Explanation of QMAKE_CFLAGS_RELEASE and QMAKE_LFLAGS_RELEASE in mkspecs/qmake.conf

[rubikon]

I want to compile Qt 5.0.2 statically with MSVC2010 and I tried to google how to do that.

I've read that I should modify QMAKE_CFLAGS_RELEASE to '-Ol -Og -GL -MD' in the qmake.conf. The original flags are '-O2 -MD'

Somewhere else I read that I have to modify QMAKE_LFLAGS_RELEASE.

So I asked myself what do this flags mean? I wasn't able to find documentation of this macros/flags.

Can someone explain me what this flags mean?

[SGaist]

Hi,

CFLAGS are used at compilation time (by the compiler)
LFLAGS at linking time (by the linker)

The flags themselves are platform dependent

The O flag is for optimization (speed/size etc...)
MD to link against multi-threaded DLL runtime
MT to link multi-threaded static runtime

Hope it helps

[rubikon]

Thank you for your reply. That makes things a little bit clearer...

If the O flag means optimization, what does the number or the second letter stands for? Ol, O2, Og?

And what means the GL flag?

What do I have to edit if I want a static build?

Is there a general description of the flags?

Edit: I think I found it "here":http://msdn.microsoft.com/en-us/library/fwkeyyhe.aspx

Many questions :-)

[SGaist]

Depends on what you mean by static build:

Qt static against dynamic runtime ? (Recommended)
Simply run configure with -static.

If you want Qt static against static runtime you'll have to edit the makespec and change MD to MT (there might be other modifications to do but I don't know them from the top of my head)

IIRC there is something about that in the documentation.