https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53637
marc at kdab dot com changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |marc at kdab dot com --- Comment #1 from marc at kdab dot com --- Similar situation in https://codereview.qt-project.org/#/c/104079/1/src/network/ssl/qsslellipticcurve_openssl.cpp,unified (click on the comment in line 61 to see GCC 4.9.3 (from svn) disassembly. Qt is full of functions structured like that and it's not an option to rewrite them all. Lawrence Crowl calls (N)RVO the most important optimisation in C++, and it's really sad that GCC doesn't apply NRVO even in those cases where there is only one possible object returned per basic block, ie. where the compiler knows which object will be returned by at the time of construction of each object. It's even more sad that this report has been sitting here, unconfirmed and ignored by the GCC developers, for 19 months.