On WinCE we must link both shared libraries and executables with the
/subsystem:windowsce flag. Teach Platform/Windows-MSVC to pass it
to the linker in both cases.
Suggested-by: Gunnar Roth <gunnar.roth@gmx.de>
Call the generator "Visual Studio 14" without any year because this
version of VS does not provide a year in the product name.
Copy cmGlobalVisualStudio12Generator to cmGlobalVisualStudio14Generator
and update version numbers accordingly. Add the VS14 enumeration value.
Teach the platform module Windows-MSVC to set MSVC14 and document the
variable. Teach module InstallRequiredSystemLibraries to look for the VS
14 runtime libraries.
Teach tests CheckCompilerRelatedVariables, VSExternalInclude, and
RunCMake.GeneratorToolset to treat VS 14 as they do VS 10, 11, and 12.
Co-Author: Pawel Stopinski <diokhan@go2.pl>
Create a Platform/Android module that includes Platform/Linux since
Android is based on Linux. Provide only the minimal settings needed to
get builds with Android NDK toolchains to work.
Disable use of RPATH since the Android loader ignores it and we cannot
predict the install destination anyway.
Android supports soname but shared library names must end in ".so" and
we cannot represent the versioned names with associated symlinks on all
host operating systems anyway. However, we do want the SONAME of
library files to be set so that linking to them by path to the library
file produces NEEDED entries with the soname and not the path. Add a
new CMAKE_PLATFORM_NO_VERSIONED_SONAME setting to tell the
cmTarget::GetLibraryNames method that not to use the VERSION or
SOVERSION target properties in the soname.
Add to the Platform/Windows-GNU module list of VS registry entries those
for VS 2013. Also add the name "vcvars64.bat" used by VS 10 and above
for 64-bit tools.
Just like -I flag has its -isystem counterpart which marks an include
directory as a system directory and prevents unwanted warnings, on Apple
systems there is -iframework -- a system directory replacement for -F.
Use this flag to implement include_directories(SYSTEM) for frameworks.
For example if one installs Xcode 4.6 on OS X 10.9, it doesn't contain
a 10.9 SDK, so fallback to the next newest version which, in this case,
happens to be a 10.8 SDK.
This fixes bug #14572.
Initialize variables CMAKE_OSX_SYSROOT, CMAKE_OSX_DEPLOYMENT_TARGET, and
CMAKE_OSX_ARCHITECTURES prior to enabling any languages. This will
allow compiler identification to consider these values.
Extend CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES with these paths. We
already have the equivalents under /usr. Systems that have these
directories have their dynamic loaders configured already. Do not allow
them to appear in the RPATH explicitly.
f21ac16e Replace MATCHES test on numbers with EQUAL test
7eacbaed Replace MATCHES ".+" tests with NOT STREQUAL ""
3a71d34c Use CMAKE_SYSTEM_NAME instead of CMAKE_SYSTEM where sufficient
b0b4b460 Remove .* expressions from beginning and end of MATCHES regexs
5bd48ac5 Replace string(REGEX REPLACE) with string(REPLACE) where possible
2622bc3f Clean up usage of if(... MATCHES regex) followed string(REGEX REPLACE regex)
Since commit v2.6.0~388 (Added build rule variables
CMAKE_<LANG>_ARCHIVE_..., 2008-01-29) we use separate "ar cr ..." and
"ar r ..." steps to incrementally add a large list of object files to an
archive. Since the "r" command replaces existing objects of the same
name in an archive, if multiple objects have the same file name and
appear in separate append steps then one overwrites the other. Instead,
use "ar cq ..." and "ar q ..." to always append to the archive.
We already remove the archive before creating it so this will not cause
objects to be appended to existing archives on incremental rebuilds.
* Remove Watcom linker caseexact options already defined in system
definition.
* Use win_dll system for SHARED_LIBRARY and SHARED_MODULE.
* Use explicit target definition -bt=.. option for proper initialization
of compiler Windows environment (predefined macros)
* Reorganize compiler options to global options and configuration
specific options
* Use option to optimize out stack checking code for release version
Drop the CMAKE_NO_QUOTED_OBJECTS internal variable from the Makefile
generators. The underlying problem is with the Watcom linker, not with
WMake. The Watcom linker wants object files to be single-quoted. Add
<LINK-RULE>_USE_WATCOM_QUOTE platform information variables to tell the
generators to use Watcom-style single quotes for object files on link
lines.
On Windows, Watcom uses the GetCommandLine API to get the original
command-line string and do custom parsing that expects single quotes.
On POSIX systems, Watcom approximates the original command line by
joining all argv[] entries separated by a single space. Therefore we
need to double-quote the single-quoted arguments so that the shell does
not consume them and they are available for the parser to see.
64c2342a Watcom: Enable 'WMake Makefiles' generator on Linux
5d9aa66c Watcom: Introduce OpenWatcom compiler id and fix compiler version
9292d3b8 Watcom: Detect compiler target architecture and platform
fbc883c9 Watcom: Add one blank line to Makefile for better readability
Distinguish "Open Watcom" from old "Watcom" by introducing a new
"OpenWatcom" compiler id. The __WATCOMC__ format is "VVRP" for Watcom
and "VVRP + 1100" for Open Watcom.
Work around the command-line-length limit by using an @linklibs.rsp
response file to pass the flags for link libraries. This allows
very long lists of libraries to be used in addition to the existing
support for passing object files via response file.
Suggested-by: Peter Keuschnigg <peter.keuschnigg@pmu.ac.at>
Create each DLL import library by passing "option implib=..." to the
linker for its SHARED library. This works even when there are no
symbols to be exported. Leave the option out for MODULE libraries
because we do not need an import library for them. For executables,
retain the separate invocation of wlib because we want an import
library only when the ENABLE_EXPORTS property is set, and in that
case the project should provide symbols.
Suggested-by: J Decker <d3ck0r@gmail.com>
Since commit v2.8.12~437^2~2 (VS: Separate compiler and linker PDB files
2013-04-05) we no longer set /Fd with the PDB_NAME or PDB_OUTPUT_DIRECTORY
properties. Those properties now exclusively handle linker PDB files.
Since STATIC libraries do not link their compiler PDB file becomes more
important. Add new target properties "COMPILE_PDB_NAME[_<CONFIG>]" and
"COMPILE_PDB_OUTPUT_DIRECTORY[_<CONFIG>]" to specify the compiler PDB
file location and pass the value to the MSVC /Fd option.
