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POvalgrind reports uninitialised value in BSONObj::toString with a simple BSON object created with GENOID
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14186246
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2013-01-06T20:11:09.170
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2013-01-07T19:51:48.940
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Using valgrind on a very simple example from the C++ driver of mongodb, it appears that something is wrong as soon as we use GENOID explicitly in the definition of a BSONObj. Here is an example that illustrates the problem: (tested on gcc 4.4.5, boost 1.42, debian 6, mongodb C++ driver 2.2) <pre><code>#include <cstdio> #include <string> #include "mongo/db/jsobj.h" main() { mongo::BSONObj p = BSON( mongo::GENOID << "name" << "Joe" << "age" << 33 ); std::string s = p.toString(); std::cout << s; } </code></pre> When run with valgrind, we get this message: <pre><code>==2506== Use of uninitialised value of size 8 ==2506== at 0x40A66B: mongo::toHexLower(void const*, int) (hex.h:64) ==2506== by 0x40A73F: mongo::OID::str() const (oid.h:66) ==2506== by 0x40A798: mongo::operator<<(mongo::StringBuilderImpl<mongo::TrivialAllocator>&, mongo::OID const&) (oid.h:140) ==2506== by 0x40DCC1: mongo::BSONElement::toString(mongo::StringBuilderImpl<mongo::TrivialAllocator>&, bool, bool, int) const (bson-inl.h:765) ==2506== by 0x40C898: mongo::BSONObj::toString(mongo::StringBuilderImpl<mongo::TrivialAllocator>&, bool, bool, int) const (bson-inl.h:475) ==2506== by 0x40C5A5: mongo::BSONObj::toString(bool, bool) const (bson-inl.h:445) ==2506== by 0x40A1B8: main (mongobug.cc:10) </code></pre> If I remove the GENOID from the BSONObj definition, the problem is gone. This is a minimalist version of a more complex but similar problem I have when I use mongo::OID::gen() in my project. The example above is taken from the official mongodb C++ driver tutorial here: <a href="http://www.mongodb.org/pages/viewpage.action?pageId=133415#C%2B%2BTutorial-BSON" rel="nofollow">http://www.mongodb.org/pages/viewpage.action?pageId=133415#C%2B%2BTutorial-BSON</a> Any idea what could be wrong? Thanks,
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<c++><mongodb><bson>
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valgrind reports uninitialised value in BSONObj::toString with a simple BSON object created with GENOID
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