FIXME: llvm/test may be aware of LLVM_PLUGIN_EXT, like as clang/test does.
FIXME: CMAKE_*_SUFFIX may be set in HandleLLVMOptions if those variables could be writable, rather than to set one as target properties.
llvm-svn: 201316
I was insightless then about unknown optional parameters.
(Consider that LINK_LIBS foo bar ADDITIONAL_HEADERS qux quux)
Suggested by Michael Kruse. Thanks!
llvm-svn: 201283
This macro depends on several variables to be set in the calling
context. Check them and report an error if they are not set.
Without this, custom commands may be silently specified that
will fail at build time.
Patch by Brad King.
llvm-svn: 201229
- MODULE;SHARED;STATIC
STATIC by default w/o BUILD_SHARED_LIBS.
SHARED by default w/ BUILD_SHARED_LIBS.
- OUTPUT_NAME name
Corresponds to OUTPUT_NAME in target properties.
- DEPENDS targets...
Same semantics as add_dependencies().
- LINK_COMPONENTS components...
Same as the variable LLVM_LINK_COMPONENTS.
- LINK_LIBS lib_targets...
Same semantics as target_link_libraries().
- ADDITIONAL_HEADERS (implemented in LLVMProcessSources)
May specify header files for IDE generators.
I suggest llvm_add_library() may be used for inter-project add_library stuff
and also suggest add_***_library() may be used project-specific.
Please be patient that llvm_add_library might be ambiguous against add_llvm_library.
llvm-svn: 201072
I am sure it'd not be required any more.
In trunk, all of tablegen's users depend on ${TABLEGEN_OUTPUT} as not file dependency but inter-target dependency.
llvm-svn: 201063
CMake's target_link_libraries() will manage dependencies with Brad's LLVMConfig improvements.
Configuration time may be reduced by a few seconds.
llvm-svn: 201062
Teach the Makefile build system to generate and install CMake modules
LLVMConfig.cmake and LLVMConfigVersion.cmake so that applications that
build with CMake can use 'find_package(LLVM)' even when LLVM is not
built with CMake. These modules tell such applications about available
LLVM libraries and their dependencies.
Run llvm-config to generate the list of libraries and use the results of
llvm-build to generate the library dependencies. Use sed to perform
substitutions in the LLVMConfig.cmake.in and LLVMConfigVersion.cmake.in
sources that our CMake build system uses.
Teach the Makefile build system to generate the LLVMExports.cmake file
with content similar to that produced by the CMake install(EXPORT)
command. Extend llvm-build with an option to generate the library
dependencies fragment for this file.
Contributed by Brad King.
llvm-svn: 201053
Teach each package configuration file to load the LLVMExports file for
its corresponding tree. This will allow application CMake code to use
logical library and executable target names from LLVM as if they were in
our own build process (e.g. LLVMSupport). CMake will have enough
information to propagate LLVM library link dependencies automatically
while configuring applications.
Contributed by Brad King.
llvm-svn: 201051
Record every logical target that we install with install(TARGETS) in a
global LLVM_EXPORTS property. Then use the export(TARGETS) command to
provide a "LLVMExports.cmake" file that exports logical targets for
import into applications directly from our build tree.
The "LLVMExports.cmake" file is not meant for direct inclusion by
application code but should be included by "LLVMConfig.cmake" in a
future change.
Contributed by Brad King.
llvm-svn: 201050
Use the install(TARGETS) command EXPORT option for every library and
executable that we install with LLVM. Then use the install(EXPORT)
command to provide a "LLVMExports.cmake" file that exports logical
targets for import into applications from our install tree.
The "LLVMExports.cmake" file is not meant for direct inclusion by
application code but should be included by "LLVMConfig.cmake" in a
future change.
Contributed by Brad King.
llvm-svn: 201049
Create separate package configuration files "LLVMConfig.cmake" for the
LLVM build and install trees so that each can have information specific
to its tree. Configure each with the corresponding include, lib, and
cmake directories. Include the "LLVM-Config" API modules directly from
the configured cmake modules directory.
In the install tree, compute the installation prefix relative to the
file location. In the build tree, provide information specific to the
build tree for use by tools like Clang that can build externally against
the LLVM build tree. Prefix such values in "LLVM_BUILD_" and comment
them as such.
