that they mention are not available in cygwin,
> for example Mingw64-686-pkconfig is not included in the repositories, could
> someone give me a complete manual? Thank you very much in advance
> --
> Problem reports:      https://cygwin.com/problems.html
> FAQ:                  https://cygwin.com/faq/
> Documentation:        https://cygwin.com/docs.html
> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
>

Re: help compilation qemu

[Juan carlos Rebate]

I can't use msys2 because when I use the Syu command it is not able to
resolve the download url,The only missing component is
mingw64-686-pkconfig, all other components if they are in cygwin

El sáb., 2 may. 2020 22:24, Maarten Hoes <hoes.maarten@gmail.com> escribió:

> Hi,
>
> I have no personal experience with this, but when I take a look at the
> QEMU wiki, it seems that :
>
>
> [1]
> Builds with cygwin are not really supported.
> https://wiki.qemu.org/Hosts/W32#Native_builds_with_Cygwin
>
>
> [2]
> A supported way of building QEMU on Windows is with MSYS2
> https://wiki.qemu.org/Hosts/W32#Native_builds_with_MSYS2
>
>
> Hope this helps.
>
>
> - Maarten
>
>
> On Sat, May 2, 2020 at 9:31 PM Juan carlos Rebate via Cygwin <
> cygwin@cygwin.com> wrote:
>
>> Hello, it is the first time that I write here, sorry for the possible
>> malfunctions of the mailing list.I am interested in compiling qemu with
>> cygwin and the documentation is scarce, it only indicates that the
>> environment is complete but it does not indicate all the necessary
>> components,The components that they mention are not available in cygwin,
>> for example Mingw64-686-pkconfig is not included in the repositories,
>> could
>> someone give me a complete manual? Thank you very much in advance
>> --
>> Problem reports:      https://cygwin.com/problems.html
>> FAQ:                  https://cygwin.com/faq/
>> Documentation:        https://cygwin.com/docs.html
>> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
>>
>

Re: help compilation qemu

[Juan carlos Rebate]

Yes, pkconfig is among the requirements although today in 2020 that package
is not in cygwin, due to the scarce documentation in this regard, I will
try to see if a cross-compilation is feasible.

El sáb., 2 may. 2020 23:47, Vanda Vodkamilkevich <
vanda.vodkamilkevich@gmail.com> escribió:

> Le sam. 2 mai 2020 à 22:46, Juan carlos Rebate via Cygwin <
> cygwin@cygwin.com> a écrit :
>
>> I can't use msys2 because when I use the Syu command it is not able to
>> resolve the download url,The only missing component is
>> mingw64-686-pkconfig, all other components if they are in cygwin
>>
>> El sáb., 2 may. 2020 22:24, Maarten Hoes <hoes.maarten@gmail.com>
>> escribió:
>>
>> > Hi,
>> >
>> > I have no personal experience with this, but when I take a look at the
>> > QEMU wiki, it seems that :
>> >
>> >
>> > [1]
>> > Builds with cygwin are not really supported.
>> > https://wiki.qemu.org/Hosts/W32#Native_builds_with_Cygwin
>> >
>> >
>> > [2]
>> > A supported way of building QEMU on Windows is with MSYS2
>> > https://wiki.qemu.org/Hosts/W32#Native_builds_with_MSYS2
>> >
>> >
>> > Hope this helps.
>> >
>> >
>> > - Maarten
>> >
>> >
>> > On Sat, May 2, 2020 at 9:31 PM Juan carlos Rebate via Cygwin <
>> > cygwin@cygwin.com> wrote:
>> >
>> >> Hello, it is the first time that I write here, sorry for the possible
>> >> malfunctions of the mailing list.I am interested in compiling qemu with
>> >> cygwin and the documentation is scarce, it only indicates that the
>> >> environment is complete but it does not indicate all the necessary
>> >> components,The components that they mention are not available in
>> cygwin,
>> >> for example Mingw64-686-pkconfig is not included in the repositories,
>> >> could
>> >> someone give me a complete manual? Thank you very much in advance
>> >> --
>> >> Problem reports:      https://cygwin.com/problems.html
>> >> FAQ:                  https://cygwin.com/faq/
>> >> Documentation:        https://cygwin.com/docs.html
>> >> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
>> >>
>> >
>> --
>> Problem reports:      https://cygwin.com/problems.html
>> FAQ:                  https://cygwin.com/faq/
>> Documentation:        https://cygwin.com/docs.html
>> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
>
>
> Hi,
>
> In the past I succeeded in compiling Qemu with cygwin. Last update of the
> page http://lassauge.free.fr/qemu/) for this is a bit old (2016! ) but I
> could dig in my backup flash drive to find the real last time if needed...
>
> In the list of dependencies there was in fact  Mingw64-686-pkconfig (which
> should indicate that the package was existing at time).
>
> Sadly the PC containing the development environment I used for Qemu is at
> my work place and not available actually (up to May 11th) due to the
> lockdown :(
>
> Eric.
>

Re: help compilation qemu

[Maarten Hoes]

Hrm.