Create platform information modules Platform/Darwin-Intel-(C|CXX).cmake
and helper module Platform/Darwin-Intel.cmake. Teach existing module
Platform/Darwin-Intel-Fortran.cmake to use the helper too. Move
information from Platform/Darwin-icc.cmake into these files and drop
information already in Platform/Darwin.cmake to avoid duplication.
Introduce policy CMP0047 to control resetting the id for
compatibility.
De-duplicate content in the QNX platform file by including the GNU
one. QNX is a form of GNU platform.
Do not clear CMAKE_SHARED_LIBRARY_${lang}_FLAGS variables. They
are populated again later by the Compiler/GNU.cmake file anyway.
Modify the CMAKE_CXX_COMPILE_OBJECT variable only when the QCC
compiler id is in use, and the language is CXX. Use the QNX
recommended flag for QCC instead of the gcc compatible -x flag.
Populate new module files to handle system includes and depfiles
when using the QCC compiler.
Remove code which unsets the system include and depfiles related
variables. When a GNU driver is used instead of the QCC one, the
appropriate flags will be used. These variables were previously
cleared for lowest-common-denominator compatibility with both
drivers.
This variable can be useful in cross-compiling contexts where the
sysroot is read-only or where the sysroot should otherwise remain
pristine.
If the new CMAKE_STAGING_PREFIX variable is set, it is used instead
of CMAKE_INSTALL_PREFIX when generating the installation rules in
cmake_install.cmake.
This way, the CMAKE_INSTALL_PREFIX variable
always refers to the installation prefix on the target device, regardless
of whether host==target.
If any -rpath paths passed to the linker contain the CMAKE_STAGING_PREFIX,
the matching path fragments are replaced with the CMAKE_INSTALL_PREFIX.
Matching paths in the -rpath-link are not transformed.
The cross-prefix usr-move workaround is assumed not to require extension
regarding CMAKE_STAGING_PREFIX. The staging area is a single prefix, so
there is no scope for cross-prefix symlinks. The CMAKE_INSTALL_PREFIX
is still used to determine the workaround path, and that variable
remains the relevant one even if CMAKE_STAGING_PREFIX is used. If the
generated export files are deployed to the target, the workaround
will still be in place, and still be employed if required.
For clang, this allows passing -target <triple> to the compiler, and
for qcc, -V<arch> using toolchain files containing something like
set(triple arm-linux-gnueabihf)
set(CMAKE_C_COMPILER "/usr/bin/clang")
set(CMAKE_C_COMPILER_TARGET ${triple})
set(CMAKE_CXX_COMPILER "/usr/bin/clang++")
set(CMAKE_CXX_COMPILER_TARGET ${triple})
or
set(arch gcc_ntoarmv7le)
set(CMAKE_C_COMPILER /opt/qnx650/host/linux/x86/usr/bin/qcc)
set(CMAKE_C_COMPILER_TARGET ${arch})
set(CMAKE_CXX_COMPILER /opt/qnx650/host/linux/x86/usr/bin/QCC)
set(CMAKE_CXX_COMPILER_TARGET ${arch})
Both clang and qcc are inherently cross compiler( driver)s.
When cross-compiling with clang, use the CMAKE_${lang}_COMPILER_TARGET
as the _CMAKE_TOOLCHAIN_PREFIX to find the appropriate binutils.
When cross-compiling with QNX qcc, use the CMAKE_${lang}_COMPILER_TARGET
to set the appropriate _CMAKE_TOOLCHAIN_PREFIX.
In certain scenarios, it is preferable to keep a 'dirty' install prefix
than to clear it, and to expect that content will not be found there.
Add a CMAKE_FIND_NO_INSTALL_PREFIX variable that can be set to disable
searching the install prefix.
Drop all behavior activated by setting CMAKE_BACKWARDS_COMPATIBILITY to
a value lower than 2.4, and generate an error when projects or the user
attempt to do so. In the error suggest using a CMake 2.8.x release.
Teach cmake_minimum_required to warn about projects that do not require
at least CMake 2.4. They are not supported by CMake >= 3.0.
Replace the documentation of CMAKE_BACKWARDS_COMPATIBILITY with a
reference to policy CMP0001.
In generators such as Ninja that can run multiple "cl" processes that
refer to the same compiler .pdb file (/Fd) at the same time, MSVC from
Visual Studio 2013 complains:
fatal error C1041: cannot open program database '.../vc120.pdb';
if multiple CL.EXE write to the same .PDB file, please use /FS
According to "cl /?":
/FS force to use MSPDBSRV.EXE
Add the flag to compilation lines for this compiler version just after the
/Fd option.
Teach CMake(C|CXX|Fortran)CompilerId* to report the MSVC version
simulated by the Intel compiler, if any. Refactor the Windows-Intel
platform information helper module to load Windows-MSVC instead of
duplicating the information. Teach Windows-MSVC to understand when
it is loaded as the simulated Fortran compiler (its preprocessor is
simulated).
Compilers for languages other than C and C++ on OS X may not understand
the -F framework search flag. Create a new platform information
variable CMAKE_<LANG>_FRAMEWORK_SEARCH_FLAG to hold the flag, and set it
for C and CXX lanugages in the Platform/Darwin module.
Reported-by: Vittorio Giovara <vittorio.giovara@gmail.com>
54ef2be Haiku: Include files cleanup in cmCTest
38d5555 Haiku: Remove outdated preprocessor checks
1dc61f8 Haiku: Remove use of B_COMMON_DIRECTORY
7ebc1cb Haiku: Several fixes to platform module
1763c31 Set policy CMP0025 to NEW while building CMake itself
aa53ee5 Add policy CMP0025 for Apple Clang compiler id compatibility
ab65862 Clang: Add separate "AppleClang" compiler id
* Do not define BEOS anymore (this includes workarounds which we don't
need most of the time in Haiku, so we prefer opt-in IF(HAIKU) in the
cmake files instead).
* On the other hand, do define UNIX (we are trying to be compliant) and
HAIKU (there is still a number of things we don't do like the
average UNIX clone)
* Do not use UnixPaths, as our filesystem hierarchy isn't anything like
what it expects.
* Do not use -nostart, which the compiler doesn't know about anymore.
This used to be an Haiku extension to gcc, and is equivalent to
-shared which is the default gcc option.
* While "dl" functions are provided in libroot, this is always
implicitly linked so there is no need to tell cmake about it.
* Forcing position-independent code is not needed, so remove it.