Contributed by Brad King.
llvm-svn: 201048
Do not modify this value on the application's behalf and just ensure API
modules are always available next to the LLVMConfig module. This is
already the case in the install tree so use file(COPY) to make it so in
the build tree. Include the LLVM-Config API module from next to the
LLVMConfig location.
Contributed by Brad King.
llvm-svn: 201047
CMake won't expand the dependency graph for us if the dependencies are in
another project, which leads to link errors in the standalone build.
This is a refinement of r200765.
llvm-svn: 200812
r200744 moved this into cmake/config-ix.cmake, so that it would happen very
early in the build process. However, standalone builds of Clang and other
external projects never include this file (which is correct).
Now, -stdlib=libc++ and the LLVM_COMPILER_IS_GCC_COMPATIBLE option are
both set in a new include file, HandleLLVMStdlib, which is included by
both config-ix.cmake and HandleLLVMOptions.cmake. This preserves existing
behavior for projects relying on HandleLLVMOptions and still does the
right thing for builds of LLVM itself.
llvm-svn: 200811
In trunk, every users assume add_llvm_loadable_module as "loadable module" and no one sets neither SHARED, ... nor also MODULE!
Unfortunately, all loadable modules were linked as not "MODULE" but "SHARED".
If this change caused any regressions, I wish guys to fix it properly. ;)
llvm-svn: 200762
If LLVM_ENABLE_LIBCXX is specified, we should append -stdlib=libc++ to build
flags as early as possible, in particular, before we check for header presence
(as -stdlib=libc++ modifies header lookup rules). Otherwise we can find a header
at configure time (w/o -stdlib=libc++) but fail to find it at build time
(with -stdlib=libc++). See PR18569 for more details.
llvm-svn: 200744
It missed include/llvm/Target. Could I avoid GLOB_RECURSE anyways? :(
FYI, I intended to prune ${LLVM_MAIN_INCLUDE_DIR} in TableGen.cmake in r200150.
llvm-svn: 200730
LLVM_REQUIRES_EH implies LLVM_REQUIRES_RTTI. It is as same behavior as Makefile.rule's.
llvm/examples/ExceptionDemo is affected. (It was built with -fno-rtti.)
For MSVC, Remove flags like "/EHsc /GR" in HandleLLVMOptions, or CL.EXE complains with flags like "/GR /GR-".
llvm_update_compile_flags() updates source file property if the target contains *.c.
COMPILE_FLAGS in target properties affects both C++ and C!
LLVM_NO_RTTI is deprecated. It was introduced by me and was my mistake.
llvm-svn: 200301
With this tweaks, also unittests are compiled with -ffunction-sections.
It's hard to control contextual CMAKE_CXX_FLAGS. We should get rid of twiddling it as possible.
llvm-svn: 200299
ADDITIONAL_HEADERS is intended to add header files for IDEs as hint.
For example:
add_llvm_library(LLVMSupport
Host.cpp
ADDITIONAL_HEADERS
Unix/Host.inc
Windows/Host.inc
)
llvm-svn: 199639
In LLVM build tree, they points corresponding INTDIR.
In Clang standalone tree, they points external dir (llvm-config's --bindir and --libdir).
llvm-svn: 199595
accidentally pick that up while using Clang and run into subtle bugs
down the road related to C++11 features not fully implemented in that
version of the standard library.
llvm-svn: 199484
The generation of the native_export_file end up in
several different makefiles. All those makefiles
write the same file, but can be executed concurrently...
and bad things happen!
llvm-svn: 199356
option with the others in the top level CMakeLists, and put the check in
HandleLLVMOptions. This will also let it be used from the standalone
Clang builds.
llvm-svn: 199149
This is needed to support the addition of tests for clang loadable plugins.
In clang, plugins are built as modules (bundles on OS X) rather than dynamic
libraries (dylib) so the build system needs to inform lit of the actual
file extension in use, typically '.so' on Unix and '.dll' on Windows.
(LLVM itself should probably switch to this scheme to fix PR14903 once and for
all.)
No change in build output or functionality intended.
llvm-svn: 198746
Summary:
This parameter is required to build C++11 projects (like lld or lldb) on OS X as the default STL does not provide c++ classes.
