From: moreno_news@mailinator.com   
      
   On 11-11-09 03:58 PM, Pete Becker wrote:   
      
   > [ ... ] In the original example (no   
   > inheritance, no virtual functions involved) there's no good reason for   
   > a compiler to generate code that does unexpected things.   
      
   Huh???   (care to elaborate on how exactly you define "unexpected"   
   in the above sentence??  :-) )   
      
   What do you mean "no good reason"???  You don't find the fact that   
   this *is not allowed to be NULL* reason enough for the compiler to   
   optimize away that if, thus guaranteeing that the program will   
   crash ???   
      
   True, the examples given by the previous poster did not really   
   address the this pointer, and it was mainly situations where   
   the sequence of executed statements is what hints the compiler   
   about "impossibility" of a pointer being NULL.   But still, if   
   indeed (or I should say, *given that* indeed) the this pointer   
   *is not allowed* to take the NULL value, then it seems perfectly   
   reasonable for the compiler to replace if (this == NULL) with   
   if (false), including entirely removing the corresponding block   
   associated to that if.   
      
   Am I missing something??   
      
   Carlos   
   --   
   PS:  Notice that, from the point of view of my original post,   
         the argument by the previous poster is not completely   
         useful, in that I was trying to convince someone that   
         allowing a situation where this == NULL is not legal;   
         the argument by the previous poster goes more along the   
         lines of presenting an example that shows why that   
         particular instance of UB *can* have consequences in   
         real-life situations.  (but if the person is not convinced   
         that it *is* UB, then the example would tell him nothing.   
         Just a remark --- I highly appreciated the example!!)   
      
      
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         [ comp.lang.c++.moderated.    First time posters: Do this! ]   
      
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