* On the other hand, include appropriate linker options for executables
and shared libraries.
* Support for the two available compilers in Haiku (gcc2 and gcc4) and
pick the right headers and libraries according to the currently
selected one.
* With the adoption of the package manager, the directory layout was
changed. Tell cmake where to look for header files and libraries.
* As we don't define BEOS anymore, enable the workaround we still need
for HAIKU as well. This is the lack of a libm (it is part of the
implicitly linked in libroot)
Applied-by: Rolf Eike Beer <eike@sf-mail.de>
Apple distributes their own Clang build with their own version numbers
that differ from upstream Clang. Use the __apple_build_version__ symbol
to identify the Apple Clang compiler and report the Apple Build Version
as the fourth version component in CMAKE_<LANG>_COMPILER_VERSION. Add
Compiler/AppleClang-<lang> and Platform/Darwin-AppleClang-<lang> modules
that simply include the upstream equivalents.
Fix comparisons of CMAKE_<LANG>_COMPILER_ID to Clang in CMake's own
source and tests to account for AppleClang.
Teach the compiler identification preprocessor tests to report when
Clang simulates MSVC, and what version. If not MSVC, assume GNU.
Teach compiler information modules Clang-(C|CXX) to recognize when Clang
simulates MSVC and skip loading the GNU information.
Teach the Windows-MSVC platform information to recognize when it is
loaded as the simulated compiler and use that version information
instead of the real compiler's (different) version scheme.
Add platform modules Windows-Clang-(C|CXX) and support module
Windows-Clang to load either Windows-MSVC or Windows-GNU and wrap
the corresponding information macros.
In Modules/Platform/Darwin.cmake set CMAKE_SYSTEM_FRAMEWORK_PATH to
include framework directories from inside the system SDK corresponding
to CMAKE_OSX_SYSROOT.
Suggested-by: Sean McBride <sean@rogue-research.com>
In commit bd827f98 (Use COFF file header header for architecture
detection, 2013-08-05) the MSVC_<lang>_ARCHITECTURE_ID value computed by
CMakeDetermineCompilerId.cmake changed for WinCE architectures to be the
exact architecture read from the PE header. Fix platform preprocessor
definitions in Modules/Platform/Windows-MSVC.cmake to correspond to the
architecture family (ARM or SHx) instead of the specific architecture.
In commit 8fcf0ab0 (Add support for new Windows CE compiler, 2013-08-04)
we made corelibc conditional on the MSVC version, but the version value
was incorrect. Update it to use corelibc for VS 2008 and below.
In commit fb9f73de (MSVC: Invoke 'link' directly for executables,
2013-04-08) we forgot to remove the /link option handling added by
commit e31df039 (Ninja: move <OBJECTS> in front of the first linker
option, 2012-09-27) to the Platform/Windows-MSVC module. Drop it now.
Since commit 95f78e08 (OS X: Search for SDK based on deployment target,
2013-08-02) we select the default OS X SDK path to match the deployment
target. Fix this behavior in the case that the matching SDK does not
exist and fall back to the SDK for the current host OS X version.
Teach modules CMakeDetermineCompiler and CMakeUnixFindMake to ask Xcode
where to find the compiler or make tools, using 'xcrun --find', if none
is found in the PATH. Teach module Platform/Darwin to add the path to
the SDK to CMAKE_SYSTEM_PREFIX_PATH so that find_* command look there.
Also add the SDK /usr/include directory to the implicit include list in
CMAKE_${lang}_IMPLICIT_INCLUDE_DIRECTORIES to suppress explicit -I
options for it.
When available, use CMAKE_OSX_DEPLOYMENT_TARGET instead of the host OS X
version to select the default SDK. This makes sense because one should
use the SDK matching the deployment target.
Suggested-by: John Ralls <jralls@ceridwen.us>
The linker flags for setting the compatibility and current versions of
libraries on Darwin are set for the supported Fortran compilers.
Set CMAKE_Fortran_CREATE_SHARED_LIBRARY for the NAG Fortran compiler to
have no space after <SONAME_FLAG> so the NAG compiler can parse the
argument correctly.
Copy cmGlobalVisualStudio11Generator to cmGlobalVisualStudio12Generator
and update version numbers accordingly. Add the VS12 enumeration value.
Add module CMakeVS12FindMake to find MSBuild. Look for MSBuild in its
now-dedicated Windows Registry entry. Teach the platform module
Windows-MSVC to set MSVC12 and document the variable. Teach module
InstallRequiredSystemLibraries to look for the VS 12 runtime libraries.
Teach tests CheckCompilerRelatedVariables, Preprocess, VSExternalInclude,
and RunCMake.GeneratorToolset to treat VS 12 as they do VS 10 and 11.
Inspired-by: Minmin Gong <minmin.gong@gmail.com>
Leave other flags directly in the Makefile command lines and outside
any special inline response file syntax. Otherwise Borland does
not support flags with quotes in response files.
For clang, this allows passing -target <triple> to the compiler, and
for qcc, -V<arch> using toolchain files containing something like
set(triple arm-linux-gnueabihf)
set(CMAKE_C_COMPILER "/usr/bin/clang")
set(CMAKE_C_COMPILER_TARGET ${triple})
set(CMAKE_CXX_COMPILER "/usr/bin/clang++")
set(CMAKE_CXX_COMPILER_TARGET ${triple})
or
set(arch gcc_ntoarmv7le)
set(CMAKE_C_COMPILER /opt/qnx650/host/linux/x86/usr/bin/qcc)
set(CMAKE_C_COMPILER_TARGET ${arch})
set(CMAKE_CXX_COMPILER /opt/qnx650/host/linux/x86/usr/bin/QCC)
set(CMAKE_CXX_COMPILER_TARGET ${arch})
Both clang and qcc are inherently cross compiler( driver)s.
dc1d025 OS X: Add test for rpaths on Mac.
8576b3f OS X: Add support for @rpath in export files.
00d71bd Xcode: Add rpath support in Xcode generator.
94e7fef OS X: Add RPATH support for Mac.
RPATH support is activated on targets that have the MACOSX_RPATH
property turned on.
For install time, it is also useful to set INSTALL_RPATH to help
find dependent libraries with an @rpath in their install name.
Also adding detection of rpath conflicts when using frameworks.
Initialize the CMAKE_CONFIGURATION_TYPES cache entry early during
EnableLanguage like the Xcode generator does. Avoid depending on
the MSVC compiler information module to do it. Otherwise code like
project(MyProj NONE)
sets CMAKE_CONFIGURATION_TYPES late (in GenerateConfigurations), and
to only "Debug" and "Release" instead of the standard set of 4.