CC: llvm-commits, triton
Differential Revision: http://llvm-reviews.chandlerc.com/D2381
llvm-svn: 198625
Plugins need to go in build/Debug/lib as well (rather than build/lib/Debug).
Also, fix the SHLIBDIR path for Xcode, which by default includes Xcode build
settings rather than a simple %(build_mode)s parameter.
llvm-svn: 198344
We have been seeing nasty directory layout with CMake multiconfig, such as,
bin/Release/clang.exe
lib/clang/3.x/...
lib/Release/clang/3.x/.. (duplicated)
Move the layout similar to autoconf's;
Release/bin/clang.exe
Release/lib/clang/3.x/...
Checked on Visual Studio 10. Could you guys please confirm my change on XCode(and other multiconfig builders)?
Note: Don't set variables CMAKE_*_OUTPUT_DIRECTORY any more, or a certain builder, for eaxample, msbuild.exe, would be confused.
llvm-svn: 198205
The windows ninja build is now green, but msvs is still unhappy. Maybe that's
because the .def file was passed when building LTO_static, so only pass
symbol lists for shared libraries.
llvm-svn: 198151
The command that cmd.exe is complaining about is:
cmd.exe /c cd /D C:\bb-win7\cmake-clang-i686-mingw32\build\tools\lto && cmake -E echo EXPORTS > symbol.def && type C:/bb-win7/cmake-clang-i686-mingw32/llvm-project/llvm/tools/lto/lto.exports >> symbol.def
Maybe quoting the filename helps.
llvm-svn: 198140
The cmake build didn't support EXPORTED_SYMBOL_FILE. Instead, it had a
Windows-only implementation in tools/lto/CMakeLists.txt, a linux-only
implementation in tools/gold/CMakeLists.txt, and a darwin-only implementation
in tools/clang/tools/libclang/CMakeLists.txt.
This attempts to consolidate these one-offs into a single place. Clients can now
just set LLVM_EXPORTED_SYMBOL_FILE and things (hopefully) Just Work, like in
the make build.
llvm-svn: 198136
This changes Clang standalone builds so that clang-tblgen lives in
clang/build/bin instead of llvm/build/bin, and so that with the Xcode
generator it's in clang/build/bin/Debug instead of llvm/build/bin/Debug/Debug/.
Yes, really.
llvm-svn: 197590
I think, in principle, intrinsics_gen may be added explicitly.
That said, it can be added incidentally, since each target already has dependencies to llvm-tblgen.
Almost all source files depend on both CommonTaleGen and intrinsics_gen.
Explicit add_dependencies() have been pruned under lib/Target.
llvm-svn: 195929
add_public_tablegen_target adds *CommonTableGen to LLVM_COMMON_DEPENDS.
LLVM_COMMON_DEPENDS affects add_llvm_library (and other add_target stuff) within its scope.
llvm-svn: 195927
In some case, it may be required to build LLVM in C++11 mode, as some the subprojects (like lldb) requires it.
This mimics the autoconf behaviour.
However, given the discussions on the switch to C++11 of the codebase, this behaviour should evolve to default to C++11 with some checks of the compiler capabilities.
llvm-svn: 195727
for release builds.
This is a follow-up to r194589. Aaron pointed out that building
libraries with /MT and using them in an application that uses a
different run-time library can be a bad idea.
Move the option to build with /MT behind a CMake option so it can be
turned on selectively, such as when building the toolchain installer.
llvm-svn: 194596
This should fix the problem of snapshot builds created with MSVC 2012 not
working for users with MSVC 2010, etc.
Differential Revision: http://llvm-reviews.chandlerc.com/D2157
llvm-svn: 194589
After r192904, Reid pointed out he thought we already set the stack
size for MSVC. Turns out we did, but it didn't seem to work.
This commit sets the stack size in a single place, using
CMAKE_EXE_LINKER_FLAGS because that seems to be the way that works
best.
llvm-svn: 192912
Compiling under Visual C++ 2012 with the default stack size of 1MB, the stack
overflows at a depth of 216 template instantiations, well before the 256
default limit. This patch modifies the default MSVC stack size to 2MB.
