Fix build of Windows cross-compiler (#20697, #22805)

Fix building of a Windows cross-compiler with Hadrian. First step towards #20697.

• Fixed on Linux (tested on ArchLinux)
• check that it also fixes cross-compilation from Darwin (first commit about AR; needs someone to check that it works): cf #22805 (closed)
• check that third commit makes sense for W32 (whatever that is) and doesn't break CI

added Windows backport needed:9.4 cross-compilation hadrian labels

mentioned in issue #20697

mentioned in issue #22805 (closed)

changed the description

RE: Cross compilation on Darwin

ar works, so this fixes #22805 (closed)

I was able to get much further than before, however, the build failed here:

...
| Run Ghc CompileHs (Stage0 InTreeLibs): utils/haddock/haddock-api/src/Haddock/Interface/Create.hs => _build/stage0/utils/haddock/build/Haddock/Interface/Create.o
| Run Ghc CompileHs (Stage0 InTreeLibs): utils/haddock/haddock-api/src/Haddock/Backends/Xhtml.hs => _build/stage0/utils/haddock/build/Haddock/Backends/Xhtml.o
| Run Ghc CompileHs (Stage0 InTreeLibs): utils/haddock/haddock-api/src/Haddock/Interface.hs => _build/stage0/utils/haddock/build/Haddock/Interface.o
| Executable found: x86_64-w64-mingw32-ld => /opt/homebrew/bin/x86_64-w64-mingw32-ld
| Package 'rts' configuration flags: configure --distdir /Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/_build/stage1/rts --disable-executable-stripping --disable-library-stripping --disable-executable-stripping --disable-library-stripping --cabal-file rts/rts.cabal --ipid $pkg-$version --prefix ${pkgroot}/.. --htmldir ${pkgroot}/../../doc/html/libraries/rts-1.0.2 --with-ghc=/Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/_build/stage0/bin/x86_64-w64-mingw32-ghc --with-ghc-pkg=/Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/_build/stage0/bin/x86_64-w64-mingw32-ghc-pkg --with-gcc=/opt/homebrew/bin/x86_64-w64-mingw32-gcc --with-ar=/opt/homebrew/bin/x86_64-w64-mingw32-ar --ghc-option=-no-global-package-db --ghc-option=-package-db=/Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/_build/stage1/inplace/package.conf.d --ghc-pkg-option=--global-package-db=/Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/_build/stage1/inplace/package.conf.d --enable-library-vanilla --enable-library-profiling --disable-library-for-ghci --disable-shared --with-ld=x86_64-w64-mingw32-ld --with-alex=/Users/romes/.cabal/bin/alex --with-happy=/Users/romes/.cabal/bin/happy --configure-option=CFLAGS=-iquote /Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/rts --gcc-options=-iquote /Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/rts --configure-option=--host=x86_64-w64-mingw32 --configure-option=--with-cc=/opt/homebrew/bin/x86_64-w64-mingw32-gcc --ghc-option=-ghcversion-file=rts/include/ghcversion.h --ghc-option=-ghcversion-file=rts/include/ghcversion.h --flags=profiling debug -dynamic threaded -use-system-libffi -libffi-adjustors -find-ptr -v0
# cabal-configure (for _build/stage1/rts/setup-config)
configure: WARNING: unrecognized options: --with-compiler, --with-cc
checking build system type... aarch64-apple-darwin22.1.0
checking host system type... x86_64-pc-windows
Unknown OS windows
Error when running Shake build system:
  at action, called at src/Rules.hs:38:19 in main:Rules
  at need, called at src/Rules.hs:60:5 in main:Rules
* Depends on: _build/stage1/lib/package.conf.d/rts-1.0.2.conf
  at apply1, called at src/Development/Shake/Internal/Rules/Oracle.hs:159:32 in shk-0.19.7-51192a6a:Development.Shake.Internal.Rules.Oracle
* Depends on: OracleQ (ContextDataKey (Context {stage = Stage1, package = Package {pkgType = Library, pkgName = "rts", pkgPath = "rts"}, way = v, iplace = Final}))
  at need, called at src/Hadrian/Oracles/Cabal/Rules.hs:54:9 in main:Hadrian.Oracles.Cabal.Rules
* Depends on: _build/stage1/rts/setup-config
* Raised the exception:
ExitFailure 1

Seems to be the first step regarding stage1 (configure --distdir /Users/romes/ghc-dev/x86_64-w64-mingw32-ghc/_build/stage1/rts)

Could you try:

diff --git m4/fptools_set_haskell_platform_vars.m4 m4/fptools_set_haskell_platform_vars.m4
index 1a32b3046b..02b5b4e53c 100644
--- m4/fptools_set_haskell_platform_vars.m4
+++ m4/fptools_set_haskell_platform_vars.m4
@@ -82,7 +82,7 @@ AC_DEFUN([FPTOOLS_SET_HASKELL_PLATFORM_VARS_SHELL_FUNCTIONS],
         solaris2)
             test -z "[$]2" || eval "[$]2=OSSolaris2"
             ;;
-        mingw32)
+        mingw32|windows)
             test -z "[$]2" || eval "[$]2=OSMinGW32"
             ;;
         freebsd)
diff --git m4/ghc_convert_os.m4 m4/ghc_convert_os.m4
index 8e2825d940..d4aa639cd5 100644
--- m4/ghc_convert_os.m4
+++ m4/ghc_convert_os.m4
@@ -22,6 +22,9 @@ AC_DEFUN([GHC_CONVERT_OS],[
       openbsd*)
         $3="openbsd"
         ;;
+      windows)
+        $3="mingw32"
+        ;;
       # As far as I'm aware, none of these have relevant variants
       freebsd|dragonfly|hpux|linuxaout|kfreebsdgnu|freebsd2|mingw32|darwin|nextstep2|nextstep3|sunos4|ultrix|haiku)
         $3="$1"

With that patch I'm making further progress on stage1. I'll let you know if it succeeds

@hsyl20 this patch should be a commit

I've successfully cross-compiled GHC on this (rebased) branch + that patch (on host aarch64-apple-darwin to target x86_64-w64-mingw32)

Let's try to get this merged!

Done!

Very good work both!

added 403 commits

• 58fa3f5f...14b5982a - 399 commits from branch ghc:master
• 77be26da - Hadrian: correctly detect AR at-file support
• be4a2ac7 - Hadrian: fix Windows cross-compilation
• bdfb4973 - Fix RTS build on Windows
• a6018e00 - configure: support "windows" as an OS

Compare with previous version

marked the checklist item check that it also fixes cross-compilation from Darwin (first commit about AR; needs someone to check that it works): cf #22805 (closed) as completed

marked this merge request as ready

changed title from Fix build of Windows cross-compiler (#20697) to Fix build of Windows cross-compiler (#20697, #22805)

added backport needed:9.6 label

marked the checklist item check that third commit makes sense for W32 (whatever that is) and doesn't break CI as completed

requested review from @bgamari

added 28 commits

• a6018e00...1c050ed2 - 24 commits from branch ghc:master
• ba4a741c - Hadrian: correctly detect AR at-file support
• 546ea6b7 - Hadrian: fix Windows cross-compilation
• 3d6df963 - Fix RTS build on Windows
• 4568afa8 - configure: support "windows" as an OS

Compare with previous version

approved this merge request

assigned to @marge-bot

I will attempt to batch this MR (!9808 (closed))...

Merged in 2fdf22ae

closed

mentioned in merge request !9829 (closed)