Reported-by: Paul Smith <paul@mad-scientist.net>
Commit dac78148 (...makes the mingw cross compiler work out of the
box..., 2007-08-02) added to CMAKE_SYSTEM_PROGRAM_PATH and
CMAKE_SYSTEM_LIBRARY_PATH paths like "/bin" and "/lib" with no Windows
drive letter so that cross-compiling to Windows from Linux would search
these paths under CMAKE_FIND_ROOT_PATH. Later commit 2a782880 (...use
CMAKE_SYSTEM_PREFIX_PATH when possible, 2008-01-16) generalized this
approach by instead adding "/" to CMAKE_SYSTEM_PREFIX_PATH.
Both commits assumed that the paths would never match anything on
Windows hosts without a drive letter. However, Windows evaluates these
paths relative to the current working drive letter so find_* commands
may report paths like "/lib/..." when paths like "c:/lib/..." exist on
what happens to be current drive. Such drive-less paths are not
reliable when the working drive changes, so we should not use them.
Fix WindowsPaths.cmake to add '/' to CMAKE_SYSTEM_PREFIX_PATH only when
cross-compiling to Windows from a non-Windows host. This will avoid
searching and finding local paths without a drive letter on Windows.
Update the CMAKE_<LANG>_LINK_EXECUTABLE rule variable to invoke the
linker directly instead of through the compiler. We already do this
for DLL linking with CMAKE_<LANG>_CREATE_SHARED_LIBRARY.
This also works around a VS 6 cl bug. While invoking the link tool
internally it fails to correctly quote flags like /pdb:... with spaces
in the value.
The MS tools create two types of PDB files as explained here:
http://msdn.microsoft.com/en-us/library/yd4f8bd1%28v=vs.71%29.aspxhttp://msdn.microsoft.com/en-us/library/yd4f8bd1%28v=vs.80%29.aspxhttp://msdn.microsoft.com/en-us/library/yd4f8bd1%28v=vs.90%29.aspxhttp://msdn.microsoft.com/en-us/library/yd4f8bd1%28v=vs.100%29.aspx
One is created by the compiler (/Fd) and the other by the linker (/pdb).
The two options should not specify the same file. Split them up.
In the VS IDE generators, simply drop ProgramDataBaseFileName to
take the VS default "/Fd$(IntDir)vc$(PlatformToolsetVersion).pdb".
In the Makefile generators, set "/Fd" on the compile line to be
the directory containing object files (with a trailing slash the
compiler will add the "vc$(PlatformToolsetVersion).pdb" filename
automatically). Drop the /Fd option from the exe link command
line and add "/pdb" instead (already done for dll linking).
Update these rules for both MSVC and Intel tools.
Drop support for PDB_OUTPUT_DIRECTORY and PDB_NAME in STATIC
libraries because the generated .pdb files are only from /Fd
and not real linker-generated .pdb files. Update documentation to
clarify that the PDB_* properties are only for linker .pdb files.
This regresses the PDBDirectoryAndName test for STATIC libraries.
Since it is not clear at this time what should be done for STATIC
library .pdb files, comment out the relevant portion of the test
and leave a TODO comment.
The flag was added incorrectly by commit 9c3a6eb4 (Need -brtl when creating
shared libraries, 2003-05-16). According to "man ld" the -G option implies
"-brtl -bnortllib ...", -brtl implies "-brtllib", and -brtllib should only be
used for executables, not shared libraries. Therefore it is incorrect and
unnecessary to specify -brtl explicitly after -G.
Reported-by: Kevin Burge <kcburge@gmail.com>
The GNU compiler front-ends on AIX invoke the linker with flags of the
form "-L/path/to/gnu/runtime/lib" to tell ld where to find the language
runtime libraries. They depend on the default libpath behavior
documented in "man ld" to add the -L paths also to the runtime libpath
so the dynamic loader can find the language runtime libraries. This
differs from platforms whose linkers have distinct -rpath flags that
non-system compilers can use to tell the dynamic loader where to find
their language runtime libraries.
Since commit 96fd5909 (Implement linking with paths to library files,
2008-01-22) CMake always passes "-Wl,-blibpath:" followed by any
project-defined RPATH plus "/usr/lib:/lib" in order to explicitly set
the runtime libpath and avoid getting all the project -L paths in the
runtime libpath. The explicit libpath prevents the GNU compiler runtime
library -L paths from being placed in the libpath and then the dynamic
loader fails to find the language runtime libraries.
CMake already detects the implicit link directories for each language
since commit 07ea19ad (Implicit link info for C, CXX, and Fortran,
2009-07-23). Add the implicit link directories to the explicit runtime
libpath for GNU compilers on AIX to fix this use case.
Since commit c70beb4b (change the default borland stack size, 2003-05-05),
commit 1b572eb9 (remove -H flags, 2003-05-08), and commit 2d411398 (Stack size
in generated programs should be 10 meg, 2003-06-12) CMake adds link flags to
select a 10MB stack. At the time this was for consistency with our behavior on
MS, but that was recently removed by commit 51af1da3 (Remove "/STACK:10000000"
from default linker flags, 2012-11-23).
Change our Embarcadero link flags to select the default stack and heap settings
according to the compiler documentation. This is more reliable than leaving
the flags out completely as it has been reported that the linker does not
always use its documented defaults.
Suggested-by: Mathäus Mendel <contato@mathausmendel.com>
Previously we hard-coded a list of implicit framework directories but
did not account for CMAKE_OSX_SYSROOT or for changes to the list across
OS X versions. Instead we should automatically detect the framework
directories for the active toolchain.
The parent commit added the "-Wl,-v" option to ask "ld" to print its
implicit directories. It displays a block such as:
Framework search paths:
/...
Parse this block to extract the list of framework directories.
Detection may fail on toolchains that do not list their framework
directories, such as older OS X linkers. Always treat the paths
<sdk>/Library/Frameworks
<sdk>/System/Library/Frameworks
<sdk>/Network/Library/Frameworks # Older OS X only
/System/Library/Frameworks
as implicit. Note that /System/Library/Frameworks should always be
considered implicit so that frameworks CMake finds there will not
override the SDK copies.