That's odd. I just installed MSYS2 and followed the instructions provided
in the QEMU wiki for MSYS2, and all preparatory steps of running
msys2/pacman/git/configure (only excluding the actual 'make' for
compilation) work as expected. There must be a difference between our
setups/steps/configurations if that doesn't work for you.


- Maarten


On Sat, May 2, 2020 at 10:44 PM Juan carlos Rebate via Cygwin <
cygwin@cygwin.com> wrote:

> I can't use msys2 because when I use the Syu command it is not able to
> resolve the download url,The only missing component is
> mingw64-686-pkconfig, all other components if they are in cygwin
>
> El sáb., 2 may. 2020 22:24, Maarten Hoes <hoes.maarten@gmail.com>
> escribió:
>
> > Hi,
> >
> > I have no personal experience with this, but when I take a look at the
> > QEMU wiki, it seems that :
> >
> >
> > [1]
> > Builds with cygwin are not really supported.
> > https://wiki.qemu.org/Hosts/W32#Native_builds_with_Cygwin
> >
> >
> > [2]
> > A supported way of building QEMU on Windows is with MSYS2
> > https://wiki.qemu.org/Hosts/W32#Native_builds_with_MSYS2
> >
> >
> > Hope this helps.
> >
> >
> > - Maarten
> >
> >
> > On Sat, May 2, 2020 at 9:31 PM Juan carlos Rebate via Cygwin <
> > cygwin@cygwin.com> wrote:
> >
> >> Hello, it is the first time that I write here, sorry for the possible
> >> malfunctions of the mailing list.I am interested in compiling qemu with
> >> cygwin and the documentation is scarce, it only indicates that the
> >> environment is complete but it does not indicate all the necessary
> >> components,The components that they mention are not available in cygwin,
> >> for example Mingw64-686-pkconfig is not included in the repositories,
> >> could
> >> someone give me a complete manual? Thank you very much in advance
> >> --
> >> Problem reports:      https://cygwin.com/problems.html
> >> FAQ:                  https://cygwin.com/faq/
> >> Documentation:        https://cygwin.com/docs.html
> >> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
> >>
> >
> --
> Problem reports:      https://cygwin.com/problems.html
> FAQ:                  https://cygwin.com/faq/
> Documentation:        https://cygwin.com/docs.html
> Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple
>

Re: help compilation qemu

[Eliot Moss]

On 5/3/2020 8:52 AM, Maarten Hoes via Cygwin wrote:
> Hrm.
> 
> That's odd. I just installed MSYS2 and followed the instructions provided
> in the QEMU wiki for MSYS2, and all preparatory steps of running
> msys2/pacman/git/configure (only excluding the actual 'make' for
> compilation) work as expected. There must be a difference between our
> setups/steps/configurations if that doesn't work for you.

I can imagine issues with both MSYS and Cygwin installed, if the order
of things on paths is not right, e.g., getting the Cygwin version of
something when trying to run MSYS, or vice versa.

Maybe try to make sure, when building qemu under MSYS, that no Cygwin
things are in your path?

Best wishes -- Eliot

Re: help compilation qemu

[Maarten Hoes]

Hi,

On Sun, May 3, 2020 at 4:54 PM Eliot Moss <moss@cs.umass.edu> wrote:

> On 5/3/2020 8:52 AM, Maarten Hoes via Cygwin wrote:
> > Hrm.
> >
> > That's odd. I just installed MSYS2 and followed the instructions provided
> > in the QEMU wiki for MSYS2, and all preparatory steps of running
> > msys2/pacman/git/configure (only excluding the actual 'make' for
> > compilation) work as expected. There must be a difference between our
> > setups/steps/configurations if that doesn't work for you.
>
> I can imagine issues with both MSYS and Cygwin installed, if the order
> of things on paths is not right, e.g., getting the Cygwin version of
> something when trying to run MSYS, or vice versa.
>
> Maybe try to make sure, when building qemu under MSYS, that no Cygwin
> things are in your path?
>
> Best wishes -- Eliot
>


Good point. I tried to verify that, so I did


[1a]
On a cygwin prompt
echo $PATH | grep -i msys

[1b]
On a msys prompt
echo $PATH | grep -i cyg


And got no conflicting results. (msys is not in the cygwin path, and cygwin
is not in the msys path).


[2]
'mount' only showed cygdrive on a cygwin prompt, and only msys on a msys
prompt


[3]
Looked for a 'msys' string in a random binary in the path:

[3a]
On a msys prompt:
strings `which ls.exe` | grep -i msys

gave me msys hits.


[3b]
on a cygwin prompt:
strings `which ls.exe` | grep -i msys

gave me no hits.



So it at least appears to me that the environments are not conflicting for
me personally. Of course, that could very well be the case for the error
results of the original poster.

PS:
if anyone knows of better tests/checks to see if the environments are
intermingled in some way, I'd love to hear it.



- Maarten