iostream changes locale to format a number

[Paolo Carlini]

Stephen M.Webb wrote:

>I can't spot anywhere in the trunk code where this is done 
>improperly.  I'll set up a test case and see if (a) it's still 
>happening and (b) isolate the cause.
>
The culprit for Takeshi testcase is __convert_from_v in 
locale_facets.tcc but there are more instances of the problematic 
pattern around. It seems to me quite obvious that we are not doing this 
kind of thing in the appropriate way, as explained in glibc2.2.5 docs, 
that is.

Ciao,
Paolo.