Running “C:\msys64\msys2_shell.cmd -mingw64 -mintty" has the same effect as clicking on the "MinGW-w64 Win64 Shell" shortcut. It is the proper way to start an mingw64 shell. Interesting. Most shells are started by ‘make’. I think it uses the SHELL envt variable to decide what to start. Currently I have that set to * c:/msys64/usr/bin/bash Are you saying that I should put * C:\msys64\msys2_shell.cmd -mingw64 -mintty into my SHELL envt variable? (Also: I always a shell within emacs, rather that an msys window, and it uses SHELL to decide what to run.) Also: is this related to the export MSYSTEM=MINGW64 question? Thanks Simon From: ghc-devs <ghc-devs-bounces@haskell.org> On Behalf Of Shao, Cheng Sent: 26 March 2018 11:07 To: ghc-devs@haskell.org Subject: Re: Windows Hi Simon, Running “C:\msys64\msys2_shell.cmd -mingw64 -mintty" has the same effect as clicking on the "MinGW-w64 Win64 Shell" shortcut. It is the proper way to start an mingw64 shell. If you have run "pacman -S" to update the MSYS2 packages before, then the old shortcuts setup by the MSYS2 installer may cease to function, and you can put a new shortcut on your desktop with that command. On Mon, Mar 26, 2018 at 6:02 PM, Simon Peyton Jones <simonpj@microsoft.com<mailto:simonpj@microsoft.com>> wrote: If the build environment is managed by an MSYS2 installation, then the MinGW64 shell startup script automatically sets up "MSYSTEM" for you. It can be launched like "C:\msys64\msys2_shell.cmd -mingw64 -mintty". Well I just followed the Method A instructions at https://ghc.haskell.org/trac/ghc/wiki/Building/Preparation/Windows Are you saying that I should run “C:\msys64\msys2_shell.cmd -mingw64 -mintty" just once, after installing? Or repeatedly? Or that I should somehow us it as my main shell? And what does that commend actually do? Sorry to be dense Simon From: ghc-devs <ghc-devs-bounces@haskell.org<mailto:ghc-devs-bounces@haskell.org>> On Behalf Of Shao, Cheng Sent: 26 March 2018 10:59 To: ghc-devs@haskell.org<mailto:ghc-devs@haskell.org> Subject: Re: Windows Hi Simon, If the build environment is managed by an MSYS2 installation, then the MinGW64 shell startup script automatically sets up "MSYSTEM" for you. It can be launched like "C:\msys64\msys2_shell.cmd -mingw64 -mintty". On Mon, Mar 26, 2018 at 5:46 PM, Simon Peyton Jones via ghc-devs <ghc-devs@haskell.org<mailto:ghc-devs@haskell.org>> wrote: Making it part of the error message would be v helpful. I have added a section to "Troubleshooting" on https://ghc.haskell.org/trac/ghc/wiki/Building/Preparation/Windows But it should really be part of the instructions higher up to sa export MSYSTEM=MINGW64 Might someone do that? I wasn't quite sure where Simon | -----Original Message----- | From: ghc-devs <ghc-devs-bounces@haskell.org<mailto:ghc-devs-bounces@haskell.org>> On Behalf Of Ben Gamari | Sent: 24 March 2018 16:42 | To: Gabor Greif <ggreif@gmail.com<mailto:ggreif@gmail.com>>; lonetiger@gmail.com<mailto:lonetiger@gmail.com> | Cc: ghc-devs@haskell.org<mailto:ghc-devs@haskell.org> | Subject: Re: Windows | | Gabor Greif <ggreif@gmail.com<mailto:ggreif@gmail.com>> writes: | | > Just an idea... | > | > could this hint be part of the `configure` error message? | > | Indeed. See D4526. | | Cheers, | | - Ben _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org<mailto:ghc-devs@haskell.org> http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs