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Re: Arduino / compilers on uC

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From	David Brown <david.brown@hesbynett.no>
Newsgroups	sci.electronics.design
Subject	Re: Arduino / compilers on uC
Date	Tue, 07 Feb 2017 12:58:39 +0100
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On 07/02/17 12:26, Tom Gardner wrote:
> On 07/02/17 10:52, rickman wrote:
>> On 2/7/2017 4:40 AM, Tom Gardner wrote:
>>> On 07/02/17 09:01, rickman wrote:
>>>> On 2/7/2017 3:07 AM, Tom Gardner wrote:
>>>>> On 07/02/17 02:47, dagmargoodboat@yahoo.com wrote:
>>>>>> Don't underestimate people.  Everyone I know got started writing
>>>>>> assembly,
>>>>>> or worse, toggling front panel switches.
>>>>>
>>>>> From what I can make out, precisely nobody does that now.
>>>>>
>>>>> Hell's teeth, even *30* years ago too many didn't have
>>>>> a clue about what a compiler emitted. I had a standard
>>>>> interview question: given
>>>>>   int foo;
>>>>>   float baz;
>>>>>   char bat = foo(baz, bar);
>>>>> what *kind* of instructions would you expect a processor
>>>>> to execute. Too many couldn't describe push/jsr/pop
>>>>> instructions.
>>>>
>>>> I would have a hard time describing the call sequence when foo is
>>>> declared as an
>>>> integer and used as a function.  ???  Was that supposed to be int
>>>> bar; ?
>>>
>>> There are two responses I can give:
>>>  1) I would expect a candidate to comment on those flaws
>>>  2) oh, picky picky picky
>>>
>>> I'm not going to say which is more appropriate :)
>>
>> In an interview once I was asked how many multipliers were used in a CIC
>> filter.  I had to think for a moment to make myself believe I wasn't
>> messing
>> this up before I said, I didn't know there were any multipliers in
>> one.  I must
>> have had a funny look on my face because the interviewer looked rather
>> sheepish
>> and said, yes, they don't use multipliers, in fact that is the main
>> reason they
>> are used.  I felt I had embarrassed him somehow.  Maybe he didn't have
>> many
>> candidates who didn't screw that one up.
>>
>> As to your example, I find it confusing because there are different
>> ways this
>> could be correct, some requiring more than one error.  But if this was
>> intentional on and interview question I would not put it past an
>> interviewer to
>> do throw multiple mistakes in.
>>
>> I should have said, "There won't be any instructions generated by the
>> compiler."  Then I would just side step the issue of exactly what was
>> wrong with
>> the code perhaps.
> 
> And that would be an interesting response, because it
> hints that a candidate had used an optimising
> compiler in anger, or even just liked to assure themselves
> that they understood what was happening "under the hood".

They don't have to be familiar with optimising compilers (not that there
are many compilers that /don't/ optimise).  They just need to be
familiar with compilers that require valid C code in order to generate
assembly instructions instead of error messages.  The code, as given,
cannot possibly compile - thus no instructions would be generated.

> 
> I could probably have an interesting conversation with
> such a candidate :)
>

