GHC 6.10.1 Win32 release is unusable (on XP SP3)

[guest]

1. Running ghc in cmd.exe shell delivers (in my config):

ghc.EXE: panic! (the 'impossible' happened)

(GHC version 6.10.1 for i386-unknown-mingw32):

can't decompose ghc.exe path: "G:\\Progs\\ghc-6.10.1\\Bin\\ghc.exe"

2. runghc.exe/runhaskell.exe hangs.

3. $topdir\include\mingw\c++ contains subtrees "3.4.5" and "3.4.2". "3.4.2" seems completely irrelevant here.

[NeilMitchell]

I fixed a similar issue in 6.9, and at that point wondered if other changes needed making - obviously the answer is yes. I'll track this one down and get a patch.

I suspect this relates to either your shell, or your %PATH% - do you have "G:\Progs\ghc-6.10.1\Bin" on your path, and does changing it to "\bin" fix the issue?

[NeilMitchell]

Patch

[NeilMitchell]

I've attached a patch, which I think should fix the issue. This probably needs to be merged in to 6.10 as well. I haven't tested the patch (other than it compiles), but its fairly simple, so hopefully will work.

When was getBaseDir altered? If this code is new for 6.10, then it is almost certainly worth releasing a new version for Windows. Depending on peoples setups, it could be quite common.

[guest]

Yes, changing "G:\Progs\ghc-6.10.1\Bin" to "G:\Progs\ghc-6.10.1\bin" in my %PATH% have fixed the ghc.exe issue, but runghc/runhaskell still hangs.

[NeilMitchell]

The PATH thing has a patch, is a known issue, so that seems to be eliminated.

The issue with runghc is that "runghc" with no arguments takes the file from stdin. i.e. type "runghc" then type "main = print 1" enter, then hit Ctrl+Z and enter. That will print the number 1 to the screen. This isn't how most Windows programs behave, and trying "runghc --help" has exactly the same behaviour (i.e. an apparent hang) so its not very helpful.

There is a bug on my 6.9 thing that hitting Ctrl+C does not abort runghc while typing in a script, and that is a bug, if it is the same with 6.10.

So I guess the runghc should respond more helpfully to --help, and should abort on Ctrl+C. Should it also print some help text for windows users with stdin bound to the prompt? Seems a bit of a horrid special case, but might help.

[guest]

Well, I conjectured something like this about runghc, but didn't bother to test it out since it wasn't an issue for 6.8.3: runghc.exe: syntax: runghc [-f GHC-PATH | --] [GHC-ARGS] [--] FILE ARG...

[simonmar]

I'll validate and commit, thanks. The runghc bugs have been separately ticketed as #2757 and #2758.

[simonmar]

Validated and pushed:

Wed Nov  5 05:43:15 PST 2008  Neil Mitchell <ndmitchell@gmail.com>
  * Perform case-insensitive matching of path components in getBaseDir on Windows (Fixes bug 2743)

we should check that it actually fixes the bug, though.

[igloo]

Merged. Ticket left open for fix verification.

[NeilMitchell]

I've built with the fix, and tested, and it works:

C:\ghc>ghc-6.8.3\BIN\ghc.exe
ghc.exe: no input files
Usage: For basic information, try the `--help' option.

C:\ghc>ghc-6.9.20080905\BIN\ghc.exe
ghc.exe: panic! (the 'impossible' happened)
  (GHC version 6.9.20080905 for i386-unknown-mingw32):
        can't decompose ghc.exe path: "C:\\ghc\\ghc-6.9.20080905\\BIN\\ghc.exe"

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

C:\ghc>ghc-6.11.20081111\BIN\ghc.exe
ghc.exe: no input files
Usage: For basic information, try the `--help' option.