On Wed, 2005-11-02 at 18:05 +0100, Florian Weimer wrote:
Is it correct that you use indirect gotos across functions? Such gotos aren't supported by GCC and work only by accident.
Even direct gotos aren't universally supported. Some info in Fergus Henderson's paper may be of interest
This paper seems to be from 1995 or so:
%DVIPSSource: TeX output 1995.11.29:1656
(Why is it so uncommon to put the publication date on the first page?)
GCC's IL has changed significantly since then; it's not clear if it still applies.
I am using some of it in Felix, that part I am using seems to work fine on all platforms tested: various versions of g++ and under Linux, OSX, Cygwin, and MinGW, possibly more. The config script checks assembler labels are supported, if they are the indirect jumps 'just work'. Of course the config would have to be built by hand for cross compilation ;( However my system obeys a constraint: the runtime conspires to ensure the function containing the target label is entered before the jump is done. The address is calculated by the caller though. So I don't run into any problems loading the right data section pointer. I suspect Haskell cannot do that, since it would defeat the intended optimisation. [More precisely, in Felix the technique is used to implement non-local gotos, and which can only occur in procedures, not in functions] -- John Skaller <skaller at users dot sf dot net> Felix, successor to C++: http://felix.sf.net