why fiasco use -fno-rtti compile option?

Adam Lackorzynski adam at os.inf.tu-dresden.de
Thu Jun 25 22:11:38 CEST 2015


On Fri Jun 19, 2015 at 10:28:47 +0800, liu.xiaodong2 at zte.com.cn wrote:
> 	I want to use typeid() and dynamic_cast() in fiasco, but failed, because of the -fno-rtti option. Why fiasco disable rtti? Are there some bad effects if we enable it?

The first effect are a lot of undefined references when linking. Those
references point to libsupc++ which in turn has only a few dependencies
to libc. Besides adding the lib there are also runtime costs I suppose
which one wants to avoid (or at least know exactly where they are).
Overall it is not necessary to require this functionality, at least for
us.



Adam
-- 
Adam                 adam at os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/



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