If the format string have an absolute tabulation (%t), the basic_format::clear() method throws an access violation because of this piece code in format_implementation.hpp(138):<br><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; if( bound_.size()==0 || !bound_[ items_[i].argN_ ] )
<br><br>Here items_[i].argN_ can be negative (defined in internals.hpp(70)), which is an invalid index to bound_[].<br>I think a simple check of greather than zero would suffice to fix it.<br>Here is a code that catches it:
<br><br>using boost::format;<br>format f(&quot;%0s%-32.32s:%|40t|%|.6|%|55t|%25s\n&quot;);<br>f % &quot;test1&quot; % 2.0 % &quot;test3&quot;;<br>f % &quot;test4&quot; % 5.0 % &quot;test6&quot;; // calls clear() and breaks
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