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[c2hs] #53: Cabal Install failed with ghc 7.6.1
by c2hs 09 Feb '13

09 Feb '13

#53: Cabal Install failed with ghc 7.6.1 --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.2 | Keywords: --------------------+------------------------------------------------------- Fail to install using ghc 7.6.1. Two changes are needed, but I don't know if backward compatible. Émeric diff -r c2hs-0.16.3_bu/src/C2HS/Config.hs c2hs-0.16.3/src/C2HS/Config.hs 40c40 < import Foreign.C (CInt) --- > import Foreign.C (CInt(..)) diff -r c2hs-0.16.3_bu/src/Control/StateTrans.hs c2hs-0.16.3/src/Control/StateTrans.hs 75a76 > import System.IO.Error(catchIOError) 299c300 < `catch` (\err -> let --- > `catchIOError` (\err -> let -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/53> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #49: Run return value marshaller before output parameter marshallers
by c2hs 09 Feb '13

09 Feb '13

#49: Run return value marshaller before output parameter marshallers --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.0 | Keywords: --------------------+------------------------------------------------------- Many C functions provide an error code as a return value, and have output parameters that they do not set unless the return value indicates success. Handling such functions requires checking the return value before running any output marshallers. The reverse situation (an error code as an output parameter that needs checking before the return value) almost never occurs. Thus, run the return value marshaller before the output parameter marshallers, so that the return value marshaller can generate an exception that will prevent the output marshallers from running. {{{ diff -rN -u old-c2hs/src/C2HS/Gen/Bind.hs new-c2hs/src/C2HS/Gen/Bind.hs --- old-c2hs/src/C2HS/Gen/Bind.hs 2012-10-07 19:22:14.515183247 -0700 +++ new-c2hs/src/C2HS/Gen/Bind.hs 2012-10-07 19:22:14.515183247 -0700 @@ -894,8 +894,8 @@ funBody = joinLines marshIns ++ mkMarsh2 ++ call ++ - joinLines marshOuts ++ marshRes ++ + joinLines marshOuts ++ " " ++ (if isImpure || not isPure then "return " else "") ++ ret return $ sig ++ funHead ++ funBody }}} -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/49> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #50: Parenthesize marshallers, to preserve Haskell expressions
by c2hs 09 Feb '13

09 Feb '13

#50: Parenthesize marshallers, to preserve Haskell expressions --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.0 | Keywords: --------------------+------------------------------------------------------- Marshallers can contain Haskell expressions; however, c2hs substitutes those expressions into Haskell code as function calls and adds arguments to the end, which limits these Haskell expressions to simple function calls with one or more arguments. Add parentheses to these expressions, allowing them to contain arbitrary Haskell expressions with lower precedence than function calls, such as operators. {{{ diff -rN -u old-c2hs/src/C2HS/Gen/Bind.hs new-c2hs/src/C2HS/Gen/Bind.hs --- old-c2hs/src/C2HS/Gen/Bind.hs 2012-10-07 19:24:21.493527302 -0700 +++ new-c2hs/src/C2HS/Gen/Bind.hs 2012-10-07 19:24:21.521526937 -0700 @@ -884,7 +884,7 @@ interr "GenBind.funDef: marshRes: no default?" marshBody (Left ide) = identToString ide - marshBody (Right str) = str + marshBody (Right str) = "(" ++ str ++ ")" retArgs' = case parm' of CHSParm _ _ _ (Just (_, CHSVoidArg)) _ -> retArgs @@ -962,7 +962,7 @@ retArg = if omArgKind == CHSVoidArg || omArgKind == CHSIOVoidArg then "" else outBndr marshBody (Left ide) = identToString ide - marshBody (Right str) = str + marshBody (Right str) = "(" ++ str ++ ")" in (funArg, marshIn, callArgs, marshOut, retArg) marshArg _ _ = interr "GenBind.funDef: Missing default?" }}} -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/50> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #54: Allow referring to 'struct foo' identifiers from {#sizeof} {#get} and friends
by c2hs 17 Oct '12

17 Oct '12

#54: Allow referring to 'struct foo' identifiers from {#sizeof} {#get} and friends --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.0 | Keywords: --------------------+------------------------------------------------------- C maintains separate namespaces for 'struct foo' and 'typedef ... foo', and at present c2hs only references the latter namespace. This is annoying if a library author didn't add typedefs to allow eliding the 'struct' keyword from type definitions; we have to re-typedef everything we want to use from c2hs. It would be convenient if we could write {#get struct foo->bar #} or similar. Note that pointer appears to look in both namespaces, so I don't know what's going on there. -- ezyang -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/54> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #51: Should not define preprocessor symbols for GCC
by c2hs 08 Oct '12

