[Solved] QMake and optimization flags for compiler

[herophuong]

I'm using Qt Creator and find out that in default, g++ will use -O2 for compiling phase and -O1 for linking phase. I have add -O3 to both QMAKE_CXXFLAGS and LIBS but end up with there both -O3 -O2 in compiling phase and -O1 -O3 in linking phase. Is there a way to control the optimization flags in .pro files?

[lgeyer]

@
QMAKE_CXXFLAGS_RELEASE -= -O2
QMAKE_CXXFLAGS_RELEASE += -O3

QMAKE_LFLAGS_RELEASE -= -O1
@
Make sure you've re-run qmake after modifying your .pro file.

[herophuong]

Oh. I never thought of "-=" operator. Thank you very much.