Re: [boost] Half-baked GIL IO extension review

Subject: Re: [boost] Half-baked GIL IO extension review
From: Edd Dawson (lists_at_[hidden])
Date: 2010-12-06 20:43:43

On 12/7/2010 12:47 AM, Emil Dotchevski wrote:
>> On 12/6/2010 11:45 PM, Emil Dotchevski wrote:
>>> Did you use -fexceptions with GCC, and if I'm not mistaken MSVC also
>>> has an option to assume that C functions don't throw exceptions, which
>>> shouldn't be used for exceptions to work.
>>
>> I suspect that -fexceptions was not in play but it's conceivable that our
>> build system adds it automatically when compiling C. I'll double check when
>> I'm at work tomorrow.
>
> If I'm not mistaken, the default for GCC is to assume C functions
> can't emit exceptions, -fexceptions tells it that they could. A few C
> libs seem to be compatible with this setup, for example with libpng I
> register an error callback function which throws, and it works fine
> but only if -fexceptions is used.

Ah I see.

Well, my libraries are configurable at build time to allow that. In the JPEG 
case for example, defining either JPEGXX_C_LIB_COMPILED_AS_CPLUSPLUS or 
JPEGXX_CAN_THROW_EXCEPTIONS_THROUGH_C_LIB will allow exceptions to propagate 
undisturbed.

Would it be appropriate to do something similar in the GIL I/O extension? FWIW, 
I'd like to see it.

Kind regards,

Edd