Re: [PATCH] Replace CONFIG_WIN32 with CONFIG_WIN64

["Daniel P. Berrangé" <berrange@redhat.com>]

On Thu, Jan 22, 2026 at 10:03:52AM +0100, Thomas Huth wrote:
> From: Thomas Huth <thuth@redhat.com>
> 
> We stopped supported 32-bit Windows hosts a while ago already, so
> let's rename CONFIG_WIN32 to CONFIG_WIN64 now to make it clear
> that this switch is not about 32-bit Windows anymore.
> 
> The patch has been created with a simple sed statement:
> 
>  sed -i s/CONFIG_WIN32/CONFIG_WIN64/g $(grep -rl CONFIG_WIN32 *)
> 
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>  meson.build           |  2 +-
>  qapi/char.json        |  4 +--
>  qapi/misc.json        |  2 +-
>  qga/qapi-schema.json  | 76 +++++++++++++++++++++----------------------
>  include/qemu/futex.h  |  2 +-
>  include/qemu/xattr.h  |  2 +-
>  hw/usb/host-libusb.c  | 18 +++++-----
>  io/channel-watch.c    | 10 +++---
>  ui/gtk.c              |  2 +-
>  util/cacheflush.c     |  4 +--
>  util/sys_membarrier.c |  2 +-
>  scripts/checkpatch.pl |  2 +-
>  12 files changed, 63 insertions(+), 63 deletions(-)
> 
> diff --git a/meson.build b/meson.build
> index a84f14258b0..01b9a5c22ce 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -2422,7 +2422,7 @@ config_host_data.set('CONFIG_GCOV', get_option('b_coverage'))
>  config_host_data.set('CONFIG_LIBUDEV', libudev.found())
>  config_host_data.set('CONFIG_LINUX', host_os == 'linux')
>  config_host_data.set('CONFIG_POSIX', host_os != 'windows')
> -config_host_data.set('CONFIG_WIN32', host_os == 'windows')
> +config_host_data.set('CONFIG_WIN64', host_os == 'windows')

While relevant to qapi file conditions, from a C code pov all of these
are redundant as the compiler has all these facts built-in

  #ifdef CONFIG_LINUX =>    #ifdef __linux__
  #ifdef CONFIG_POSIX =>    #if !defined(_WIN32) 
  #ifdef CONFIG_WIN32 =>    #ifdef _WIN32

NB,  _WIN32 *is* set on 64-bit Windows platforms too, so using
_WIN64 is only needed if you have a code path that is exclusively
64-bit only, so there's little need for us to use _WIN64.

And of course we are horribly inconsistent in what we use:

$ git grep -E '#if.*_WIN32' | wc -l
284

$ git grep -E '#if.*__linux__' | wc -l
90

$ git grep -E '#if.*CONFIG_LINUX' | wc -l
142
$ git grep -E '#if.*CONFIG_WIN' | wc -l
16

I'm inclined to posion all these from the C source though, and only
these them from non-C locations.

Also IMHO  CONFIG_WIN  or CONFIG_WINDOWS is preferrable - we don't
add '32' or '64' suffixes to CONFIG_LINUX or CONFIG_POSIX, so I don't
see a reason to keep doing it for Windows.

With regards,
Daniel
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