One of Cygwin's goals is to build projects using the POSIX API with no
Windows awareness. Many CMake-built projects have been written to test
for UNIX and WIN32 but not CYGWIN. The preferred behavior under Cygwin
in such projects is to take the UNIX path but not the WIN32 path.
Unfortunately this change is BACKWARDS INCOMPATIBLE for Cygwin-aware
CMake projects! Some projects that previously built under Cygwin and
are Cygwin-aware when they test for WIN32 may now behave differently.
Eventually these projects will need to be updated, but to help users
build them in the meantime we print a warning about the change in
behavior. Furthermore, one may set CMAKE_LEGACY_CYGWIN_WIN32 to request
old behavior during the transition.
Normally we avoid backwards incompatible changes, but we make an
exception in this case for a few reasons:
(1) This behavior is preferred by Cygwin's design goals.
(2) A warning provides a clear path forward for everyone who may see
incompatible behavior, and CMAKE_LEGACY_CYGWIN_WIN32 provides a
compatibility option. The warning and compatibility option both
disappear when the minimum required version of CMake in a project is
sufficiently new, so this issue will simply go away over time as
projects are updated to account for the change.
(3) The fixes required to update projects are fairly insignificant.
Furthermore, the Cygwin distribution has no releases itself so project
versions that predate said fixes tend to be difficult to build anyway.
(4) This change enables many CMake-built projects that did not
previously build under Cygwin to work out-of-the-box. From bug #10122:
"I have built over 120 different source packages with (my patched)
CMake, including most of KDE4, and have found that NOT defining
WIN32 on Cygwin is much more accurate." -- Yaakov Selkowitz
A fully compatible change would require patches on top of these project
releases for Cygwin even though they otherwise need not be aware of it.
(5) Yaakov has been maintaining a fork of CMake with this change for the
Cygwin Ports distribution. It works well in practice. By accepting the
change in upstream CMake we avoid confusion between the versions.
CMake itself builds without WIN32 defined on Cygwin. Simply disable
CMAKE_LEGACY_CYGWIN_WIN32 explicitly in our own CMakeLists.txt file.
09d1c10 FortranCInterface: Recognize NAG Fortran module symbols
af2ad90 Add NAG Fortran compiler information files
24cc3d4 Recognize the NAG Fortran compiler
83892c4 Allow Fortran platform files to set empty values
fe3f878 Detect object files in implicit link information
Since commit aff31479 (Modernize GNU compiler info on Windows,
2009-12-02) the file Modules/Platform/Windows-g++.cmake has been unused.
It just includes the non-existent Modules/Platform/Windows-gcc.cmake so
remove it outright.
This moves Intel compiler info on Windows into new-style modules
Platform/Windows-Intel-<lang>.cmake
using language-independent helper module
Platform/Windows-Intel.cmake
to define macros consolidating the information.
Commit 4430bccc (Change the way 32/64 bit compiles are detected with
MSVC and intel, 2009-11-19) added detection of the target processor to C
and CXX language builds with MS and Intel tools. Do the same for Intel
Fortran for Windows (ifort). Use /machine:<arch> to link executables.
On Linux the NAG Fortran compiler uses gcc under the hood to link. Use
"-Wl,-v" to pass "-v" to the underlying gcc compiler to get verbose link
output. Detect the NAG Fortran directory (using -dryrun) and then honor
object files in the directory referenced in the implicit link line.
Pass real linker options with "-Wl,-Xlinker,". The -Wl, gets through
the NAG front-end and the -Xlinker gets through the gcc front-end.
The Mac linker defines -headerpad_max_install_names and the GCC
front-end passes this flag through. The PGI compiler does not know
about this flag, so we must use -Wl,-headerpad_max_install_names to pass
it to the linker instead.
Use a combination of response files and the archiver to support long
object file lists that do not fit in the Windows command-line length
limit. This can work only with GCC >= 4 because the MinGW GCC 3.x
front-ends do not support response-file syntax.
Set CMAKE_PLATFORM_REQUIRED_RUNTIME_PATH in the HP-UX platform file to
tell CMake to pass -Wl,+b,/usr/lib no matter whether RPATH is enabled or
not. This corrects the behavior of -Wl,+nodefaultrpath to look in this
default library path as documented.
Include this prefix in CMAKE_SYSTEM_PREFIX_PATH so that it will be used
for all find* commands. Previously only find_library and find_path
would look under /opt/local/lib and /opt/local/include, respectively.
BlueGeneP-base: Internal base shared by static and dynamic files
BlueGeneP-static: Platform file for all-static builds
BlueGeneP-dynamic: Platform file for "default" dynamic builds
Use response files for C and CXX languages with the Intel compiler on
Windows. We already used them for Fortran. This enables creation of
libraries and executables with a very large number of object files.
Tru64's make(1) resolves relative paths in "include" directives with
respect to the includer. This is inconsistent with all other known make
tools. Note that this make tool treats the path literally so we cannot
use our standard FULL path code which escapes spaces. Instead qualify
the paths with $(CMAKE_BINARY_DIR) to avoid the problem.
Commit 82c081ba (Fix rpath-link flag for SunPro C++ on Linux,
2009-07-13) taught CMake to pass '-rpath-link' because SunPro C++ 5.9
does not support '-Wl,'. Now SunPro C++ 5.11 does not recognize the
option without using '-Wl,'. Detect whether to use '-Wl,' based on the
output of "sunCC -flags".
The ENABLE_EXPORTS property exports all symbols from executables on
UNIX-like platforms, typically for use by plugins. Honor this behavior
on Cygwin. See issue #10122.
Map to the platform and compiler information for GNU because the
compilers are command-line compatible for common operations. Later we
can add Clang-specific features as necessary. We honor the preferred
capitalization is "Clang", not the common mis-spelling "CLang".
The expectation of users of the MSVC60, MSVC70, MSVC71, MSVC80, MSVC90
and the new MSVC10 variables is that at most one of them will be set
for any given build tree. This change enforces that expectation for
build trees using Makefile generators. It also fixes the one mismatch
in that expectation to be found in the Visual Studio generator world:
previously, the VS 7.1 generator would set *both* MSVC70 and MSVC71;
now, it only sets MSVC71.
With these changes, user expectations are now met, and the recently
introduced CheckCompilerRelatedVariables test should pass everywhere.
As reported on the mailing list, find_path/file/library/program() basically don't work
at all if CMAKE_FIND_ROOT_PATH is set and searching in the host system directories
is disabled. This patch adds /include, /lib and /bin to the search directories, so they
will be appended to CMAKE_FIND_ROOT_PATH so this will work for the "Generic" platform (embedded
systems without OS)
Alex
Detect the runtime linker's search path and add to the compile time
linker's search path. This is needed because OpenBSD's static linker
does not search for shared library dependencies in the same places as
the runtime linker.
Commit "Modernize GNU compiler info on Windows" (2009-12-02) reorganized
GNU flags on Windows but let -fPIC slip through for compilation of
objects in shared libraries. While this flag is valid on most GNU
compiler platforms we need to suppress it in Windows-GNU.cmake just as
we already do in CYGWIN-GNU.cmake.
Brad King
Yaakov Selkowitz
Bill Hoffman
Todd Gamblin
Arjen Verweij
Pino Toscano
David Cole
Alex Neundorf
Chuck Atkins