Thread

Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 15:43 -0800
  Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-07 10:58 +1100
    Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-06 19:09 -0500
    Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 18:30 -0800
      Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-06 21:43 -0500
        Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 19:02 -0800
          Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-06 23:26 -0500
            Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 21:05 -0800
      Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-07 13:55 +1100
        Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 20:00 -0800
          Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-07 19:31 +1100
          Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-07 10:29 +0100
            Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-07 07:39 -0800
              Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-08 12:24 +0100
                Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-09 08:36 -0800
                Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-10 08:15 +1100
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-13 15:37 +0100
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-13 15:35 +0100
          Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-07 08:05 -0800
            Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-08 12:30 +0100
  Re: Arduino / compilers on uC mrdarrett@gmail.com - 2017-02-06 15:59 -0800
  Re: Arduino / compilers on uC Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-06 16:04 -0800
    Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 18:41 -0800
      Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-07 14:08 +1100
        Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 20:14 -0800
          Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-07 08:00 +0000
            Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-09 05:42 -0800
              Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-09 15:07 +0100
                Re: Arduino / compilers on uC Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-09 09:54 -0800
              Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-09 15:55 +0000
                Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-09 08:46 -0800
                Re: Arduino / compilers on uC Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-09 14:42 -0500
                Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-11 06:54 -0800
                Re: Arduino / compilers on uC pcdhobbs@gmail.com - 2017-02-11 07:31 -0800
                Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-11 07:59 -0800
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-11 17:01 +0000
                Re: Arduino / compilers on uC pcdhobbs@gmail.com - 2017-02-11 12:52 -0800
                Re: Arduino / compilers on uC krw@notreal.com - 2017-02-11 18:46 -0500
                Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-12 10:20 +1100
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-13 16:07 +0100
                Re: Arduino / compilers on uC Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-09 14:16 -0500
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-09 22:39 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-13 16:06 +0100
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-13 15:29 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-13 16:49 +0100
                Re: Arduino / compilers on uC Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-13 10:55 -0500
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-13 17:09 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-14 09:49 +0100
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-13 16:07 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-14 10:01 +0100
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-14 09:49 +0000
                Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-17 04:21 +1100
                Re: Arduino / compilers on uC pcdhobbs@gmail.com - 2017-02-16 14:47 -0800
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-17 00:17 +0000
          Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-07 19:49 +1100
            Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-09 06:22 -0800
          Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-07 10:42 +0100
            Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-09 06:57 -0800
              Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-09 16:12 +0100
              Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-10 08:24 +1100
  Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-06 19:08 -0500
    Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 18:47 -0800
      Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-06 21:51 -0500
        Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 20:39 -0800
          Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 20:55 -0800
            Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-07 20:05 +1100
              Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-08 12:26 -0500
                Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-08 12:32 -0500
                Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-09 08:31 +1100
                Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-09 08:21 +1100
                Re: Arduino / compilers on uC Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-08 13:33 -0800
          Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-07 08:15 +0000
            Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-09 05:51 -0800
              Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-09 16:22 +0000
                Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-09 16:45 -0500
                Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-09 16:51 -0500
                Re: Arduino / compilers on uC Clifford Heath <no.spam@please.net> - 2017-02-10 09:11 +1100
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-09 22:45 +0000
                Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-15 10:11 -0500
          Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-07 10:57 +0100
      Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-07 08:07 +0000
        Re: Arduino / compilers on uC rickman <gnuarm@gmail.com> - 2017-02-07 04:01 -0500
          Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-07 09:40 +0000
            Re: Arduino / compilers on uC rickman <gnuarm@gmail.com> - 2017-02-07 05:52 -0500
              Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-07 11:26 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-07 12:58 +0100
                Re: Arduino / compilers on uC Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-09 14:52 -0500
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-09 22:47 +0000
              Re: Arduino / compilers on uC bitrex <bitrex@de.lete.earthlink.net> - 2017-02-09 14:00 -0500
                Re: Arduino / compilers on uC Tim Wescott <seemywebsite@myfooter.really> - 2017-02-09 13:24 -0600
      Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-07 10:52 +0100
    Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-07 10:50 +0100
  Re: Arduino / compilers on uC rickman <gnuarm@gmail.com> - 2017-02-06 19:49 -0500
  Re: Arduino / compilers on uC "David Eather" <eather@tpg.com.au> - 2017-02-07 12:45 +1000
    Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-06 18:51 -0800
      Re: Arduino / compilers on uC "David Eather" <eather@tpg.com.au> - 2017-02-08 06:35 +1000
        Re: Arduino / compilers on uC "David Eather" <eather@tpg.com.au> - 2017-02-08 06:44 +1000
      Re: Arduino / compilers on uC M Philbrook <jamie_ka1lpa@charter.net> - 2017-02-07 17:11 -0500
        Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-08 12:40 +0100
          Re: Arduino / compilers on uC pcdhobbs@gmail.com - 2017-02-08 07:01 -0800
            Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-08 17:25 +0100
              Re: Arduino / compilers on uC jack4747@gmail.com - 2017-02-09 06:51 -0800
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-09 16:41 +0100
                Re: Arduino / compilers on uC M Philbrook <jamie_ka1lpa@charter.net> - 2017-02-09 19:44 -0500
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-13 16:14 +0100
                Re: Arduino / compilers on uC John Devereux <john@devereux.me.uk> - 2017-02-16 12:57 +0000
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-16 14:11 +0000
                Re: Arduino / compilers on uC John Devereux <john@devereux.me.uk> - 2017-02-16 14:40 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-16 15:58 +0100
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-16 15:56 +0000
                Re: Arduino / compilers on uC John Devereux <john@devereux.me.uk> - 2017-02-16 16:45 +0000
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-16 17:18 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-17 14:59 +0100
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-17 14:24 +0000
                Re: Arduino / compilers on uC Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2017-02-17 21:07 +0200
                Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-17 20:16 +0000
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-17 23:28 +0100
                Re: Arduino / compilers on uC Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-02-17 10:21 -0500
                Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-17 16:34 +0100
                Re: Arduino / compilers on uC M Philbrook <jamie_ka1lpa@charter.net> - 2017-02-09 19:43 -0500
  Re: Arduino / compilers on uC Tim Wescott <tim@seemywebsite.com> - 2017-02-10 10:41 -0600
    Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-11 07:06 -0800
      Re: Arduino / compilers on uC Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-02-11 17:09 +0000
    Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-13 16:28 +0100
  Re: Arduino / compilers on uC Tim Wescott <tim@seemywebsite.com> - 2017-02-14 09:59 -0600
    Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-14 13:46 -0800
      Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-15 10:04 +0100
        Re: Arduino / compilers on uC dagmargoodboat@yahoo.com - 2017-02-15 05:57 -0800
          Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-15 16:02 +0100
            Re: Arduino / compilers on uC David Brown <david.brown@hesbynett.no> - 2017-02-15 17:15 +0100
          Re: Arduino / compilers on uC Tim Wescott <tim@seemywebsite.com> - 2017-02-16 14:19 -0600

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