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

Mark Mitchell mark@codesourcery.com
Fri Jan 21 01:30:00 GMT 2005


I think it's a mistake to add these explicit initializations on 
platforms that do not actually require it.  Copying uninitialized data 
may be undefined in ISO C++, but on most systems it's well-defined: 
whatever bits happened to be there get copied.  All you're accomplishing 
is making the library slower.

On some systems (IA64) you can get traps on accessing registers with the 
NaT bit set, but on most others, there is no issue.  I can see an 
argument for performing these default initializations in debugging mode, 
or with a flag set by the user, by the default behavior ought to be to 
go as fast as possible.

-- 
Mark Mitchell
CodeSourcery, LLC
mark@codesourcery.com
(916) 791-8304



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