I am trying to learn Haskell with Atom ide on windows 7. I can build a program with stack but not with cabal. I wouldn't care about this except that Atom uses cabal. When I enter the command 'cabal build' I get the following messages: "Package has never been configured. Configuring with default flags. If this fails please run configure manually." "cabal: The program 'ghc' version >=6.4 is required but it could not be found." I have ghc version 7.10.3 installed which is >=6.4. So I guess it can't find the ghc compiler. Could somebody please advise?
You can find out where stack installs ghc by running stack path --ghc-paths.
Related
I installed Haskell on an M1 Mac following the official guide. During the installation, the following message was prompted:
System requirements
Note: On OS X, in the course of running ghcup you will be given a dialog box to install the command line tools. Accept and the requirements will be installed for you. You will then need to run the command again.
On Darwin M1 you might also need a working llvm installed (e.g. via brew) and have the toolchain exposed in PATH.
I additionally installed LLVM using homebrew:
brew install llvm#12
When trying ...
ghc --make <file>
... I get the following error message:
<no location info>: error:
Warning: Couldn't figure out LLVM version!
Make sure you have installed LLVM between [9 and 13)
ghc: could not execute: opt
How can I fix that? Or how can I go about the "have the toolchain exposed in PATH" part of the alert? I'm using ZSH, in case this is of relevance.
Probably not the best solution, but I got it working by adding /opt/homebrew/Cellar/llvm#12/12.0.1_1/bin to the PATH variable.
I'm trying to add the new llvm path to cabal to build with -fllvm option because I receive the error that it can't see the newer version:
<no location info>: error:
Warning: Couldn't figure out LLVM version!
Make sure you have installed LLVM 5.0
I have LLVM 5 installed under this path: /usr/local/Cellar/llvm#5/5.0.2/bin/. I need to somehow tell this to cabal but I can't find where to do this. In stack there is settings file under the installed ghc, but what is the wright way to do this for cabal?
I would start with
export PATH=/usr/local/Cellar/llvm#5/5.0.2/bin/:$PATH
cabal install
and see if that works.
I don't see any mention of options to set the LLVM path in the GHC user guide or the --with-PROG section of cabal configure --help. It certainly seems like a reasonable flag to add to cabal. The GHC guide only mentions finding it on PATH.
I'm trying to install ghc-mod for GHC 8.0.1 on windows/x64. When I try to install ghc-mod via cabal install ghc-mod I get an error saying my C compiler isn't working (it is using the c-compiler bundled with ghc).
Here is the output (of the second time I ran the command. Its basically what the first one says but reduced to the error message):
C:\Users\******>cabal install ghc-mod
Resolving dependencies...
Configuring old-time-1.1.0.3...
Failed to install old-time-1.1.0.3
Build log ( C:\Users\******\AppData\Roaming\cabal\logs\old-time-1.1.0.3.log ):
Configuring old-time-1.1.0.3...
bash.exe: warning: could not find /tmp, please create!
configure: WARNING: unrecognized options: --with-compiler
checking for gcc... C:\PROGRA~1\Haskell Platform\8.0.1\mingw\bin\gcc.exe
^ I think the error lies here, as you can see the file path is corrupted but I wasn't able to locate the cause for this
checking whether the C compiler works... no
configure: error: in `/cygdrive/c/Users/******/AppData/Local/Temp/cabal-tmp-6084/old-time-1.1.0.3':
configure: error: C compiler cannot create executables
See `config.log' for more details
cabal: Leaving directory 'C:\Users\******\AppData\Local\Temp\cabal-tmp-6084\old-time-1.1.0.3'
cabal: Error: some packages failed to install:
cpphs-1.20.2 depends on old-time-1.1.0.3 which failed to install.
ghc-mod-5.6.0.0 depends on old-time-1.1.0.3 which failed to install.
haskell-src-exts-1.17.1 depends on old-time-1.1.0.3 which failed to install.
hlint-1.9.35 depends on old-time-1.1.0.3 which failed to install.
old-time-1.1.0.3 failed during the configure step. The exception was:
ExitFailure 77
Could you please help me to install ghc-mod or provide any other way of installing it.
I already trieded reinstalling Haskell since I'm just starting off but this didn't make any difference.
And YES I added the 3 lines provided on the haskell homepage.
I can't know for certain, but thought I'd write an answer with what I think is going on.
The old-time package contains a configure script, which is a Unix shell script used to (surprise!) configure the package. The Cabal build system allows packages to automatically integrate configure, and will run the script for them. On POSIX systems, there's always a shell easily available. However, on Windows, that's not the case. I believe that's the problem you're running into.
Now the tricky part: why don't you have a shell? In theory, the Haskell Platform ships a shell. Well, here are my guesses:
For Stack usage, there's a Haskell Platform bug where Stack cannot find the MSYS tools, which include the shell script. Newer versions of Stack work around this bug, but passing in --no-system-ghc tells Stack to ignore any installed toolchain and manage the installation itself, which is more reliable than using HP's copy.
For Cabal usage, I'm less certain. I think the HP team decided to require you to use a special batch program to set environment variables correctly, so if you just run cabal install foo from a normal command window, Cabal won't find MSYS and it will fail. However, without more information, I can't be certain this is the case.
