FFI Bug - Finalizer always called with NULL pointer?
brianh at metamilk.com
Sat Apr 8 04:39:40 EDT 2006
By just using the following syntax, GHC compiles everything correctly:
foreign import ccall
"&duma_releaseFont" -- absolutely vital for FunPtr functions
:: FunPtr (Ptr RawFont -> IO ())
which now gives (correctly):
call "ccall" suspendThread((BaseReg, NoHint))[(_c3be, NoHint)];
call "ccall" duma_releaseFont((_s365, PtrHint)); // SPLENDID WORK GHC !!!!
call "ccall" resumeThread((_c3be, NoHint));
So it seems there is something ***very*** special about the
"&duma_releaseFont" syntax whereas I'd have thought that the meaning of:
foreign import ccall duma_releaseFont
:: FunPtr (Ptr RawFont -> IO ()) -- DANGEROUSLY BAD :-(
should be absolutely identical. However it is not. I'm not sure whether or
not to report this as a bug since it certainly tripped me up, and it was
only by some lucky detective work that I discovered what was happening.
Is there supposed to be a difference or is this just a bug?
In any case - problem solved,
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