Re: [Boost-users] Subject: Serialization, text_Xarchive Why doesn't work?

From: Robert Ramey (ramey_at_[hidden])
Date: 2006-08-03 11:14:41

Is it possible that m_value is uninitialized?  It is a known
problem that many compilers can can write uninitialized
floating/double values to a text stream and then cannot
read them.  This topic is currently being discussd on
the developer's list - as it arises all the time.

Take a look a test_serial.txt with a text editor.
What does it look like?

Robert Ramey

tkachenkok_at_[hidden] wrote:
> I've tried to write my first application with Boost.Serialization
> library.
>
> Here is the part of code, where the boost::text_iarchive throws an
> exception "boost::archive::archive_exception" "what():  stream
> error":
>
> [code]
> enum Origin {
>     UNKNOWN=0,
>     MEASURED,
>     AVERAGE };
>
> class OTCValue
> {
> friend class boost::serialization::access;
> template<class Archive>
> void serialize(Archive & ar, const unsigned int version)
> {
> ar & m_value;
> ar & m_orig;
> }
> double m_value;
> Origin m_orig;
>         ...
> };
>          ...
> const OTCValue val1=(*loaded.second.begin())->get_row(0)[0];
> {
> std::ofstream ofs("test_serial.txt");
> boost::archive::text_oarchive oa(ofs);
> oa << val1;
> }
> OTCValue val;
> {
> std::ifstream ifs("test_serial.txt");
> boost::archive::text_iarchive ia(ifs);
> ia >> val; // here is this exceptions thrown
> }
>         ...
> [/code]
>
> And here is a little bit different code, which works great:
>
> [code]
> enum Origin {
>     UNKNOWN=0,
>     MEASURED,
>     AVERAGE };
>
> class OTCValue
> {
> friend class boost::serialization::access;
> template<class Archive>
> void serialize(Archive & ar, const unsigned int version)
> {
> ar & m_value;
> ar & m_orig;
> }
> double m_value;
> Origin m_orig;
>         ...
> };
>          ...
> const OTCValue val1(5.5, MEASURED);
> {
> std::ofstream ofs("test_serial.txt");
> boost::archive::text_oarchive oa(ofs);
> oa << val1;
> }
> OTCValue val;
> {
> std::ifstream ifs("test_serial.txt");
> boost::archive::text_iarchive ia(ifs);
> ia >> val;
> }
>         ...
> [/code]
>
> What is the problem? The construction
> (*loaded.second.begin())->get_row(0)[0] returns an OTCValue .
>
> I have compiled the boost-1.33.1 from the sources (www.boost.org).
> The project I've made is under KDevelop 3.2.2 (initially consol
> "Hello World" application)
>
> Operating System: SuSe Linux 10.0
> Compiler: gcc version 4.0.2
>
> I hope, that I've gave enouph information. If not, ask what aou need,
> you are welcome.
>
> Best regards,
> and thanks to all!