We detect the implicit link directories for the toolchain by adding a
flag to get verbose output from the compiler front-end while linking the
ABI detection binary. Newer OS X toolchains based on Clang do not add
the implicit link directories with -L options to their internal
invocation of "ld". Instead they use a linker that comes with the
toolchain and is already configured with the proper directories.
Add the "-Wl,-v" option to ask "ld" to print its implicit directories.
It displays them in a block such as:
Library search paths:
/...
Parse this block to extract the implicit link directories.
While at it, remove the checks introduced by commit efaf335b (Skip
implicit link information on Xcode, 2009-07-23) and commit 5195a664
(Skip implicit link info for multiple OS X archs, 2009-09-22). Discard
the non-system link directories added by Xcode. Discard all detected
implicit libraries in the multi-architecture case but keep the
directories. The directories are still useful without the libraries
just to suppress addition of explicit -L options for them.
Modern apps that use multiple threads do NOT want 10 Megabytes of RAM
per thread being used for each thread's stack... Just leave off the
/STACK: argument, and let the compiler use a reasonable default value
for the stack size.
If existing single-threaded apps require the /STACK: argument because
they do need a very large stack size, they can add the flag in their
own CMakeLists files.
From the option documentation of VS >= 7.1:
"In earlier versions of Visual C++, the compiler used several discrete
heaps, and each had a finite limit. Currently, the compiler dynamically
grows the heaps as necessary up to a total heap size limit, and requires
a fixed-size buffer only to construct precompiled headers. Consequently,
the /Zm compiler option is rarely necessary."
http://msdn.microsoft.com/en-us/library/bdscwf1c.aspx
Suggested-by: Adam Moss <adam@broadcom.com>
Xcode 3.2.6 is known to break the SDK Library/Frameworks layout.
Detect and warn about this case to tell users to fix their system.
Reported-by: Matthew Brett <matthew.brett@gmail.com>
Since commit 43b74793 (OS X: Further improve default CMAKE_OSX_SYSROOT
selection, 2012-09-21) we choose a default CMAKE_OSX_SYSROOT only when
one is needed. However, the change forgot that we require a sysroot
when a deployment target is requested. Teach Darwin.cmake to choose a
default CMAKE_OSX_SYSROOT when CMAKE_OSX_DEPLOYMENT_TARGET is set.
Reported-by: Matthew Brett <matthew.brett@gmail.com>
Reported-by: Bradley Giesbrecht <pixilla@macports.org>
Remove ancient checks left from commit f5d95fb0 (Complete rework of
makefile generators expect trouble, 2002-11-08). Modern FreeBSD and
NetBSD platforms support shared libraries. When cross-compiling the
/usr/include/dlfcn.h may not exist on the host but the toolchain still
supports shared libraries.
In the response file also linker options could be passed,
and because <OBJECTS> is replaced by a response file, it
is necessary that no compiler option follows <OBJECTS>.
This reverts commit 5598d9b2a0.
Since commit f1670ab1 (Ninja: don't confuse ninja's rsp files with
nmake's, 2012-09-26) Ninja generator response files are placed in
CMakeFiles/ so the previously existing check already avoids expanding
them.
Since commit 1786b121 (OS X: Allow CMAKE_OSX_SYSROOT to be a logical SDK
name, 2012-09-21) we support names like "macosx" or "macosx10.7" as the
specified value of CMAKE_OSX_SYSROOT. Extend the SDK name->path
conversion to save the original value and also convert into a temporary
variable for the Xcode generator. Re-implement the deployment target
sanity check to detect the version from the transformed path.
Since commit 230ea218 (OS X: Improve default CMAKE_OSX_SYSROOT
selection, 2012-09-21) we always set CMAKE_OSX_SYSROOT if any SDK is
found in order to support Makefile generator builds with Xcode >= 4.3
without the command-line tools installed. However, in the basic
POSIX-only case of the Makefile generator with command-line tools and no
CMAKE_OSX_ARCHITECTURES we should not select any SDK by default.
Xcode supports SDKROOT values that just name an SDK rather than
specifying the full path to it. Recognize these values and handle them.
For Xcode we just put the value directly in the generated project file.
For Makefile generators we ask xcodebuild to provide the full path to
the named SDK.
Suggested-by: Jason DiCioccio <jd@ods.org>
Simplify the search for OSX_DEVELOPER_ROOT and allow it to fail if no
"/Developer" exists. When it does exist, always find a MacOSX SDK
inside it to use as the default CMAKE_OSX_SYSROOT. Otherwise set
CMAKE_OSX_SYSROOT to empty.
Drop the last use of CMAKE_OSX_SYSROOT_DEFAULT. Replace internal
platform variable CMAKE_${lang}_HAS_ISYSROOT with a more general
CMAKE_${lang}_SYSROOT_FLAG variable. If the -isysroot flag exists and
CMAKE_OSX_SYSROOT points to an SDK (not "/") then always add it to
compiler command lines. This is already done in the Xcode IDE.
Clang has the same interface as GNU except that we do not need to test
for the deployment target and sysroot flags. Simply set variables
CMAKE_${lang}_HAS_ISYSROOT
CMAKE_${lang}_OSX_DEPLOYMENT_TARGET_FLAG
to true because every version of Clang available on OS X supports these
flags.
This enables CMake to create Makefiles targeting Windows CE devices.
CMake needs to be run within a cross compile command prompt and requires
a toolchain file which sets CMAKE_SYSTEM_NAME to "WindowsCE" and
optionally CMAKE_SYSTEM_VERSION.
In commit 485a940e (VS: Simplify MSVC version reporting, 2012-08-23) we
accidentally flipped the 0/1 values of MSVC_IDE. Flip them back and
teach the CheckCompilerRelatedVariables test to check the variable.
Remove the old-style "Windows-cl.cmake" and its helper "cl.cmake". Load
the information through new-style "Platform/Windows-MSVC-<lang>.cmake"
files. Factor information common to C and CXX into a helper file
"Platform/Windows-MSVC.cmake" loaded from the per-language files.
Teach Windows-cl.cmake to use CMAKE_(C|CXX)_COMPILER_VERSION to set the
"MSVC##" and MSVC_VERSION variables. It no longer needs the IDE generator
to dictate the version or to detect the version by running the
command-line tool for NMake and Ninja generators. Drop configuration of
CMakeCPlatform.cmake and CMakeCXXPlatform.cmake from Windows-cl.cmake.in
because all the results it saved are now cheap to compute every time.
