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From: David Brown <david@westcontrol.com>
Subject: Re: Compiler message -Wunused confusion
Date: Wed, 14 Feb 2024 13:44:45 +0100
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On 14/02/2024 12:11, A. Mc. via Gcc-help wrote:
> Hello,
> 
> I am receiving the gcc compiler warning -Wunused-value computed not used. I
> can confirm this is true in my embedded application, the statement never
> switches. But I am completely confused as to why. It's essentially the
> following code:
> 
> volatile bool foo;
> 
> while (true) {
> if (foo == true){
>         //do something
>         foo = false;}
> else{
>         //do something else
>         foo = true;}
> }
> 
> Which never switches. What could be the cause of this?
> 
> Many thanks in advance!
> 

My guess is that you have simplified the code a bit too much here. 
Something else is wrong.  (It is a good idea to pare down the code to 
the minimum that demonstrates the problem, as you have tried to do here. 
  But I think you have removed to much!)

David