The first one is not a severe bug, but nevertheless: When using
declare, Green Card omits a C type cast. Consider the following
(silly) GC spec:
--------------------------------------------------
module Cast where
import StdDIS
newtype Foo = B Word32
%dis foo b = B (declare {FILE*} b in (word32 b))
%fun bar :: Foo -> IO Char
%call (foo b)
%code r = fgetc(b);
%result (char r)
--------------------------------------------------
This is converted to:
--------------------------------------------------
module Cast where
import StdDIS
newtype Foo = B Word32
bar :: Foo -> IO Char
bar gc_arg1 =
case gc_arg1 of { (B b) ->
_casm_ ``do {FILE* b;char r;
b = %0;
do { r = fgetc(b);
%r = (char)(r);} while(0);} while(0);'' b
>>= \ r ->
(return (r))}
--------------------------------------------------
The "b = %0;" should be "b = (FILE*)%0;", otherwise gcc complains
about making a pointer from an integer without a cast. That this
should be correct has already been stated in the DIS.
Another point is user-defined marshalling with more than one argument.
The Green Card from York seems to interpret this as implicit tupling,
so (I guess) the following should be fine:
--------------------------------------------------
module Strange where
import StdDIS
data Foo = F Int Char
%dis foo x y = <fromFoo/toFoo> (int x) (char y)
fromFoo (F i c) = (i,c)
toFoo (i,c) = F i c
%fun bar :: Foo -> IO ()
%call (foo a b)
%code baz(a, b);
--------------------------------------------------
But, alas, it isn't:
--------------------------------------------------
module Strange where
import StdDIS
data Foo = F Int Char
fromFoo (F i c) = (i,c)
toFoo (i,c) = F i c
bar :: Foo -> IO ()
bar gc_arg1 =
case (fromFoo gc_arg1) of { a ->
_casm_ ``do {int a;
a = %0;
do { baz(a, b);
} while(0);} while(0);'' a}
--------------------------------------------------
Somehow the b disappeared... :-(
Bug, feature, or an uncool DIS again? ;-)
[ BTW, the GHC port of the Binary lib is up and running, but it
needs a little bit of testing before I dare to release it... ]
--
Sven Panne Tel.: +49/89/2178-2235
LMU, Institut fuer Informatik FAX : +49/89/2178-2211
LFE Programmier- und Modellierungssprachen Oettingenstr. 67
mailto:[EMAIL PROTECTED] D-80538 Muenchen
http://www.pms.informatik.uni-muenchen.de/mitarbeiter/panne
