id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
7379,Boost Format strings causing memory leaks,Jason Vincent <jason.vincent@…>,"James E. King, III","I determined that certain format string used in a boost::wformat object will leak memory.  I was using a formatter to convert a value to a floating point value with and without a percent symbol at the end.

The two format strings I was using were:


{{{
L""%1$.1f""
}}}
 - format with one decimal place of precision[[BR]]

{{{
L""%1$.0f %%""
}}}
 - format with no decimal places but add a percent sign

I determined that removing the ""%%"" reduced some of the memory leaks, and removing the ""$.1f"" or ""$.0f"" eliminated the remaining memory leaks.

This was done using Boost v 1.44 with Visual Studio 2010 on Win 7 64-bit.


For more context here is part of the code that I can share:

note, mFormatter is a boost::wformat member object


{{{
MyObject::MyObject() :
    mNumDecimalPlaces   (1),
    mFormatter          (L""%1$.1f"")  //--- THIS LEAKED
{
}


std::wstring MyObject::PercentToString(const FLOAT iMin,
                                       const FLOAT iMax,
                                       const FLOAT iPercent)
{
    FLOAT value = PercentToValue(iMin, iMax, iPercent);

    return boost::str(mFormatter % value); //--- THIS LEAKED
}
}}}
",Bugs,closed,Boost 1.66.0,format,Boost 1.44.0,Problem,worksforme,format memory leak,