Sequence points

[Dave Theese]

Hello all,

I have read the definition of a sequence point in the standard and can
follow it mechanically, but for some reason, I'm having a hard time grasping
the conceptual meaning and significance. Can someone out there offer good
intuition on sequence points???

Thank you!
Dave

 

[Alf P. Steinbach]

I have read the definition of a sequence point in the standard and can
follow it mechanically, but for some reason, I'm having a hard time grasping
the conceptual meaning and significance. Can someone out there offer good
intuition on sequence points???

Goodest intuition: you don't need to think about them if you avoid
expressions with side-effects.

That also generally gives much more clear code.

Leave it to the compiler to do the trivial optimizations.

 

[Karl Heinz Buchegger]

Hello all,

I have read the definition of a sequence point in the standard and can
follow it mechanically, but for some reason, I'm having a hard time grasping
the conceptual meaning and significance. Can someone out there offer good
intuition on sequence points???

Sequence points are a somewhat artificial concept. Basically a sequencepoint
is a spot in processing where you can be sure that every computation has finished
and the results are where they should be. Between 2 sequencepoints the compiler
is free to rearrange things any way it pleases him. So you cant relay on anything.
Only after a sequencepoint is passed, it is safe to expect results where they
should be.