At the top of a build tree we configure inside the CMakeFiles directory
files such as "CMakeSystem.cmake" and "CMake<lang>Compiler.cmake" to
save information detected about the system and compilers in use. The
method of detection and the exact results store varies across CMake
versions as things improve. This leads to problems when loading files
configured by a different version of CMake. Previously we ignored such
existing files only if the major.minor part of the CMake version
component changed, and depended on the CMakeCache.txt to tell us the
last version of CMake that wrote the files. This led to problems if the
user deletes the CMakeCache.txt or we add required information to the
files in a patch-level release of CMake (still a "feature point" release
by modern CMake versioning convention).
Ensure that we always have version-consistent platform information files
by storing them in a subdirectory named with the CMake version. Every
version of CMake will do its own system and compiler identification
checks even when a build tree has already been configured by another
version of CMake. Stored results will not clobber those from other
versions of CMake which may be run again on the same tree in the future.
Loaded results will match what the system and language modules expect.
Rename the undocumented variable CMAKE_PLATFORM_ROOT_BIN to
CMAKE_PLATFORM_INFO_DIR to clarify its purpose. The new variable points
at the version-specific directory while the old variable did not.
Several more recent Visual Studio Express editions are now available and
they support debug builds. Simplify our VS platform files by removing
support for these old tools. If anyone still uses them we can restore
support with a more modern way to test for them.
Ancient versions of CMake required else(), endif(), and similar block
termination commands to have arguments matching the command starting the
block. This is no longer the preferred style.
Run the following shell code:
for c in else endif endforeach endfunction endmacro endwhile; do
echo 's/\b'"$c"'\(\s*\)(.\+)/'"$c"'\1()/'
done >convert.sed &&
git ls-files -z -- bootstrap '*.cmake' '*.cmake.in' '*CMakeLists.txt' |
egrep -z -v '^(Utilities/cm|Source/kwsys/)' |
egrep -z -v 'Tests/CMakeTests/While-Endwhile-' |
xargs -0 sed -i -f convert.sed &&
rm convert.sed
Since commit c198730b (Detect Watcom compiler version with its id,
2011-12-07) the CMAKE_(C|CXX)_COMPILER_VERSION variables are set for the
Watcom compiler. Use these in Windows-wcl386.cmake to set the old
WATCOM1* version variables. This avoids using the old EXECUTE_PROCESS
command which failed due to extra quotes anyway.
Teach CMake to prefer the system default compiler automatically when no
compiler is specified. By default use "cc" for C, "CC" for C++, and
"f95" for Fortran. Load a new Platform/<os>-<lang>.cmake module to
allow each platform to specify for each language its system compiler
name(s) and/or exclude certain names.
Create Platform/(CYGWIN|Darwin|Linux|Windows)-CXX.cmake modules to
specify "c++" as the system C++ compiler name for these platforms. On
systems that use case-insensitive filesystems exclude C++ compiler names
that are distinguished from C compiler names only by case.
This will change the default compiler selection for existing build
scripts that do not specify a compiler when run on machines with
separate system and GNU compilers both installed in the PATH. We do not
make this change in default behavior lightly. However:
(1) If a given build really needs specific compilers one should specify
them explicitly e.g. by setting CC, CXX, and FC in the environment.
(2) The motivating case is to prefer the system Clang on newer OS X
systems over the older GNU compilers typically also installed. On
such systems the names "cc" and "c++" link to Clang. This is the
first platform known to CMake on which "c++" is not a GNU compiler.
The old behavior selected "gcc" for C and "c++" C++ and therefore
chooses GNU for C and Clang for C++ by default. The new behavior
selects GNU or Clang consistently for both languages on older or
newer OS X systems, respectively.
(3) Other than the motivating OS X case the conditions under which the
behavior changes do not tend to exist in default OS installations.
They typically occur only on non-GNU systems with manually-installed
GNU compilers.
(4) The consequences of the new behavior are not dire. At worst the
project fails to compile with the system compiler when it previously
worked with the non-system GNU compiler. Such failure is easy to
work around (see #1).
In short this change creates a more sensible default behavior everywhere
and fixes poor default behavior on a widely-used platform at the cost of
a modest change in behavior in less-common conditions.
4bb94c9 Ninja: sysconf() is declared in unistd.h
bb36759 Ninja: enable response file support on Mac (length 262144)
3a2c8e8 Ninja: disable work around when linking with mingw
3856e66 Ninja: error on missing rspfile_content
8c1e35c Ninja: remove some unused default arguments
7f647cf Ninja: also write link libraries to rsp file
The work around is only needed by older GCCs (only testet 4.4/4.7)
Ninja is very new so chances are high that there is also a new mingw.
Use slashes in link rsp file, because ar.exe can't handle \.
Among other flags this sets RPATH flags correctly so that CMake knows
how to treat CMAKE_PLATFORM_REQUIRED_RUNTIME_PATH for the ASM language.
This is the GNU compiler equivalent to commit a0bab7ae (Add ASM platform
information for XL compiler on AIX, 2011-03-02), made for XL.
bd34963 Refactor generation of shared library flags
55d7aa4 Add platform variable for flags specific to shared libraries
31d7a0f Add platform variables for position independent code flags
Store in new platform variables
CMAKE_${lang}_COMPILE_OPTIONS_PIC
CMAKE_${lang}_COMPILE_OPTIONS_PIE
flags for position independent code generation.
In almost all cases, this means duplication of the
CMAKE_SHARED_LIBRARY_${lang}_FLAGS for the _PIC case and using the
assumed pie equivalent for the _PIE case. Note that the GNU compiler
has supported -fPIE since 3.4 and that there is no -fPIC on GNU for
Windows or Cygwin.
There is a possibility that the _PIE variables are not correct.
However, as there is no backwards compatibility to be concerned about
(as the POSITION_INDEPENDENT_CODE property is not used anywhere yet),
the current state suffices.
The default for `CMAKE_FIND_FRAMEWORK`, defined in `Darwin.cmake` and
`Darwin-icc.cmake`, is now guarded so that it will not override command line
arguments passed by users.
Similarly for `CMAKE_FIND_APPBUNDLE`
Add a boolean target property NO_SONAME which may be used to disable
soname for the specified shared library or module even if the platform
supports it. This property should be useful for private shared
libraries or various plugins which live in private directories and have
not been designed to be found or loaded globally.
