GHCi linker failure on Windows

On Windows, GHCi seems unable to find a DLL in a non-standard location, even when that location is provided with -L.

Presume a valid DLL named "foo.dll" in "c:\temp\test". An attempt to load "foo" into GHCi when the current working directory is "c:\temp\test" is successful:

C:\temp\test>ghci -lfoo
GHCi, version 6.12.3: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
Loading object (dynamic) foo ... done
final link ... done
Prelude>

However, if the current working directory is "c:\temp" all attempts to load "foo" into GHCi using the -L switch fail:

C:\temp>ghci -lfoo -Ltest
GHCi, version 6.12.3: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
: foo: The specified module could not be found.
Loading object (dynamic) foo ... failed.
<command line>: user specified .o/.so/.DLL could not be loaded (addDLL: could no
t load DLL)
Whilst trying to load:  (dynamic) foo
Additional directories searched:   test

C:\temp>ghci -lfoo -L\temp\test
GHCi, version 6.12.3: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
: foo: The specified module could not be found.
Loading object (dynamic) foo ... failed.
<command line>: user specified .o/.so/.DLL could not be loaded (addDLL: could no
t load DLL)
Whilst trying to load:  (dynamic) foo
Additional directories searched:   \temp\test

C:\temp>ghci -lfoo -Lc:\temp\test
GHCi, version 6.12.3: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
: foo: The specified module could not be found.
Loading object (dynamic) foo ... failed.
<command line>: user specified .o/.so/.DLL could not be loaded (addDLL: could no
t load DLL)
Whilst trying to load:  (dynamic) foo
Additional directories searched:   c:\temp\test

However, GHCi has no problem loading "foo" if the path component is included in the -l option. (Naturally, this is not ideal and far from the accepted usage of -l and -L.)

C:\temp>ghci -ltest\foo
GHCi, version 6.12.3: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
Loading object (dynamic) test\foo ... done
final link ... done
Prelude>

Finally, this issue does not manifest on Linux. Everything seems to work fine there.

Trac metadata

Trac field	Value
Version	6.12.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	GHCi
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	joell@sunbeltsoftware.com
Operating system
Architecture