[GHC] #11256: ghc --make reports bad import errors too eagerly
#11256: ghc --make reports bad import errors too eagerly -------------------------------------+------------------------------------- Reporter: ezyang | Owner: ezyang Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.11 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Consider this A.hs file, with a valid header (no B.hs file) and a syntax error: {{{ module A where import B = as7df89a235r a23jk @A#$(&#$A }}} We get different behavior when one-shot compiling and make compiling: {{{ ezyang@sabre:~$ ghc -c A.hs A.hs:4:1: parse error on input `=' ezyang@sabre:~$ ghc --make A.hs A.hs:2:8: Could not find module `B' Use -v to see a list of the files searched for. }}} I feel like the `--make` error is wrong, and we shouldn't actually complain that an import is missing until we build it. But it cuts both ways; if you have a big module graph and you try to `--make`, currently `--make` will report instantaneously if any import is wrong; if we changed this behavior, `--make` would chug along until it actually tried to compile the offending file. It's easy to fix and I can easily submit a patch for it, if people think we should defer the error. Doing this will also let me remove a grievous hack from my fix to #11244. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11256 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#11256: ghc --make reports bad import errors too eagerly -------------------------------------+------------------------------------- Reporter: ezyang | Owner: ezyang Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by thomie): You could try validating such a fix, if it really is not too much work. There might very well be a regression test against it. Then you could look to see if there is any discussion in the corresponding ticket. I am not sure which option is better from a users' perspective. I would go for the one that makes the implementation of `--make` the simplest. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11256#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#11256: ghc --make reports bad import errors too eagerly
-------------------------------------+-------------------------------------
Reporter: ezyang | Owner: ezyang
Type: bug | Status: new
Priority: normal | Milestone: 8.0.1
Component: Compiler | Version: 7.11
Resolution: | Keywords:
Operating System: Unknown/Multiple | Architecture:
| Unknown/Multiple
Type of failure: None/Unknown | Test Case:
Blocked By: | Blocking:
Related Tickets: | Differential Rev(s):
Wiki Page: |
-------------------------------------+-------------------------------------
Comment (by ezyang):
With the fix, three test cases see a diff like the following:
{{{
-Q.hs:3:8:
- Could not find module ‘Data.Set’
- It is a member of the hidden package
‘containers-@containers-’.
+Q.hs:3:1:
+ Failed to load interface for ‘Data.Set’
+ It is a member of the hidden package ‘containers-’.
Perhaps you need to add ‘containers’ to the build-depends in your
.cabal file.
Use -v to see a list of the files searched for.
}}}
Arguably, "Could not find module" is a better error message; however, this
is indeed the message `-c` gives when it can't find the module, so surely
it can't be that bad?
--
Ticket URL:
GHC
#11256: ghc --make reports bad import errors too eagerly -------------------------------------+------------------------------------- Reporter: ezyang | Owner: ezyang Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by thomie): Yeah, that seems fine. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11256#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#11256: ghc --make reports bad import errors too eagerly -------------------------------------+------------------------------------- Reporter: ezyang | Owner: ezyang Type: bug | Status: patch Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1669 Wiki Page: | -------------------------------------+------------------------------------- Changes (by ezyang): * status: new => patch * differential: => Phab:D1669 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11256#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#11256: ghc --make reports bad import errors too eagerly
-------------------------------------+-------------------------------------
Reporter: ezyang | Owner: ezyang
Type: bug | Status: patch
Priority: normal | Milestone: 8.0.1
Component: Compiler | Version: 7.11
Resolution: | Keywords:
Operating System: Unknown/Multiple | Architecture:
| Unknown/Multiple
Type of failure: None/Unknown | Test Case:
Blocked By: | Blocking:
Related Tickets: | Differential Rev(s): Phab:D1669
Wiki Page: |
-------------------------------------+-------------------------------------
Comment (by Ben Gamari
#11256: ghc --make reports bad import errors too eagerly -------------------------------------+------------------------------------- Reporter: ezyang | Owner: ezyang Type: bug | Status: closed Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.11 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1669 Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * status: patch => closed * resolution: => fixed -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11256#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
participants (1)
-
GHC