[fpc-devel] Status of SEH in FPC

[Sergei Gorelkin]

03.03.2013 2:53, Flávio Etrusco пишет:
> Hello,
>
> what's the current state of the SEH in FPC trunk?
> IIRC - and according to wikipedia ;-) - SEH, at least for Windows, was
> in the 2.7 roadmap, but I can't find any related brach, or commit, or
> post.
> Also AFAIU would have some gains in both executable size and speed, correct?
>
By now SEH is fully implemented for Win64 target, but you need to cycle the compiler with 
OPT=-dTEST_WIN64_SEH to enable it.
The most of it was committed in revision 20098.

The effect of SEH is two-fold: it gives some performance gain when running without exceptions, but 
big penalty when exceptions occur. It somewhat reduces code size but at the same time adds some 
data, so executable size may not reduce.

The main advantage of SEH is the conformance with OS exception handing scheme. Without it, it was 
almost impossible to use DLLs that raise exceptions.

Regards,
Sergei