From: Asfand Yar Qazi <im_not_giving_it_here@..._hate_spam.com>
Date: 2004-01-18T18:49:59+09:00
Subject: Re: C++ from Ruby ARRRGGHH!!

nobu.nokada@softhome.net wrote:
> Hi,
> 
> At Sun, 18 Jan 2004 16:20:01 +0900,
> Asfand Yar Qazi wrote:
> 
>>Anyway, could you look at the following test code that reveals the 
>>problem?  I just don't know what to do!  Are C++ exceptions in GCC 
>>incompatible with Ruby exceptions?  I think that's the problem, isn't it...
> 
> 
> Yes, of course, incompatible.  They aren't concerned with at
> all.  You have to protect or wrap each exceptions at every
> boundaries.
> 

As you can see from the code...

#define CHECK_CPP(code) try {code;} \
	   catch(std::exception& e) {raise_ruby(e);}

i.e. catch a C++ exception, wrap its contents in a Ruby exception, 
dispatch that Ruby exception.  But that corrupts the program stack I 
think, resulting in really funny and annoying errors (as documented in 
the OP), and eventually resulting in a coredump.  Its all due to the 
setjmp/longjmp used by Ruby exceptions and GCC's advanced 
exception-handling mechanism, which are incompatible.

I wait for the day when a scripting language will be written in C++, and 
be fully compatible will C++ features (perhaps even with templates.) 
But still, I'll just redo my C++ code in a Ruby-esque way, i.e. throwing 
Ruby exceptions instead of C++ exceptions, so no problems.

--
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