llvm dev - Jul 2011 - [LLVMdev] Catching exceptions passed through a JIT ExecutionEngine

Hi All,

I'm trying to catch an exception that is "passed through" an LLVM
ExecutionEngine but I am unable to do so.  Specifically, in C++ code, inside a
try/catch block, I call a JITted function, which in turn calls back into my
code.  Everything works fine unless an exception is thrown; I would except the
outermost try/catch(...) block to catch the exception thrown in my innermost C++
code, but instead I get the abort "terminate called after throwing an
instance of 'MyException'".  I am compiling the system with g++ (on
Linux and OSX); I haven't tried MSVC++.

Is there something that I need to do to get this behaviour to work?  I admit
that I have only a fairly basic understanding of how exception handling is
implemented in C++ but from what I've read it seems like the exception
should unwind through what is, for all intents and purposes, a simple call
stack...

Thanks,
Peter Zion

Sorry Peter, just saw this.

If you are still having the problem:

Did you set: llvm::JITExceptionHandling = true; ?

Garrison

On Jul 12, 2011, at 19:25, Peter Zion wrote:
> Hi All,
> 
> I'm trying to catch an exception that is "passed through" an
LLVM ExecutionEngine but I am unable to do so.  Specifically, in C++ code,
inside a try/catch block, I call a JITted function, which in turn calls back
into my code.  Everything works fine unless an exception is thrown; I would
except the outermost try/catch(...) block to catch the exception thrown in my
innermost C++ code, but instead I get the abort "terminate called after
throwing an instance of 'MyException'".  I am compiling the system
with g++ (on Linux and OSX); I haven't tried MSVC++.
> 
> Is there something that I need to do to get this behaviour to work?  I
admit that I have only a fairly basic understanding of how exception handling is
implemented in C++ but from what I've read it seems like the exception
should unwind through what is, for all intents and purposes, a simple call
stack...
> 
> Thanks,
> Peter Zion
> 
> 
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev

Yes, I did -- it made no difference.  Should it?

Note that I have since discovered that this is not a problem on Windows -- the
exception drops through as expected.

pz

On 2011-07-21, at 5:45 PM, Garrison Venn wrote:
> Sorry Peter, just saw this.
> 
> If you are still having the problem:
> 
> Did you set: llvm::JITExceptionHandling = true; ?
> 
> Garrison
> 
> On Jul 12, 2011, at 19:25, Peter Zion wrote:
> 
>> Hi All,
>> 
>> I'm trying to catch an exception that is "passed through"
an LLVM ExecutionEngine but I am unable to do so.  Specifically, in C++ code,
inside a try/catch block, I call a JITted function, which in turn calls back
into my code.  Everything works fine unless an exception is thrown; I would
except the outermost try/catch(...) block to catch the exception thrown in my
innermost C++ code, but instead I get the abort "terminate called after
throwing an instance of 'MyException'".  I am compiling the system
with g++ (on Linux and OSX); I haven't tried MSVC++.
>> 
>> Is there something that I need to do to get this behaviour to work?  I
admit that I have only a fairly basic understanding of how exception handling is
implemented in C++ but from what I've read it seems like the exception
should unwind through what is, for all intents and purposes, a simple call
stack...
>> 
>> Thanks,
>> Peter Zion
>> 
>> 
>> _______________________________________________
>> LLVM Developers mailing list
>> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>

On Tue, Jul 12, 2011 at 07:25:16PM -0400, Peter Zion
said
> Hi All,
> 
> I'm trying to catch an exception that is "passed through" an
LLVM ExecutionEngine but I am unable to do so.  Specifically, in C++ code,
inside a try/catch block, I call a JITted function, which in turn calls back
into my code.  Everything works fine unless an exception is thrown; I would
except the outermost try/catch(...) block to catch the exception thrown in my
innermost C++ code, but instead I get the abort "terminate called after
throwing an instance of 'MyException'".  I am compiling the system
with g++ (on Linux and OSX); I haven't tried MSVC++.
> 
> Is there something that I need to do to get this behaviour to work?  I
admit that I have only a fairly basic understanding of how exception handling is
implemented in C++ but from what I've read it seems like the exception
should unwind through what is, for all intents and purposes, a simple call
stack...
There was an example program detailing how to do exactly this on the
wiki. Was the wiki content archived before it was taken down?

On Thu, Jul 21, 2011 at 03:56:21PM -0600, Geoff Reedy
said
> On Tue, Jul 12, 2011 at 07:25:16PM -0400, Peter Zion said
> > Hi All,
> > 
> > I'm trying to catch an exception that is "passed
through" an LLVM ExecutionEngine but I am unable to do so.  Specifically,
in C++ code, inside a try/catch block, I call a JITted function, which in turn
calls back into my code.  Everything works fine unless an exception is thrown; I
would except the outermost try/catch(...) block to catch the exception thrown in
my innermost C++ code, but instead I get the abort "terminate called after
throwing an instance of 'MyException'".  I am compiling the system
with g++ (on Linux and OSX); I haven't tried MSVC++.
> > 
> > Is there something that I need to do to get this behaviour to work?  I
admit that I have only a fairly basic understanding of how exception handling is
implemented in C++ but from what I've read it seems like the exception
should unwind through what is, for all intents and purposes, a simple call
stack...
> 
> There was an example program detailing how to do exactly this on the
> wiki. Was the wiki content archived before it was taken down?
Actually, I see that the example code I was thinking of is in
examples/ExceptionDemo/ExceptionDemo.cpp of the LLVM source
distribution. The wiki page, as I recall, had some additional exposition
that's not in the source file.

Although I did not archive the wiki entry, the code is at
llvm/examples/ExceptionDemo/ExceptionDemo.cpp and is built (for OS X and Linux)
by building llvm with the environment var BUILD_EXAMPLES set to 1.

Garrison

On Jul 21, 2011, at 17:56, Geoff Reedy wrote:
> On Tue, Jul 12, 2011 at 07:25:16PM -0400, Peter Zion said
>> Hi All,
>> 
>> I'm trying to catch an exception that is "passed through"
an LLVM ExecutionEngine but I am unable to do so.  Specifically, in C++ code,
inside a try/catch block, I call a JITted function, which in turn calls back
into my code.  Everything works fine unless an exception is thrown; I would
except the outermost try/catch(...) block to catch the exception thrown in my
innermost C++ code, but instead I get the abort "terminate called after
throwing an instance of 'MyException'".  I am compiling the system
with g++ (on Linux and OSX); I haven't tried MSVC++.
>> 
>> Is there something that I need to do to get this behaviour to work?  I
admit that I have only a fairly basic understanding of how exception handling is
implemented in C++ but from what I've read it seems like the exception
should unwind through what is, for all intents and purposes, a simple call
stack...
> 
> There was an example program detailing how to do exactly this on the
> wiki. Was the wiki content archived before it was taken down?
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev