valgrind error message
Very often, Valgrind gives this kind of message: ==11111== Use of uninitialised value of size 4 ==11111== at 0x5FE398C: std::string::_Rep::_M_clone(std::allocator const&, unsigned int) (in /usr/lib/libstdc++.so.6.0.13) ==11111== by 0x5FE47AC: std::string::reserve(unsigned int) (in /usr/lib/libstdc++.so.6.0.13) ==11111== by 0x5FE4A1A: std::string::append(char const*, unsigned int) (in /usr/lib/libstdc++.so.6.0.13) ==11111== by 0x5FE4AE4: std::string::append(char const*) (in /usr/lib/libstdc++.so.6.0.13) ==11111== by 0x806AEE8: std::basic_string<char, std::char_traits, std::allocator > std::operator+<char, std::char_traits, std::allocator >(std::basic_string<char, std::char_traits, std::allocator > const&, char const*) (basic_string.h:2112) ==11111== by 0x4203648: mio::IOException::IOException(std::string const&, std::string const&) (IOExceptions.cc:41) ==11111== by 0x806E3E6: mio::UnknownValueException::UnknownValueException(std::string const&, std::string const&) (IOExceptions.h:150) ==11111== by 0x8070286: void mio::IOUtils::getValueForKeystd::string(std::map<std::string, std::string, std::lessstd::string, std::allo cator<std::pair<std::string const, std::string> > > const&, std::string const&, std::string&, unsigned int const&) (IOUtils.h:253) ==11111== by 0x8071E01: void mio::Config::getValuestd::string(std::string const&, std::string const&, std::string&, mio::Config::Options const&) const (Config.h:239) ==11111== by 0x4095178: SnowpackConfig::SnowpackConfig(std::string const&) (SnowpackConfig.cc:119) ==11111== by 0x805E139: main (Main.cc:670) ==11111== Uninitialised value was created by a heap allocation ==11111== at 0x4023F7E: malloc (vg_replace_malloc.c:236) ==11111== by 0x61687A1: backtrace_symbols (backtracesyms.c:72) ==11111== by 0x42035BA: mio::IOException::IOException(std::string const&, std::string const&) (IOExceptions.cc:38) ==11111== by 0x806E3E6: mio::UnknownValueException::UnknownValueException(std::string const&, std::string const&) (IOExceptions.h:150) ==11111== by 0x8070286: void mio::IOUtils::getValueForKeystd::string(std::map<std::string, std::string, std::lessstd::string, std::allo cator<std::pair<std::string const, std::string> > > const&, std::string const&, std::string&, unsigned int const&) (IOUtils.h:253) ==11111== by 0x8071E01: void mio::Config::getValuestd::string(std::string const&, std::string const&, std::string&, mio::Config::Options const&) const (Config.h:239) ==11111== by 0x4095178: SnowpackConfig::SnowpackConfig(std::string const&) (SnowpackConfig.cc:119) ==11111== by 0x805E139: main (Main.cc:670)