halt with optional message?

[Vladimir Panteleev]

On Thu, 11 Aug 2011 14:20:46 +0300, bearophile <bearophileHUGS at lycos.com>  
wrote:

> Contracts contain asserts,

But contracts are removed in release executables too, no?

> sometimes asserts are kept in the released binaries too (dmd has many  
> asserts active) and those asserts hopefully contain an error message for  
> debugging.

Consider: regular asserts are removed from release executables. assert(0)  
compiles to a HLT instead of nothing merely because it has practically no  
overhead (only one byte of machine code)!

I think you're confusing the purpose of asserts with something else again.  
Besides, there are some who think that the special case of assert(0) is  
confusing/inconsistent with regular asserts enough, why do you want to  
enlarge that distinction even more?

> I don't think that removing them improves the program and its usage in  
> any way.

If I'm writing a commercial, closed-source program meant for  
redistribution, including any unnecessary information that helps reversers  
to understand how the program works is just stupid.

> Also, here we are discussing about assert(0), it's a different kind of  
> assert, that is kept in release mode too. If the program prints a  
> debugging message and the user tells me the error message (this is right  
> what has just happened to me), I am able to know what assert(0) has  
> fired even if the user is not using a debugger. So I don't think you are  
> right.

You're not supposed to use -release if you want to know what happened.  
Failed asserts in release executables should never happen, unless your  
program is buggy. If your program is buggy, don't use -release until  
you've debugged it.

> puts() is not pure, so if you add a puts() in a function, the function  
> can't be pure. So the function that calls this function can't be pure...

This is the least of my concern.

-- 
Best regards,
  Vladimir                            mailto:vladimir at thecybershadow.net