On 20 November 2014 13:09, Liviu Ionescu <i...@livius.net> wrote: > > On 20 Nov 2014, at 14:50, Peter Maydell <peter.mayd...@linaro.org> wrote: > >> Same thing as if you start a hardware board with nothing loaded >> into the flash. (Probably this means "go into an infinite loop >> of taking exceptions".) > > hmmm... and you consider this behaviour to meet the user-friendly > requirements? > > I tried it, and the program simply hangs, without any stdout/stderr messages.
Yes. That's what hardware does in that situation. I don't think that whether or not a debugger has been connected should change our behaviour. (And even with your patch, if you connect a debugger and just hit its 'run' button without loading an image then we'll do the same exception-loop.) > if you find this behaviour acceptable for unix users, ok, you don't > have to update the other profiles, but for most cortex-m users it is > confusing, and user-friendliness is not only appreciated, but required. I agree it's not very user friendly. But I don't like inconsistency between our behaviour for different boards either. (And for some boards we're going to have a bios or other firmware which will run if you don't specify -kernel.) In general I think many of the concerns you're raising here are real problems, and our user-friendliness is indeed poor in a lot of places. However the solutions you're proposing are often specific to M-profile ARM, whereas I have to consider the whole project and would prefer solutions which clean up and deal with an issue for all boards and all CPUs. That's obviously harder than a more local and restricted fix, but the benefit is greater. thanks -- PMM