My personal recommendation: uninstall Haskell Platform, and use the recommended Stack installation instructions. In your case, that's just downloading and running the 64-bit Windows installer.
Finally: your suspected problem is not actually a problem; on Windows, pathnames longer than 8 characters can be compressed in the way you see (with ~1 at the end). There's nothing buggy in that path display.
If I start up a new project, add hfsevents to the list of dependencies in the .cabal file, and run stack build, I get an error (on Mac OSX Yosemite):
-- While building package hfsevents-0.1.6 using:
/Users/Me/.stack/setup-exe-cache/setup-Simple-Cabal-1.22.4.0-x86_64-osx-ghc-7.10.2 --builddir=.stack-work/dist/x86_64-osx/Cabal-1.22.4.0/ build --ghc-options -hpcdir .stack-work/dist/x86_64-osx/Cabal-1.22.4.0/hpc/.hpc/ -ddump-hi -ddump-to-file
Process exited with code: ExitFailure 1
Logs have been written to: /Users/Me/Desktop/code/haskell/test/.stack-work/logs/hfsevents-0.1.6.log
Configuring hfsevents-0.1.6...
Building hfsevents-0.1.6...
Preprocessing library hfsevents-0.1.6...
[1 of 1] Compiling System.OSX.FSEvents ( System/OSX/FSEvents.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.4.0/build/System/OSX/FSEvents.o )
gcc: error: language objective-c not recognized
gcc: error: language objective-c not recognized
I already followed the advice of calling brew install gcc48 --with-all-languages and I uninstalled all Haskell versions, only using the ghc within stack. Xcode is on version 7.1.1. What else can I try to fix this problem?
Eventually got this working. The steps that led me to the solution are documented here: https://github.com/commercialhaskell/stack/issues/1563
Basically, I had two different gcc's installed, one in /usr/bin/ installed by Xcode and one in /usr/local/bin/ from somewhere I don't remember. /usr/bin/gcc was the one being used by cabal, so cabal install hfsevents worked, while /usr/local/bin/gcc, which was the one apparently being used by stack, had this issue. What I did to resolve this was delete /usr/local/bin/gcc and only keep /usr/bin/gcc.
I was trying to install wxHaskell into a machine running Windows XP64, with MinGW/MSYS and wxWidget 3.0 built from source using gcc. I did:
cabal install wx
and got an error:
...
Configuring wxc-0.90.0.4...
setup.exe: wx-config: does not exist
Failed to install wxc-0.90.0.4
cabal.exe: Error: some packages failed to install:
wx-0.90.0.1 depends on wxc-0.90.0.4 which failed to install.
wxc-0.90.0.4 failed during the configure step. The exception was:
ExitFailure 1
wxcore-0.90.0.3 depends on wxc-0.90.0.4 which failed to install.
I had successfully used wxWidgets to write an sample application in C++ (gcc). So I do have a working wxWidget installation. And I have wx-config at:
$ which wx-config
/usr/local/bin/wx-config
The problem is that wx-config is a unix shell script, and cabal (called from MSYS) somehow refuses to recognize it even if it's on the system path. If I run wx-config in MSYS, I get something like:
$ wx-config --cxxflags
-I/usr/local/lib/wx/include/msw-unicode-3.0 -I/usr/local/include/wx-3.0 -D_LARGE
FILE_SOURCE=unknown -DWXUSINGDLL -D__WXMSW__ -mthreads
I have asked a question https://stackoverflow.com/questions/21998763/how-to-convert-msys-shell-scripts-to-windows-exe-files to see if it's possible to convert the script to an exe, but no one responded with any solutions.
There is also a related question here, wxHaskell installation on windows , and another here wx 0.90.0.1 fails to install on Haskell Platform 2012.2.0.0 (WinXP). In fact, I couldn't found an answer that's confirmed to work. Also, the errors/settings here seem to be different, or the answers therein don't seem solve my problem. In particular, I downloaded an external wx-config.exe from https://sourceforge.net/projects/wxhaskell/files/wx-config-win/ per http://www.haskell.org/haskellwiki/WxHaskell/Windows. But running wx-config.exe can't recognize my wxWidget installation and always gives me an error about cannot find wxWidgets, like this:
$ ./wx-config.exe --prefix=/usr/local/
wx-config Error: wxWidgets hasn't been found installed at 'C:\MinGW\msys\1.0\loc
al'.
Please use the --prefix flag (as in wx-config --prefix=C:\wxWidgets)
or set the environment variable WXWIN (as in WXWIN=C:\wxWidgets)
to specify where is your installation of wxWidgets.
Any idea how to work around this issue?
Thanks,
-- Update --
#JP I tried:
C:\temp\wxdirect-0.90.0.1>runhaskell Setup configure --extra-lib-dirs=c:\MinGW\lib --extra-include-dirs=c:\MinGW\include --extra-include-dirs=c:\MinGW\msys\1.0\local\include
Configuring wxdirect-0.90.0.1...
and got
Setup: At least the following dependencies are missing:
containers >=0.2 && <0.5, strict -any
I tweaked wxdirect.cabal to bypass containers >=0.2 && <0.5, but can't get pass strict.
I've written a powershell script that automates the setup of MinGW and the downloading/building of wxWidgets in order to build wxHaskell for Windows 7.
https://github.com/cessationoftime/wxHaskell-Windows-Builder