Replace references to <CMAKE_SHARED_LIBRARY_SONAME_${LANG}_FLAG> and
hard-coded -install_name flags with a conditional <SONAME_FLAG> which is
expanded to the value of the CMAKE_SHARED_LIBRARY_SONAME_${LANG}_FLAG
definition as long as soname supports is enabled for the target in
question. Keep expanding CMAKE_SHARED_LIBRARY_SONAME_${LANG}_FLAG in
rules in case third party projects still use it. Such projects would
not yet use NO_SONAME so the adjacent <TARGET_SONAME> will always be
expanded. Make <TARGET_INSTALLNAME_DIR> NO_SONAME aware as well. Since
-install_name is soname on OS X, this should not be a problem if this
variable is expanded only if soname is enabled.
The Ninja generator performs rule variable substitution only once
globally per rule to put its own placeholders. Final substitution is
performed by ninja at build time. Therefore we cannot conditionally
replace the soname placeholders on a per-target basis. Rather than
omitting $SONAME from rules.ninja, simply do not write its contents for
targets which have NO_SONAME. Since 3 variables are affected by
NO_SONAME ($SONAME, $SONAME_FLAG, $INSTALLNAME_DIR), set them only if
soname is enabled.
Use of the deprecated option with Intel 2011 produces
icl: command line remark #10010: option '/GX' is deprecated and will
be removed in a future release. See '/help deprecated'
so use its replacement option which has been supported for several
older versions anyway.
The parent commit added a search path relative to OSX_DEVELOPER_ROOT.
But with Xcode 4.3 the nested Applications folder is in a different
relative location compared to that root. This commit makes the intent
of the previous commit work with older and newer Xcode directory layouts.
Furthermore, it only adds paths that exist to the search path.
Since commit 4693cf84 (Xcode: Detect new default locations of Xcode 4.3
bits and pieces) Darwin.cmake detects the developer application
directory instead of hard-coding /Developer. Replace the hard-coded
path in CMAKE_SYSTEM_APPBUNDLE_PATH using the computed result.
0f4dfa6 CPack: Use real path to PackageMaker to find its version file (#12621)
4693cf8 Xcode: Detect new default locations of Xcode 4.3 bits and pieces (#12621)
8485208 Ninja: shell escape $(CMAKE_SOURCE_DIR) and $(CMAKE_BINARY_DIR)
df84767 Ninja: add support for OBJECT_OUTPUTS, fix PrecompiledHeader test case
48eb7fc Ninja: Avoid using 'this' in member initializers
bba37dd Ninja: Fix for PDB files with spaces in the path.
ac800f4 Ninja: Constify use of cmCustomCommand
9a0d5a8 Ninja: add /DEF: flag to linker call
d40eebd Ninja: Add a cache option CMAKE_ENABLE_NINJA to enable the ninja generator.
8c63433 Ninja: Add friend struct so it can access the private ConvertToNinjaPath.
dbe3dce Ninja: add .def file support
f1bb08f Ninja: ensure the output dir exists at compile time
7a6b5f4 Ninja: Remove an unnecessary variable
80ff210 Ninja: Use cmSystemTools::ExpandListArgument to split compile/link commands
d2731a3 Ninja: Add a missed license header
eabc9b0 Ninja: CMake: Adapt Ninja generator for per-target include dirs
bada88e Merge branch 'target-include-directories' into ninja-generator
54bd175 Ninja: windows msvc: create for each target a .pdb file
...
Xcode 4.3 installs into "/Applications" by default, from the Mac App Store.
Also, the paths to the available SDKs changed: they are now within the
Xcode.app bundle.
PackageMaker is installed as a separate program, and may be installed
anywhere. It is not installed with Xcode 4.3 by default anymore.
Download the "Auxiliary Tools for Xcode" to get PackageMaker.
Put PackageMaker inside the Xcode.app bundle, in its nested Applications
folder, or put it alongside Xcode in "/Applications" and CMake will find
it.
Update references to "find" paths: add new possible locations for finding
Xcode.app and PackageMaker.app. Prefer the most recent version's locations
first, but keep the old locations as fallback search paths, too.
Thanks to all the contributors who provided and tested out various patches
for fixing this issue. Especially, but by no means limited to:
Francisco Requena Espí, Jamie Kirkpatrick and drfrogsplat.
The Borland compiler was re-branded as CodeGear during 2007-2009 and
since 2009 is the Embarcadero compiler. They offer predefined macros:
http://docwiki.embarcadero.com/RADStudio/en/Predefined_Macros
and distinguish themselves by __CODEGEARC__ and __CODEGEARC_VERSION__.
Version 6.30 (C++Builder XE) changed the meaning of some flags:
http://docwiki.embarcadero.com/RADStudio/en/C%2B%2B_Compiler_Option_Changes_for_XE
Teach Embarcadero compiler information files to generate build rules
with flags matching the compiler version. Leave the flags unchanged
for old Borland versions. Always set the BORLAND toolchain indicator
for compatibility with existing projects that test it. Also set the
EMBARCADERO indicator for newer toolchains.
The Borland compiler is now the Embarcadero compiler. Rename the shared
platform information file to reflect this. This does not change the
interface, as old versions are still "Borland", but will allow new
versions released by Embarcadero to be supported cleanly.
Fix typo introduced in commit 66a08c10 (more uniform approach to enable
language, 2004-08-26). The optimization option should be /O2 for
Release configurations and /O1 for MinSizeRel.
Suggested-by: He Yuqi <yuqi.he@gmail.com>
The default OS X 10.4 linker incorrectly searches for dependencies of
linked shared libraries only under the -isysroot location. It fails to
find dependencies of linked shared libraries in cases such as the
ExportImport test. It produces errors like:
/usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: warning can't open dynamic library:
libtestLib3Imp.dylib
referenced from: /.../ExportImport/Root/lib/libtestLib3lib.1.2.dylib
(checking for undefined symbols may be affected) (No such file or directory, errno = 2)
/usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: Undefined symbols: _testLib3Imp
referenced from libtestLib3lib expected to be defined in
libtestLib3Imp.dylib
or with CMAKE_SKIP_RPATH off to enable install_name in the Export side:
/usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: warning can't open dynamic library:
/Developer/SDKs/MacOSX10.4u.sdk/.../ExportImport/Export/impl/libtestLib3Imp.dylib
referenced from: /.../ExportImport/Export/libtestLib3lib.1.2.dylib
(checking for undefined symbols may be affected) (No such file or directory, errno = 2)
/usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: Undefined symbols:_testLib3Imp
referenced from libtestLib3lib expected to be defined in
/.../ExportImport/Export/impl/libtestLib3Imp.dylib
Note how "/Developer/SDKs/MacOSX10.4u.sdk" is prepended to the dependent
library path.
