IBM XL C/C++ NOSTRICT_INDUCTION

[rCs]

I was reading the IBM manual for the IBM XL C/C++ compiler (OK, I'm a
little bored right now) and I found a NOSTRICT_INDUCTION option. The
description partially reads:

Loop induction variable optimizations can change the result of a
program if truncation or sign extension of a loop induction variable
occurs as a result of variable overflow or wrap-around.

Does anyone know if this means that the IBM XL C/C++ performs loop
induction optimization for both signed and unsigned integer values
when the NOSTRICT_INDUCTION compiler option is in effect?

Thanks,
rCs

 

[Richard Bos]

I was reading the IBM manual for the IBM XL C/C++ compiler (OK, I'm a
little bored right now) and I found a NOSTRICT_INDUCTION option. The
description partially reads:

Loop induction variable optimizations can change the result of a
program if truncation or sign extension of a loop induction variable
occurs as a result of variable overflow or wrap-around.

Does anyone know if this means that the IBM XL C/C++ performs loop
induction optimization for both signed and unsigned integer values
when the NOSTRICT_INDUCTION compiler option is in effect?

I don't know whether it performs that optimisation, but that one
sentence, at least, does not imply it - not, that is, for _both_ signed
and unsigned values.

Richard