[PATCH] Fix PR libstdc++/19510: Uninitialized variable in some iterators

[Mark Mitchell]

Gabriel Dos Reis wrote:

> In the typical case where a singular iterator is created, it is
> inlined and if the compiler cannot figure out that those inlined
> initialization can be efficiently turned into something else, then
> it is a compiler bug.

I'm not confident that the compiler will always be able to figure this out.

In any case, why should we take that chance?

If someone runs a benchmark of G++ & V3 vis a vis some other system, and 
the benchmark shows that we're slower, we lose.  It doesn't matter 
whether that's because of the compiler or the library.  No, I'm not 
arguing that we should hand code the entire library in some special 
style that's particularly amenable to G++.  I am arguing, however, that 
inserting code to do something that is on most systems at best 
pointless, and quite possibly harmful, is a mistake.

-- 
Mark Mitchell
CodeSourcery, LLC
mark@codesourcery.com
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