Re: [avr-gcc-list] [Bug target/35634] New: [avr] result of char promotion comes out of CHAR_MIN/MAX

[Rolf Ebert]

Dave N6NZ schrieb:
> Dmitry K. wrote:
> > Now I can not understand, why the Standart permits
> > 'undefined behavior' with ordinary overflow,
>
> Well, checking for integer overflow can cause a lot of code to be 
> generated on some architectures.  That becomes both a space and 
> performance issue.  In general, the C standard favors fast and small 
> over tightly defined results.
>
> You might like Ada :)
> Just kidding.

Due to the poor code that gcc generates for detecting overflow (on all 
platforms), overflow detection is swithced off by default in gcc-Ada. 
You really have to insist and know about the -gnato option to get a 
standard conforming Ada compiler.

For not getting completely off topic on the avr-gcc mailing list let me 
point out that integer overflow is signaled by an exception in Ada and 
exceptions are not (yet) supported in AVR-Ada.

  Rolf