08 Oct '12

#51: Should not define preprocessor symbols for GCC --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.0 | Keywords: --------------------+------------------------------------------------------- c2hs uses GCC's preprocessor, and as a result it parses C code with GCC's default preprocessor symbols defined. Many projects rely on those preprocessor symbols to decide whether to use GCC-specific extensions, such as {{{__attribute__}}} declarations. Since c2hs does not support those extensions, it should not define those preprocessor symbols. Please consider invoking the preprocessor with {{{-U__GNUC__ -U__GNUC_MINOR__ -U__GNUC_PATCHLEVEL__}}} . -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/51> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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Re: [C2hs] [c2hs] #5: support for enum define hooks
by c2hs 07 Oct '12

07 Oct '12

#5: support for enum define hooks --------------------+------------------------------------------------------- Reporter: guest | Type: enhancement Status: new | Priority: normal Milestone: | Component: general Version: 0.15.1 | Keywords: --------------------+------------------------------------------------------- Comment(by guest): c2hs has had enum define for a while now. -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/5#comment:1> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #48: Interpreted an int64_t typedef as CInt
by c2hs 05 Jul '12

05 Jul '12

#48: Interpreted an int64_t typedef as CInt --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: blocker Milestone: | Component: general Version: 0.16.2 | Keywords: --------------------+------------------------------------------------------- A library I'd like to write bindings to has a typedef of int64_t to a library-specific type name. c2hs seems to interpret that type as CInt, both in foreign import declarations and in {# type #} directives. It should interpret that type as a 64-bit integer type instead. -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/48> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #47: Void functions produce a "defined but not used" warning for the result
by c2hs 04 Jul '12

04 Jul '12

#47: Void functions produce a "defined but not used" warning for the result --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.0 | Keywords: --------------------+------------------------------------------------------- Declaring a {# fun ... #} with return type `()' leads to the following warning from GHC: Warning: Defined but not used: `res' Please consider either using res or declaring it as _ in this case, to prevent the warning. -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/47> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #46: No way to create a foreign pointer for input and have it as an out parameter
by c2hs 04 Jul '12

04 Jul '12

#46: No way to create a foreign pointer for input and have it as an out parameter --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.0 | Keywords: --------------------+------------------------------------------------------- I have quite a few C functions like this: ... func(oid *, ...); oid refers to a non-opaque C struct, and these functions treat it as an out parameter; a C caller would define an instance of the struct (knowing its size) and pass the address of that structure to have it filled in. I'd like to allocate memory for this struct using mallocForeignPtrBytes {# sizeof oid #}, pass the underlying Ptr to the function, and then return the foreign pointer wrapped in an opaque type (defined using {# pointer ... foreign newtype #}). Note that the documentation for mallocForeignPtrBytes specifically says that GHC implements it much more efficiently than a standard ForeignPtr with a finalizer of finalizerFree; otherwise, I could just use malloc and then wrap the pointer on the way out. As far as I can tell, a {# fun ... #} wrapper cannot implement this pattern. Any output marshaller has to work using the same value passed to the function, which in this case would be a Ptr, not a ForeignPtr. Thus, I can't both create an OID in the input marshaller (using a - so the caller doesn't have to pass one) and return that OID from the function. At the moment, I've come up with three workarounds, none of which work very well: - Write a {# fun ... #} wrapper using withOID* and write a Haskell wrapper function that calls newOID first, requiring an extra five lines for every function using an OID. - Give up on mallocForeignPtrBytes and use malloc on input and newForeignPtr on output, with resulting inefficiency (the library uses a *lot* of these structures). - Use alloca on input, and have the output marshaller use mallocForeignPtrBytes and make a copy. Efficient use of memory and efficient reclamation, but an extra copy per call. Ideally, I'd prefer to have a way to declare this pattern directly in a marshaller. I'd suggest adding a new symbol to apply to the input marshaller, which allows it to provide an output directly. -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/46> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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[c2hs] #45: Please indent all output lines from a {# fun ... #} to match the input indentation, to allow it in a where clause
by c2hs 04 Jul '12

04 Jul '12

#45: Please indent all output lines from a {# fun ... #} to match the input indentation, to allow it in a where clause --------------------+------------------------------------------------------- Reporter: guest | Type: defect Status: new | Priority: normal Milestone: | Component: general Version: 0.16.0 | Keywords: --------------------+------------------------------------------------------- I tried to declare a {# fun ... #} in a where clause, but only the first line had the proper indentation, causing GHC to complain that "The type signature for `foo' lacks an accompanying binding" (because only the type signature appeared within the where clause). Please consider indenting all lines of a {# fun ... #} to match the input indentation, so that this works. -- Ticket URL: <http://hackage.haskell.org/trac/c2hs/ticket/45> c2hs <http://www.cse.unsw.edu.au/~chak/haskell/c2hs/> C->Haskell, An Interface Generator for Haskell

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