[U-Boot] Using MinGW gcc cross-compiling host tools for Windows broken

[Peter Tyser]

Hi Bin,

----- Original Message -----
> From: "Bin Meng" <bmeng.cn at gmail.com>
> To: "ptyser" <ptyser at xes-inc.com>, "Vladimir Yakovlev" <nagos at inbox.ru>, "Mike Frysinger" <vapier at gentoo.org>, "Remy
> Bohmer" <linux at bohmer.net>, "U-Boot Mailing List" <u-boot at lists.denx.de>
> Cc: "Tom Rini" <trini at konsulko.com>
> Sent: Monday, October 14, 2019 4:46:16 AM
> Subject: Using MinGW gcc cross-compiling host tools for Windows broken

> Hi Peter,
> 
> I noticed that you were the first one that added support to build
> native Win32 tools using MinGW GCC via:
> 
> commit 2f8d396b9302eddcd8d552648e101a46b7a80acd
> Author: Peter Tyser <ptyser at xes-inc.com>
> Date:   Fri Mar 13 18:54:51 2009 -0500
> 
>    Add support for building native win32 tools
> 
>    Add support for compiling the host tools in the tools directory using
>    the MinGW toolchain.  This produces executables which can be used on
>    standard Windows computers without requiring cygwin.
> 
>    One must specify the MinGW compiler and strip utilities as if they
>    were the host toolchain in order to build win32 executables, eg:
> 
>    make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
> 
>    Signed-off-by: Peter Tyser <ptyser at xes-inc.com>
> 
> There are also several follow-up commits that fixed the build errors
> from time to time:
> 
> commit 8b6a4952e6064dc558cb7d5d375990b17491f26f
> Author: Vladimir Yakovlev <nagos at inbox.ru>
> Date:   Sat Jul 7 10:05:06 2012 +0000
> 
>    tools: Fix mingw tools build
> 
>    mkenvimage does not build due to missed os_support.o and unsupported
>    file modes S_IRGRP S_IWGRP.
>    Tested with mingw 4.2.1 on ubuntu 12.04.
> 
>    Signed-off-by: Vladimir Yakovlev <nagos at inbox.ru>
> 
> commit b050c72d52c4e30d5b978ab6758f8dcdbe5c690c
> Author: Mike Frysinger <vapier at gentoo.org>
> Date:   Tue Apr 20 05:49:30 2010 -0400
> 
>    compiler.h: add uint typedef
> 
>    Recent crc changes started using the "uint" type in headers that are used
>    on the build system.  This subsequently broke mingw targets as they do not
>    provide such a type.  So add this basic typedef to compiler.h so that we
>    do not have to worry about this breaking again in the future.
> 
>    Signed-off-by: Mike Frysinger <vapier at gentoo.org>
> 
> commit faf36c1437c95e4a86835633d9801c5f6396a3c7
> Author: Remy Bohmer <linux at bohmer.net>
> Date:   Wed Oct 28 22:13:36 2009 +0100
> 
>    Fix mingw tools build
> 
>    mkimage does not build due to missing strtok_r() and getline()
> implementation
> 
>    Signed-off-by: Remy Bohmer <linux at bohmer.net>
> 
> Today I tried to build the Windows tools by following the README, and
> got build errors.
> 
> $ make HOSTCC=/usr/bin/x86_64-w64-mingw32-gcc tools
> 
> note: I am running this from Linux. It's not clear to me whether we
> should run this from Windows natively or cross-compile on Linux.

It was intended to be cross-compiled on a Linux box.

> It seems that this MinGW Windows build has been broken for quite a long time.
> 
> Will you address this? Thanks!

I had a quick look at getting compilation working, and my vote is to remove
support for the MinGW compilation.
- It can't be too popular since the compilation issues haven't been
flagged for a long time.

- The motivation 10 years ago was to support customers that used Windows as
their OS development environment, mostly for VxWorks.  Development under a
100% Windows environment seems a lot less common nowadays.  Virtual machines
and Windows Subsystem for Linux also make it much easier to run Linux apps
in a Windows development environment.  My company hasn't been distributing
the MinGW binary for a number of years now as a data point.

- The feature set of some of the U-Boot tools has increased quite a bit
which makes it non-trivial to support with MinGW.  For example mkimage links
with libssl and libcrypto.

I'm guessing more duct tape on the make system would be needed to get
MinGW working, and my thought is that ugliness isn't worth the benefit
anymore.

I'm happy to gin up a patch if others agree and think removing
MinGW support makes sense.

Regards,
Peter