I noticed that some sketches does not tun on older IDE, but they can run on newer version IDE and some sketches does not run on newer version IDE, but they can run on older version.
Question: what should I do if I want to use 2 sketches (new and old) together, how do I make it?
Fix the old sketch so it compiles on 1.6.x IDE (I think 1.6.5r5 is the best recent version - they broke some stuff in 1.6.6).
The usual problem is when you've put stuff in PROGMEM, but not declared the variable const. The new version of avr-gcc doesn't like that.
If you have code that's not working on 1.6.x and need help converting it, you could start a thread on it over in programming section - be sure to post the full text of the errors as well as all of the code (using code tags so it's readable)
Just tried both 1.6.6 release and 1.6.7 nightly and can confirm there still appears to be issues under win 7 x64 especially for those that may also want to use ESP boards.
Both still keep offering library updates in a circular path and 1.6.7 also still has the
" 'whateveritlikes' was not declared in this scope " error messages for previously known good sketches
I agree stay with 1.6.5 or 1.6.4 for the moment.
Nick2012Future:
I noticed that some sketches does not tun on older IDE, but they can run on newer version IDE and some sketches does not run on newer version IDE, but they can run on an older version.
There's three major milestones in the IDE / Arduino Library's development:
When I say "break" I just mean that hitting compile fails. Sometimes it is a simple change "replace WProgram.h with Arduino.h" or sometimes it requires more extensive edits. There is a lot of variability in there.
Nick2012Future:
Question: what should I do if I want to use 2 sketches (new and old) together, how do I make it?
You can have multiple versions of the IDE installed. If you're going to be combining code from two separate programs together, it'll require you to rework things anyway.