Patch by Yaron Keren!
llvm-svn: 192904
Summary:
The MSVCRT deliberately sends main() code-page specific characters.
This isn't too useful to LLVM as we end up converting the arguments to
UTF-16 and subsequently attempt to use the result as, for example, a
file name. Instead, we need to have the ability to access the Unicode
command line and transform it to UTF-8.
This has the distinct advantage over using the MSVC-specific wmain()
function as our entry point because:
- It doesn't work on cygwin.
- It only work on MinGW with caveats and only then on certain versions.
- We get to keep our entry point as main(). :)
N.B. This patch includes fixes to other parts of lib/Support/Windows
s.t. we would be able to take advantage of getting the Unicode paths.
E.G. clang spawning clang -cc1 would want to give it Unicode arguments.
Reviewers: aaron.ballman, Bigcheese, rnk, ruiu
Reviewed By: rnk
CC: llvm-commits, ygao
Differential Revision: http://llvm-reviews.chandlerc.com/D1834
llvm-svn: 192069
I got a report of a hang in git's helper functions trying to figure out
how to display results of "git svn info" when run inside ninja, even though
the result is immediately piped to grep. This seems to avoid that.
llvm-svn: 190808
This allows the logic to work with Git, and also uses the variable names
to match what Clang is actually looking for.
This changes the interface of GetSVN.cmake. Clang change to follow.
llvm-svn: 190556
It was removed in r189130, but it turns out this makes life hard for
folks packaging LLVM and Clang and building the latter based on the
LLVM package.
Note that this only adds back the LLVM tblgen, and it's obviously
not included when LLVM_INSTALL_TOOLCHAIN_ONLY is set.
llvm-svn: 190419
Xcode always puts executable targets in the directory
bin/<Config>. When building separate LLVM and Clang projects for
Xcode, this prevents the CMake-configured project for Clang from
finding llvm-tblgen. Add a symlink so that tblgen executables are
always available in bin/ (regardless of the configuration LLVM is
built with).
llvm-svn: 189220
Allow CMake to pick up external projects in llvm/tools without the need to modify the "llvm/tools/CMakeLists.txt" file.
This makes it easier to work with projects that live in other repositories, without needing to specify each one in "llvm/tools/CMakeLists.txt".
llvm-svn: 188921
library for color support detection. This still will use a curses
library if that is all we have available on the system. This change
tries to use a smaller subset of the curses library, specifically the
subset that is on some systems split off into a separate library. For
example, if you install ncurses configured --with-tinfo, a 'libtinfo' is
install that provides just the terminfo querying functionality. That
library is now used instead of curses when it is available.
This happens to fix a build error on systems with that library because
when we tried to link ncurses into the binary, we didn't pull tinfo in
as well. =]
It should also provide an easy path for supporting the NetBSD
libterminfo library, but as I don't have access to a NetBSD system I'm
leaving adding that support to those folks.
llvm-svn: 188160
using it to detect whether or not a terminal supports colors. This
replaces a particularly egregious hack that merely compared the TERM
environment variable to "dumb". That doesn't really translate to
a reasonable experience for users that have actually ensured their
terminal's capabilities are accurately reflected.
This makes testing a terminal for color support somewhat more expensive,
but it is called very rarely anyways. The important fast path when the
output is being piped somewhere is already in place.
The global lock may seem excessive, but the spec for calling into curses
is *terrible*. The whole library is terrible, and I spent quite a bit of
time looking for a better way of doing this before convincing myself
that this was the fundamentally correct way to behave. The damage of the
curses library is very narrowly confined, and we continue to use raw
escape codes for actually manipulating the colors which is a much sane
system than directly using curses here (IMO).
