I have installed the following qca packages for qca under Ubuntu 15.04:

Qt Code: 
  1. qca2-utils       
  2.   qca-qt5-2-utils
  3.   libqca2                    
  4.   libqca2-plugin-cyrus-sasl  
  5.   libqca2-plugins            
  6.   libqca-qt5-2-dev
  7.   libqca2-dbg                
  8.   libqca2-plugin-gnupg       
  9.   libqca-qt5-2               
  10.   libqca-qt5-2-plugins
  11.   libqca2-dev                
  12.   libqca2-plugin-ossl        
  13.   libqca-qt5-2-dbg
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When running the command dpkg -L libqca2 I get the following:

Qt Code: 
  1. /usr
  2. /usr/lib
  3. /usr/lib/x86_64-linux-gnu
  4. /usr/lib/x86_64-linux-gnu/libqca.so.2.1.0
  5. /usr/share
  6. /usr/share/doc
  7. /usr/share/doc/libqca2
  8. /usr/share/doc/libqca2/copyright
  9. /usr/share/doc/libqca2/changelog.Debian.gz
  10. /usr/lib/x86_64-linux-gnu/libqca.so.2
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The .pro file contains the entry:

Qt Code: 
  1. CONFIG += c++11 crypto
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and in the main.cpp I have:

Qt Code: 
  1. #include <Qca-qt5/QtCrypto/QtCrypto>
  2.  #include <QtCrypto/QtCrypto>
  3.  
  4.  int main(int argc, char *argv[]) {
  5.  
  6.          QCA::Initializer init;
  7.  
  8.          return 0;
  9.   }
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But I get the error

Qt Code: 
  1. /main.cpp:37: error: undefined reference to `QCA::Initializer::Initializer(QCA::MemoryMode, int)'
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Is there anything else I need to install or add in the .pro file?