Nick
Thanks for the links. Seems I'm on a well traveled road! I have just boosted the bug report.
My time has not been wasted since I was new to C, Arduino, Gobetwino, etc, and the process of digging around for code to expose the issue has helped me learn a lot, BUT... (This is not a rant, even if it reads like one!!).
I find the overall experience puzzling, and worrying. There is a known serious bug right at the heart of the project, the DMA. And we know apparently that Strings use DMA. I'll try an analogy: for Arduino brand=Ford, Arduino board=Car, Strings=automatic gearbox, DMA=cogwheel, Arduino Reference page= Showroom, SRAM=oil.
Ford sell cars. There are numerous reports of problems with their automatic gearboxes. They are traced to defective cogwheels. The cars occasionally crash. Various customers chat amongst themselves and suggest that perhaps automatics aren't such a great idea, they're a bit expensive on oil, etc. Most are oblivious to the true danger within. Ford continues to advertise the automatic feature in their showroom, telling you exactly how it works.
Now someone finds out the the same cogwheels are used throughout the car. The problem gets put on some engineer's todo list and gets a medium priority!!!! OMG. Meanwhile customers around the country are puzzled as to why their cars keep crashing. Most mechanics tell them to check the oil.
There are always bugs, but this is a doozer. It's the fact that the DMA free list is at the heart of of things that worries me most. Microcontrolers control real things that can be dangerous, in my case a kiln. The doubts are surfacing ... Is this a genuine development environment, or just a hobby playground? Is Arduino a trustworthy babysitter for my kiln?
If I can put some limits in the next few hours on the where Strings go amiss, I'll post the results. Then back to my project to sanitize it.
Please do what you can to get the Reference pages changed. Without specific knowledge of where Strings do and dont work, Strings are a complete liability and IMHO should not be offered up as a working feature by appearing there. Same applies to DMA, but at least that's not on the first page you read !! (Should Arduino library developers be warned?)
What about a specific place on the Playground/Forum for known bugs, and how to avoid them? I'd read it. Not everything on the bug list of course, but serious bugs likely to trip up the average user.
And while we're at it, what about a specific place on the Playground/Forum for known C poo-traps for the uninitiated, and how to avoid them? I'd read it, and it might seriously cut down on repetitive Forum traffic.
Enough already. Cheers.