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From: Thiago Adams <thiago.adams@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: dbg_break macro
Date: Thu, 6 Jun 2024 17:40:30 -0300
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On 06/06/2024 17:10, Blue-Maned_Hawk wrote:
> 
> I feel like you would probably want to be using a debugger to set your
> breakpoints, although the Clang dialect of C does have a
> __builtin_debugtrap builtin subroutine.
> 
> 
> 


C++ 26 will have breakpoint. Lot of links about how to do that.
https://en.cppreference.com/w/cpp/utility/breakpoint

But, thinking about my usage, the source line, message, etc., everything 
that assert has is useful. What is not useful is to pass a constant 
expression for something that is supposed to be a runtime check.

I remember when I thought that static_assert could just be assert 
because it is not hard for the compiler to know when we have a constant 
expression or not. If we have a constant expression, this should be just 
like static_assert.

assert(2 == 2); // compile-time check

If the expression is not constant, then it would be checked at runtime 
during debugging.

This idea fails fast, when we think assert is used with assert(0);

This code would not compile.

if (condition)
{
   ///
}
else{
   assert(0);
   return -1;
}


So, my idea with dbg_break is to reserve assert for what it does better, 
that is runtime checks.

Another sample

int f(int v){
  switch(v)
  {
     case 1:break;
     case 2:break;
     default:
      assert(0);
      break;
  }
}

This code does not have a plan B in case default is reached.

But this one have.

int f(int v){
  switch(v)
  {
     case 1:break;
     case 2:break;
     default:
       dbg_break("missing case ?");
      break;
  }
  return -1;
}

I think dbg_break also transmit the idea that the branch is possible 
while assert(0) can be confusing.