#14460: Can't decompose ghc.exe path -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by astert): Oh, no it didn't. That must just be how it formats here. The path has double slashes. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Can't decompose ghc.exe path -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Phyx-): Ah ok thanks, so does `"H:\\Programs\\Haskell\\8.2.1\\lib` exist? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Can't decompose ghc.exe path -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Phyx-): No, your `lib` folder, not the `bin` folder. The path I pasted is different from the one you reported. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Can't decompose ghc.exe path -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by astert): Can confirm that the lib directory does exist. I'll try uninstalling and reinstalling it and see if the problem persists. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Can't decompose ghc.exe path -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Phyx-): What kind of drive is your `H:\` drive? just a normal harddisk? what's the OS and file system of the drive? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Can't decompose ghc.exe path -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by Phyx-): * cc: Phyx- (added) Comment: You can right click on the drive and choose properties. It should tell you what file system it is. I have never tried this from a network drive. Most likely we're getting an access denied when trying to resolve the path on the network drive. It could also be network instability as Smb can be unstable when doing file attribute checks. I'll see if I can't special case network mounts. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Symlink resolving fails against SMB mounts -------------------------------------+------------------------------------- Reporter: astert | Owner: Phyx- Type: bug | Status: new Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by Phyx-): * owner: (none) => Phyx- * milestone: => 8.4.1 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Symlink resolving fails against SMB mounts -------------------------------------+------------------------------------- Reporter: astert | Owner: Phyx- Type: bug | Status: patch Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4216 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari ): In [changeset:"62823668c48e13290e2ffe0d593a9f6a95cf628b/ghc" 62823668/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="62823668c48e13290e2ffe0d593a9f6a95cf628b" Follow symlinks in the Win32 code for System.Environment.getExecutablePath This partially addresses #14483 by fixing the Windows implementation of System.Environment.getExecutablePath. This is achieved by using GetFinalPathNameByHandleW to resolve potential symlinks, while making sure we do not get back a UNC path (see #14460). Test Plan: Validate Reviewers: Phyx, bgamari, angerman, hvr, goldfire Reviewed By: Phyx, bgamari GHC Trac Issues: #14483 Differential Revision: https://phabricator.haskell.org/D4227 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Symlink resolving fails against SMB mounts -------------------------------------+------------------------------------- Reporter: astert | Owner: Phyx- Type: bug | Status: closed Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1 Resolution: fixed | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4216 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Vyse007): I am still facing this exact issue with 8.4.3. On a mounted network drive (shows up as "Network Drive, NTFS" under "This PC" on Windows 10), installing GHC and then invoking it throws the following error (Z is the networked drive): {{{ PS Z:\sandbox\Vyse\8.4.3> cd .\bin\ PS Z:\sandbox\Vyse\8.4.3\bin> .\ghci ghc.exe: panic! (the 'impossible' happened) (GHC version 8.4.3 for x86_64-unknown-mingw32): can't decompose ghc.exe path: "Z:\\sandbox\\Vyse\\8.4.3\\bin\\ghc.exe" }}} I originally thought this error must be because `doesDirectoryExist` returns false when trying to decompose this path, but that's not the case... (Note that the `ghci` used below is the one currently on PATH, i.e., not on the networked drive) {{{ PS Z:\sandbox\Vyse\8.4.3\bin> ghci GHCi, version 8.4.3: http://www.haskell.org/ghc/ :? for help Prelude> import System.Directory Prelude System.Directory> doesDirectoryExist "Z:\\sandbox\\Vyse\\8.4.3\\bin\\" True }}} It might be worth noting that I don't have write permissions for all of `Z:\`, but only for my own folder there. I am willing to debug this further but I don't really know how to. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:18 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Symlink resolving fails against SMB mounts -------------------------------------+------------------------------------- Reporter: astert | Owner: Phyx- Type: bug | Status: closed Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1 Resolution: fixed | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4216 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Vyse007): So for some strange weirdness with `autoconf` I can't actually test my fix, but sleuthing with APIMonitor as suggested by Phyx- leads me to the following conclusion: In the `getBaseDir` function in `BaseDir.hs`, the value of `GetModuleFileName` is indeed `Z:\sandbox\Vyse\8.4.3\bin\ghc.exe` - APIMonitor confirms this. This function then calls `getFinalPath` defined under it, which attempts to find the 'final' path of the executable. This function internally calls `GetFinalPathNameByHandleW`, and this function returns a slightly different value (after adding the backslashes): `\\\\?\\UNC\\vNetwork\\users\\sandbox\\Vyse\\8.4.3\\bin\\ghc.exe` - again, as reported by APIMonitor. Now calling `sanitize` and `takeDirectory` (twice) gets rid of the preceding `\\\\?\\`, but still leaves us with `UNC\\vNetworks\\users\\sandbox\\Vyse\\8.4.3`. This directory, according to `doesDirectoryExist`, does not exist. And that is correct in a way, as you cant `cd` to that location with that path, but you can use (without the extra slashes) `cd \\vNetwork\users\sandbox...` Anyway, API monitor reports that after the `GetFinalPathNameByHandleW` call, which returns the value with the `UNC` prefix, we end up calling `CreateFileW` again, but this time with the bizarre value of `\\?\Z:\sandbox\Vyse\8.4.3\bin\UNC\vNetwork\users\sandbox\Vyse\8.4.3\lib` - not sure where this came from, but at this point `NtCreateFile` errors out. I'll look into it a bit more when I get some time. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:20 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Symlink resolving fails against SMB mounts -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: patch Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4216 Wiki Page: | Phab:D4229 Phab:D4227 -------------------------------------+------------------------------------- Changes (by Phyx-): * status: new => patch -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:22 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#14460: Symlink resolving fails against SMB mounts -------------------------------------+------------------------------------- Reporter: astert | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.2.1 Resolution: fixed | Keywords: Operating System: Windows | Architecture: Type of failure: GHC doesn't work | Unknown/Multiple at all | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4216 Wiki Page: | Phab:D4229 Phab:D4227 -------------------------------------+------------------------------------- Changes (by Phyx-): * status: patch => closed * resolution: => fixed * milestone: 8.4.1 => 8.6.1 Comment: In c523525/ghc: ghc, ghc-pkg: use getExecutablePath on Windows when base >= 4.11.0 Summary: This completes the work started in D4227 by using just 'getExecutablePath' in ghc and ghc-pkg when building with base >= 4.11.0. On the long term, we will be able to simply kill the existing code that follows (or not) symlinks and just get this behaviour for free from getExecutable. For now we however have to require base >= 4.11.0 to be able to just use getExecutablePath under Windows, and use the current code when building with an older base. Original code by @alpmestan commandeering since patch has been stale and bug remains open. Test Plan: Validate Reviewers: angerman, bgamari, erikd, alpmestan Reviewed By: bgamari Subscribers: carter, rwbarton, thomie GHC Trac Issues: #14483 Differential Revision: https://phabricator.haskell.org/D4229 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14460#comment:24 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler