Re: [ft-devel] freetype, undefined behaviour, and clang

[Sean McBride]

On Sun, 27 Nov 2011 16:04:08 +0900, suzuki toshiya said:

>I built gcc-4.6.1 and clang/llvm-2.9 by myself. It can make working
>binary for the simplest programs, like hello-world, but "apinames"
>built with "-ftrapv" by my clang aborts with "Illegal instruction" error.
>It seems that I have to learn more to make usable clang by myself...

suzuki-san,

The "Illegal instruction" abort is *correct* behaviour when using 
-fcatch-undefined-behavior and -ftrapv.  If you see an "Illegal instruction", 
it means clang has detected the use of some undefined behaviour in your code.  
These are the problems I'd like to see fixed in freetype.

This is explained in detail here:

<http://blog.llvm.org/2011/05/what-every-c-programmer-should-know.html>
<http://blog.llvm.org/2011/05/what-every-c-programmer-should-know_14.html>
<http://blog.llvm.org/2011/05/what-every-c-programmer-should-know_21.html>

Cheers,

--
____________________________________________________________
Sean McBride, B. Eng                 address@hidden
Rogue Research                        www.rogue-research.com
Mac Software Developer              Montréal, Québec, Canada