Commit 2cff26fa (Support linking to shared libs with dependent libs,
2008-01-31) and commit 82fcaebe (Pass dependent library search path to
linker on some platforms, 2008-02-01) worked around the problem by
defining platform variable CMAKE_LINK_DEPENDENT_LIBRARY_FILES. It tells
CMake to link to dependent libraries explicitly by their path thus
telling the linker where to find them.
Unfortunately the workaround had the side effect of linking dependent
libraries and defeats most benefits of LINK_INTERFACE_LIBRARIES.
Fortunately OS X 10.5 and above do not need to find transitive
dependencies at all so we can avoid the workaround on Modern OS X.
Previously we linked C, Fortran, and ASM shared libraries compiled with
the HP compiler using a direct invocation of the linker (ld). This
behavior was left historically from support for an ancient HP C compiler
that did not know how to create shared libraries. Fortran shared
libraries need to be linked with the compiler to get the language
runtime library dependencies as is already done for C++.
Update the HP-UX-HP* platform information to use the compiler front end
when linking shared libraries. This works on modern HP tools and
produces correct behavior. If there is a need to support older tools
again we can add a special case for them.
ae62a1c Test CMAKE_GNUtoMS option in ExportImport on MinGW and MSys
afb00fe Add CMAKE_GNUtoMS option to convert GNU .dll.a to MS .lib
61e8629 Factor makefile generator link rule lookup into helper function
a603250 Load platform files that need to know the ABI when possible
ecd8414 Fortran: Detect pointer size in gfortran on MinGW
Teach the Windows-GNU.cmake platform file to look for Visual Studio
tools matching the target ABI. Add an extra step to the link command
for shared libraries and executables that export symbols and on which a
new GNUtoMS property is set (initialized by the CMAKE_GNUtoMS option).
Tell the GNU linker to output a module definition (.def) file listing
exported symbols in addition to the GNU-format import library (.dll.a).
Pass the .def file to the MS "lib" tool to construct a MS-format DLL
import library (.lib).
Teach the install(TARGETS) command to install the MS import library next
to the GNU one. Teach the install(EXPORT) and export() command to set
the IMPORTED_IMPLIB property pointing at the import library to use the
import library matching the tools in the importing project.
Use __SIZEOF_POINTER__ which the GNU Fortran compiler defines at least
on 64-bit MinGW. Assume default size 4 on MinGW if gfortran does not
define the size.
Use the "-shared" option to link shared libraries. The compiler does
not support "-Wl," or "-rpath" but does know how to pass "-soname"
through to the linker.
- Build wasn't properly using -soname linker args, so installed libraries
could depend on relative paths from the build directory.
- Consolidated GNU linker args to one place in the BlueGeneP-base platform
file, since ld is used by both XL and GNU toolchains on BlueGene.
Commit 6d434ee6 (Split XL compiler information files, 2009-09-30)
added Platform/AIX-(XL|VisualAge)-(C|CXX|Fortran).cmake modules
to support the old and new compiler branding for all languages.
Add the "AIX-VisualAge-Fortran" combination that was left out
accidentally.
Allows wlib to generate proper exports if two routines have
the same spelling, but different case (like Scale and scale).
Thanks to J Decker for the patch.
* Fix linux CMAKE_LIBRARY_ARCHITECTURE_REGEX to support armel-linux-gnueabi.
* Add CMAKE_LIBRARY_ARCHITECTURE_REGEX on kFreeBSD.
* Add CMAKE_LIBRARY_ARCHITECTURE_REGEX on GNU (Hurd).
Also regex is improved to support quadlets. Even if I have not seen this
in the wild yet, reportedly they are possible.
Implement support for multiarch as specified here:
http://wiki.debian.org/Multiarchhttps://wiki.ubuntu.com/MultiarchSpec
Detect the <arch> part of <prefix>/lib/<arch> from the implicit library
search path from each compiler to set CMAKE_<lang>_LIBRARY_ARCHITECTURE.
Define CMAKE_LIBRARY_ARCHITECTURE using one of these values (they should
all be the same). Teach the find_library and find_package commands to
search <prefix>/lib/<arch> whenever they would search <prefix>/lib.
8bd3e51 Absoft: Enable FortranCInterface check in Fortran test
d7b376b Absoft: Detect implicit link libraries on Linux and Mac
ac5b999 Add Absoft Fortran compiler id and basic flags
Use the "-X -v" flag to the Absoft front-end to pass "-v" to the gcc it
invokes under the hood. Teach CMakeParseImplicitLinkInfo to exclude
linker version lines from consideration as link lines. Fix parsing of
Sun's linker search path option "-Y..." to avoid conflict with the Mac
linker option "-Y<num>".
86cb17b Pass include directories with response files to GNU on Windows
9a0b9bc Optionally pass include directories with response files
6e8a67f Generate target-wide flags before individual build rules
d099546 Factor old-style -D flags out from -I flag generation
The GNU 4.x toolchain on MinGW (and therefore MSYS) allows compiler
options to be passed via response files. Use this to pass include
directory -I options. This allows the include file search path to be
very long despite shell and mingw32-make command line length limits.
Move HP flags out of Platform/HP-UX.cmake into platform-specific
compiler information files "Platform/HP-UX-HP-<lang>.cmake". Factor
common values into "Platform/HP-UX-HP.cmake" and load it from the
per-language files.
Move RPATH flags out of Platform/AIX.cmake into platform-specific
compiler information files Platform/AIX-XL and Platform/AIX-GNU.
The flags need to be set for each compiler of each language.
Commit 6a61a8a5 (Honor module .def files with MinGW tools, 2011-02-21)
set CMAKE_LINK_DEF_FILE_FLAG to "-Wl," to enable passing .def files to
the linker on MinGW. However, older GNU tools in the MSYS shell do not
know how to translate "-Wl,/c/..." to "c:/..." and complain that the
file does not exist. Instead set the flag to just "" which tells CMake
it can pass the file through the front-end with no special flag.
Since commit 024d05ad (Fix use of module .def files for MS tools,
2009-09-29) module .def files work for any platform that sets
CMAKE_LINK_DEF_FILE_FLAG correctly. Set it in the Windows-GNU platform
information file to enable support with MinGW tools. Also enable the
test added by commit 0db2c850 (Test use of module .def files for MS
tools, 2009-09-29) for MinGW and MSYS generators.