How to build qt out of source

Question

I was searching a lot through Qt forums and Google for the last few days, but I could not find any obvious answer to this question.

I found the -prefix option (not even documented on Windows) that can be supplied to configure to specify different install directory, but this is not clear separation of the sources and binaries at all, since the build is still done in the source directory and then the files needed for installation are copied to the install directoy. I tried this -prefix option, and came to some problems. (i.e It doesn't copy the .pdb files to the install directory.)

Then I found this link about doing shadow builds but it has the big limitation that the build dir must be at the same level as the source dir.

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I'm guessing you didn't try make install? So try that. It should install Qt to a separate directory away from the sources.

Are you saying that after I do configure, I should do nmake install instead just nmake? I know that nmake will process the generated makefiles from qmake and will place them in the source Qt dir, but what nmake install will exactly do i.e in which directory will install the files and how to specify the directory where the files will be installed.

Note that I already do this:

configure -prefix builddir -platform win32-msvc2005
nmake install

The effect of the above two lines was that qt was compiled in the source dir and not directly to my builddir specified with prefix. Then the compiled files were copied in my builddir. I was hoping for something that will build my Qt files directly to the build dir, cause this way I stil need 4 Gb space for my source dir during the compilation. Also the pdb files were not copied to my buildir which is another issue.

Solution

Basically, you just have to run configure.exe from your build directory. For example:

mkdir \qt\4.5.2-build
cd \qt\4.5.2-build
set PATH=%cd%\bin;%PATH%
\qt\4.5.2-sources\configure.exe -platform win32-msvc2005

Where sources are in \qt\4.5.2-sources, that would cause the build to go into \qt\4.5.2-build on the current drive.

Also, you must have perl in your PATH, ActiveState Perl is suggested.

I had not previously heard of this limitation where the build and source directories must be at the same level. If you hit this problem you could try working around it by creating a symbolic link (see mklink command).

Comments

[user152508]

This does not work. The error says that it can't include some .h file

[user152508]

the error is at configure time and it says that it can't include some qscriptengine.h. Also in my try the build directory was not in the same level as the source directory (like in your primer above). Is this relevant?

[user152508]

Here is my folder structure : --X --qt --shadow I want to build in shadow : cd C:/X/shadow C:/X/qt/configure.exe -platform win32-msvc2005421904 I also have shadow/bin and path to perl.exe in my PATH. And Iam still getting the same error at configure time : c:\x\qt\qmake\project.h(57) : fatal error C1083: Cannot open include file: 'qscriptengine.h': No such file or directory

[user152508]

Also note that I am getting the error when configure tries to build qmake.

[user152508]

I can't believe that there is no support from qmake (or maybe am missing something) to do this i.e to build out of source. It is such a common requirement. How suppose to store my qt library on repository now ? ha

[rohanpm]

qmake (and configure, and Qt) does support this, I and many others do it all the time.

[user152508]

Can you tell me how to do it step by step please. I tried everything I can think of so far. Thank you

[AntonyFalegk]

ActivePerl is a must for out-of-tree builds, not a suggestion. @user152508, you are gettings this error because configure script fails to copy header files. I suspect you don't have ActivePerl's perl in your $PATH.

[Piotr Dobrogost]

Which program -prefix-install and -prefix /path are options for? They are not mentioned in the output of configure.exe --help

[mxcl]

I wrote that answer 16 months ago. It may be that the Qt configure has changed.

[asandroq]

I have the same problem as @user152508, and I definitely have ActivePerl in my %PATH%. It just doesn't work.

[Oliver Zendel]

I have the same problem too. I have ActivePerl in my path; I get numerous include files not found errors. The perl script is not properly changing the paths, but added an additional "..\..\" to every header file path in the build files.