In commit "use export all symbols on cygwin" (2003-01-21) we started
passing -Wl,--export-all-symbols when linking shared libraries. Now
cygwin exports all symbols automatically if no symbols are explicitly
exported. When symbols are explicitly exported we want to honor that
narrow interface. Therefore this flag should not be passed.
Change based on patch from issue #10122.
The variable should contain the name of a library needed to link the
symbol equivalent to dlopen. On Cygwin no special library is needed,
and certainly not "gdi32".
Change based on patch from issue #10122.
After discussing with Brad and Clinton:
-the namespace for the imported targets is now "Qt4::", tested with Makefiles, Visual Studio and XCode projects
-the imported targets are always created
-if QT_USE_IMPORTED_TARGETS is set to TRUE (it defaults to FALSE), the QT_QTFOO_LIBRARY variables are set to point to these imported
targets, otherwise the old behaviour is used.
-on OSX if Qt has been found as framework, disable QT_USE_IMPORTED_TARGETS, since cmake doesn't handle the framework directory as location of the library correctly
Alex
-set the type of the IMPORTED libraries to UNKNOWN, this way also on Windows
only the "LOCATION" property has to be set
-the if() around the SET(QT_${basename}_FOUND 1) was useless (always true)
-the mapping of the configuration types DEBUG and PROFILE did not belong here
Alex
This commit syncs FindQt4.cmake again with KDEs version.
Now for every Qt library an imported target with the name
Qt4ImportedTarget__<LIBNAME> is created.
This way we can now finally handle the release and debug versions of the Qt
libraries correctly.
Also, if a Qt-using project A installs a file with exported targets, these
targets now depend on the imported Qt targets, e.g.
Qt4ImportedTarget__QtCore. The location of QtCore is then resolved at
buildtime of project B, which uses the exported targets from project A.
Before this patch the full path to the QtCore on the original build machine
of project A was stored, so this had to match the directory layout on the
build machine for project B.
Alex
While Cygwin supports linking directly to .dll files, the behavior is
now discouraged. All Cygwin packages now provide import libraries of
the form lib*.dll.a and CMake has built the import libraries for years.
We believe it is now safe to stop explicitly searching for .dll files
because their import libraries will always be available when the
corresponding header files are available. Users can always set
find_library cache entries to point at a .dll file by hand if they
really must use one.
Change based on patch from issue #10122.
Commit "Find locally installed software first" made /usr/local the first
prefix searched to be consistent with the Filesystem Hierarchy Standard:
http://www.pathname.com/fhs/
The standard also implies that the root prefix "/" should not have any
package or development files. The "/bin" and "/lib" directories should
have only minimal contents to boot the system. No "/include" ever
exists. This commit re-orders the search path prefix list from
/usr/local
/
/usr
to
/usr/local
/usr
/
to prefer package and development files over low-level system files.
See issue #10136.
On Cygwin /usr/lib == /lib and /usr/bin == /bin. This change also makes
search results report locations as "/usr/..." instead of "/lib/...".
See issue #10122.
Cygwin versions .dll files by putting the version number in the file
name. Our fix to issue #3571 taught CMake to do this, but it used the
VERSION target property. It is better to use the SOVERSION property
since that is the interface (rather than implementation) version.
Change based on patch from issue #10122.
When building on Cygwin without -mwin32, the _WIN32 macro may not be
defined. SharedForward must still set the PATH environment variable to
ensure runtime dependencies are found.
The 'ldd' wrapping feature uses 'cygcheck' for now since a real ldd tool
is not available in Cygwin 1.5. We can change to use the real ldd when
we choose to stop supporting legacy Cygwin and require 1.7.
We add compiler information files
Compiler/PathScale-<lang>.cmake
to specify PathScale compiler information for C, C++, and Fortran
languages. We use a macro in Compiler/PathScale.cmake to consolidate
the information common to all languages.
The commit "Drop -rdynamic from Linux build rules" removed default use
of the flag on Linux. It was expected to be compatible because any
project using plugins should set ENABLE_EXPORTS on its executables to
export their symbols for use by the plugins in a cross-platform way.
However, it is possible to build without ENABLE_EXPORTS and load plugins
that do not link to any symbols from the executable explicitly. These
plugins may need to see RTTI and other executable symbols needed by the
language implementation. Executables using such plugins were broken by
the change.
If we want to remove the -rdynamic flag in the future we should do so in
a compatible way. At that time we should also remove equivalent flags
on other platforms (like -bexpall on AIX). We will either need a policy
or an explicit API to disable symbol exports on executables.
The primary purpose of the above-mentioned commit was to avoid passing
the -rdynamic flag to compilers on Linux that do not support it. In
this commit we restore the flag but only on GNU and Intel compilers
which are known to support it.
See issue #9985.
Implement Fortran 32/64-bit ABI detection on some platforms. We need to
set CMAKE_SIZEOF_VOID_P correctly in Fortran-only projects so that the
find_library() command knows whether to look for 64-bit binaries. We
also detect ELF binaries to enable RPATH replacement. See issue #10119.
When kwsys is built using GCC visibility support can be used. This is similar
to the way that Windows exports symbols in DLLs, and requires projects that
build kwsys to change the default visibility using some compiler flags. See
http://gcc.gnu.org/wiki/Visibility for more details about GCC visibility.
Alexander Neundorf
KWSys Robot
Brad King
Clinton Stimpson
Bill Hoffman
James Bigler
Marcus Hanwell
Philip Lowman