returnByReference
ftp://ftp.de.debian.org/debian/pool/main/q/qxmpp/qxmpp_1.14.1.orig.tar.gz
2.21.0 qxmpp-v1.14.1-847c24dbd88670a34a2b5c79d7d14b7741c5f710/src/base/QXmppPacket_p.h:24:16: performance: Function 'data()' should return member 'm_data' by const reference. [returnByReference]
ftp://ftp.de.debian.org/debian/pool/main/r/recastnavigation/recastnavigation_1.6.0+dfsg.orig.tar.gz
2.21.0 recastnavigation-1.6.0/Tests/Contrib/catch2/catch_all.hpp:1018:19: performance: Function 'getMessage()' should return member 'message' by const reference. [returnByReference]
2.21.0 recastnavigation-1.6.0/Tests/Contrib/catch2/catch_all.hpp:9029:19: performance: Function 'trimmedName()' should return member 'm_trimmed_name' by const reference. [returnByReference]