Re: [Qemu-devel] -icount changes physical address assignments in QEMU 2.10/2.11

[alarson]

"Peter Maydell" <address@hidden> wrote on 04/06/2018 04:41:01 
AM:

> From: "Peter Maydell" <address@hidden>
> To: address@hidden
> Cc: "QEMU Developers" <address@hidden>, "Stefan Weil" 
<address@hidden>
> Date: 04/06/2018 04:41 AM
> Subject: Re: [Qemu-devel] -icount changes physical address assignments 
in QEMU 2.10/2.11
> 
> On 5 April 2018 at 22:23,  <address@hidden> wrote:
> > "Peter Maydell" <address@hidden> wrote on 04/05/2018 
12:28:01
> > PM:
> >
> >> From: "Peter Maydell" <address@hidden>
> >> To: address@hidden
> >> Cc: "QEMU Developers" <address@hidden>
> >> Date: 04/05/2018 12:28 PM
> >> Subject: Re: [Qemu-devel] -icount changes physical address 
assignments
> > in QEMU 2.10/2.11
> >>
> >> On 5 April 2018 at 17:44,  <address@hidden> wrote:
> >> > "Peter Maydell" <address@hidden> wrote on 04/05/2018
> > 09:05:53
> >> > AM:
> >> >> I've just tried your attached test image ...
> >> >
> >> > Curious.  I just downloaded qemu-2.12.0-rc2.tar.xz and built it 
using
> >> > Cygwin (a version from about a month ago) using mingw compilers
> >> > (mingw64-i686-gcc-g++ 6.4.0), and I still see the issue when the
> >> > resulting QEMU binary is run using -icount 2 against my test 
binary,
> >> > but not when run without -icount.  Here are the commands used:
> >> >
> >> > ../qemu-2.12.0-rc2/configure --python=/usr/bin/python \
> >> >    '--with-pkgversion=DDCI QEMU 2.12.0-rc2' \
> >> >    --prefix=/usr/local/qemu \
> >> >    --enable-sdl --with-sdlabi=2.0 \
> >> >    '--target-list=aarch64-softmmu ppc64-softmmu x86_64-softmmu' \
> >> >    --cross-prefix=i686-w64-mingw32-
> >> > /usr/bin/make -Otarget -j 8
> >> >
> >> > Any suggestions of things to try?
> >>
> >> Can you reproduce the problem on a Linux host? It would
> >> be interesting to identify if this is a Windows-host
> >> specific issue somehow.
> >
> > Linux "works".  I installed ubuntu 17.10 in a VM on my windows box,
> > recompiled QEMU 2.12.0-rc2 (same sources as above), using a configure
> > line the same as above except omitting --cross-prefix and 
--with-sdlabi.
> > Both with "-icount 2" and without show expected results.
> >
> > I installed a fresh Cygwin with just the packages suggested at
> > https://wiki.qemu.org/Hosts/W32#Native_builds_with_Mingw-w64 (plus
> > some obviously missing ones like python, make, etc.) and the problem
> > persists.  The updated configure line is:
> >
> > ../qemu-2.12.0-rc2/configure \
> >     '--with-pkgversion=DDCI QEMU 2.12.0-rc2' \
> >     --prefix=/usr/local/qemu \
> >     '--target-list=aarch64-softmmu ppc64-softmmu x86_64-softmmu' \
> >     --cross-prefix=i686-w64-mingw32-
> 
> Hmm, if it's Windows-only that's unfortunate, since I'm not really
> in a position to debug things that only happon on Windows hosts.
> 
> Stefan, does this sort of bug sound familiar at all?
> 
> Looking at your --cross-prefix you seem to be building 32-bit
> binaries; was your Ubuntu VM 32 bit or 64 bit? I'm wondering
> if this might turn out to be a 32-bit host issue rather than
> necessarily a Windows one.

1. Ubuntu 17.10 is 64-bit, compilation was native, run on the
   compilation host.  I.e., I did not cross compile to windows.
2. Cygwin was a 64-bit install, 64-bit windows 7 host.  I followed the
   instructions on the wiki.  I was curious about the "ming32" part
   myself, but cygwin package search doesn't indicate an obvious (to
   me) replacement.

I was not successful with the wiki instructions for "Native builds
with MSYS2":

  ./qemu-2.12.0-rc2/configure --python=/usr/bin/python2 \
      '--with-pkgversion=DDCI QEMU 2.12.0-rc2' \
      --prefix=/usr/local/qemu \
      '--target-list=aarch64-softmmu ppc64-softmmu x86_64-softmmu'
  make
  ...
  C:\msys2-x86_64_20161025\msys64\mingw64\bin\ar.exe: creating 
libfdt/libfdt.a
  make[1]: *** No rule to make target ...build/capstone/capstone.lib'. 
Stop.
  make: *** [Makefile:503: subdir-capstone] Error 2