[cmake-developers] [CMake] CMake 2.8.3-rc1 ready for testing!

[Clinton Stimpson]

On Thursday, September 23, 2010 01:40:02 pm Alexander Neundorf wrote:
> On Thursday 23 September 2010, Alexander Neundorf wrote:
> > On Wednesday 15 September 2010, David Cole wrote:
> > > I am happy to announce that CMake 2.8.3 has entered the release
> > > candidate stage! You can find the source and binaries here:
> > > http://www.cmake.org/files/v2.8/?C=M;O=D
> > > 
> > > Following is the list of changes in this release. (If you notice
> > > something missing please let me know and I will add it to the official
> > > release when 2.8.3 is finalized.)
> > > 
> > > Please try this version of CMake on your projects and report any
> > > issues to the list or the bug tracker.
> > 
> > Found two issues today (compared to 2.8.1, didn't check 2.8.2):
> > 
> > * cmake-gui doesn't remember whether "Advanced" checkbox was checked or
> > not
> > 
> > * FindQt4.cmake: in all previous versions it was possible to force a
> > special Qt version by presetting QT_QMAKE_EXECUTABLE. This is also what I
> > recommended many times on mailing lists to different people. It seems
> > this is not possible anymore.
> 
> I just checked, with cmake 2.8.2 also the output from QT_QMAKE_EXECUTABLE
> was preferred, even over CMAKE_PREFIX_PATH.
> 
> I checked what changed.
> In cmake <= 2.8.2 there is this code:
> 
> SET(QT_MODULES QtCore QtGui Qt3Support QtSvg QtScript QtTest QtUiTools
>                  QtHelp QtWebKit QtXmlPatterns phonon QtNetwork
> QtMultimedia QtNsPlugin QtOpenGL QtSql QtXml QtDesigner QtDBus
> QtScriptTools QtDeclarative)
> 
> ...
> 
> # find the libraries
> FOREACH(QT_MODULE ${QT_MODULES})
>   STRING(TOUPPER ${QT_MODULE} _upper_qt_module)
>   FIND_LIBRARY(QT_${_upper_qt_module}_LIBRARY_RELEASE
>                NAMES ${QT_MODULE}${QT_LIBINFIX} ${QT_MODULE}${QT_LIBINFIX}4
>                PATHS ${QT_LIBRARY_DIR} NO_DEFAULT_PATH
>       )
>   FIND_LIBRARY(QT_${_upper_qt_module}_LIBRARY_DEBUG
>                NAMES ${QT_MODULE}${QT_LIBINFIX}_debug
>                      ${QT_MODULE}${QT_LIBINFIX}d
> ${QT_MODULE}${QT_LIBINFIX}d4 PATHS ${QT_LIBRARY_DIR} NO_DEFAULT_PATH
>       )
> ENDFOREACH(QT_MODULE)
> 
> I.e. find_library() was called with NO_DEFAULT_PATH, so *only* the output
> from qmake was used.
> 
> Now in cmake 2.8.3 there is:
> 
> FIND_LIBRARY(QT_QTCORE_LIBRARY_RELEASE
>              NAMES QtCore${QT_LIBINFIX} QtCore${QT_LIBINFIX}4
>              HINTS ${QT_LIBRARY_DIR_TMP}
>     )
> FIND_LIBRARY(QT_QTCORE_LIBRARY_DEBUG
>              NAMES QtCore${QT_LIBINFIX}_debug QtCore${QT_LIBINFIX}d
>                    QtCore${QT_LIBINFIX}d4
>              HINTS ${QT_LIBRARY_DIR_TMP}
>     )
> ...
> IF(QT_QTCORE_LIBRARY_RELEASE)
>   GET_FILENAME_COMPONENT(QT_LIBRARY_DIR_TMP "${QT_QTCORE_LIBRARY_RELEASE}"
>                          PATH)
>   SET(QT_LIBRARY_DIR ${QT_LIBRARY_DIR_TMP} CACHE INTERNAL "Qt library dir"
>       FORCE)
>   SET(QT_QTCORE_FOUND 1)
> ELSEIF(QT_QTCORE_LIBRARY_DEBUG)
> ...
> 
> FOREACH(QT_MODULE ${QT_MODULES})
>   STRING(TOUPPER ${QT_MODULE} _upper_qt_module)
>   FIND_LIBRARY(QT_${_upper_qt_module}_LIBRARY_RELEASE
>                NAMES ${QT_MODULE}${QT_LIBINFIX} ${QT_MODULE}${QT_LIBINFIX}4
>                PATHS ${QT_LIBRARY_DIR} NO_DEFAULT_PATH
>       )
>   FIND_LIBRARY(QT_${_upper_qt_module}_LIBRARY_DEBUG
>                NAMES ${QT_MODULE}${QT_LIBINFIX}_debug
>                      ${QT_MODULE}${QT_LIBINFIX}d
> ${QT_MODULE}${QT_LIBINFIX}d4 PATHS ${QT_LIBRARY_DIR} NO_DEFAULT_PATH
>       )
> ENDFOREACH(QT_MODULE)
> 
> 
> I.e. now find_library() is called with HINTS, but not with NO_DEFAULT_PATH.
> In my case this has the effect that the Qt which is in CMAKE_PREFIX_PATH
> is preferred over the output from qmake, so I end up with LibQtCore.so
> from Qt 4.5 while my qmake is Qt 4.7:
> b283$ grep QMAKE CMakeCache.txt
> QT_QMAKE_EXECUTABLE:FILEPATH=/opt/qt4.7/bin/qmake
> QT_QMAKE_EXECUTABLE_LAST:INTERNAL=/opt/qt4.7/bin/qmake
> b283$ grep QTCORE_LIBRARY: CMakeCache.txt
> QT_QTCORE_LIBRARY:STRING=/opt/qt-4.5/qt/lib/libQtCore.so
> b283$ grep QTXML_LIBRARY: CMakeCache.txt
> QT_QTXML_LIBRARY:STRING=/opt/qt-4.5/qt/lib/libQtXml.so
> 
> 
> This was committed here:
> http://cmake.org/gitweb?p=cmake.git;a=commitdiff;h=b55da4c688bbf55b44290846
> 4e0f7e2e41c937a3 which has as commit message "Add cross-compiling support
> to FindQt4.cmake"
> 
> What speaks against adding the NO_DEFAULT_PATH again ?

It was removed so it would be possible to use CMAKE_PREFIX_* for cross-
compiling with Qt.  This is because the output of "qmake -query" cannot be 
relied on when cross-compiling, because it only has native Qt paths.

So are you saying the problem only comes up if CMAKE_PREFIX_PATH contains the 
root directory of a Qt installation that you don't want to use, and 
QT_QMAKE_EXECUTABLE is set to the qmake of the installation you want to use?

Clint