If this causes trouble for folks, please let me know. I've tested it on
Linux and will watch the bots carefully. I've also worked to account for
the variances of curses interfaces that I could finde documentation for,
but that may not have been sufficient.
llvm-svn: 187874
The issue is that CMAKE_BUILD_TYPE=RelWithDebInfo LLVM_ENABLE_ASSERTIONS=ON was
not building with assertions enabled. (I was unable to find what in the LLVM
source tree was adding -DNDEBUG to the build line in this case, so decided that
it must be cmake itself that was adding it - this may depend on the cmake
version). The fix treats any mode that is not Debug as being the same as
Release for this purpose (previously it was being assumed that cmake would only
add -DNDEBUG for Release and not for RelWithDebInfo or MinSizeRel). If other
versions of cmake don't add -DNDEBUG for RelWithDebInfo then that's OK: with
this change you just get a useless but harmless -UNDEBUG or -DNDEBUG.
llvm-svn: 186499
to have them appear in the right order. Instead append all warnings explicitly
to the language flags. This was already the case for many warnings. Fixes the
issue of -Wno-maybe-uninitialized not being effective because -Wall was being
placed after it rather than before.
llvm-svn: 177866
CMake and autotools disagree on what "host" means in a cross-compilation
context. Autotools (and lit) take it to be the machine the binaries being
compiled now will run on. CMake takes it to be the machine actually compiling
the binaries now.
This change makes lit.site-cfg more consistent between autotools and CMake,
allowing lit tests (particularly in ExecutionEngine) to run correctly when
cross-compiled with CMake
llvm-svn: 175179
Added support to the cmake build to turn off uninitialized use warnings
for gcc. This cleans the build up somewhat.
Used logic simpler than found in autoconf by making use of the fact that
although gcc won't complain about unsupported -Wno-* flags it *will*
complain about unsupported -W flags.
Reviewers: gribozavr, doug.gregor, chandlerc
llvm-svn: 174299
catches uses of an extremely minor and widely-available C++ extension (which
every C++ compiler I could find supports, but EDG and Clang reject in strict
mode).
The diagnosed code pattern looks like this:
struct X {
union {
struct {
int a;
int b;
} S;
};
};
llvm-svn: 174103
gcc produces false positives for empty braces so turning the warning off.
Instead, turning the warning on for clang so proper warnings aren't missed.
Reviewers: dblaikie, chandlerc
llvm-svn: 174073
For example,
cur) unittests/ADT/Release/ADTTests
new) unittests/ADT/ADTTests
RUNTIME_BUILD_MODE can be substituted to CMAKE_CFG_INTDIR.
With Make and Ninja, the tree is not built with multiple configurations.
Then, including the build type in target directory doesn't make sense.
See also "How can I build multiple modes without switching?"
http://www.cmake.org/Wiki/CMake_FAQ
CMAKE_CFG_INTDIR is set to "."
With multiple-configuration-aware build system, like Visual Studio, each unittest is built on appropriate directory, for example,
unittests/ADT/Release/ADTTests.exe
CMAKE_CFG_INTDIR is set to build system's variable, like "$(Configuration)" or "$(OutDir)".
Thus, "--param build_config" is also deprecated.
llvm-svn: 173616
This warning fires on:
Operator::~Operator() {
llvm_unreachable("should never destroy an Operator");
}
That seems like a false positive. I don't see any good way to silence
the warning here, so I'm disabling it.
llvm-svn: 173455
wall time, user time, and system time since a process started.
For walltime, we currently use TimeValue's interface and a global
initializer to compute a close approximation of total process runtime.
For user time, this adds support for an somewhat more precise timing
mechanism -- clock_gettime with the CLOCK_PROCESS_CPUTIME_ID clock
selected.
For system time, we have to do a full getrusage call to extract the
system time from the OS. This is expensive but unavoidable.
In passing, clean up the implementation of the old APIs and fix some
latent bugs in the Windows code. This might have manifested on Windows
ARM systems or other systems with strange 64-bit integer behavior.
The old API for this both user time and system time simultaneously from
a single getrusage call. While this results in fewer system calls, it
also results in a lower precision user time and if only user time is
desired, it introduces a higher overhead. It may be worthwhile to switch
some of the pass timers to not track system time and directly track user
and wall time. The old API also tracked walltime in a confusing way --
it just set it to the current walltime rather than providing any measure
of wall time since the process started the way buth user and system time
are tracked. The new API is more consistent here.
The plan is to eventually implement these methods for a *child* process
by using the wait3(2) system call to populate an rusage struct
representing the whole subprocess execution. That way, after waiting on
a child process its stats will become accurate and cheap to query.
llvm-svn: 171551
"check-all" can be executed with 0 status, "check-all does nothing, no tools built."
LLVM_EXTERNAL_CLANG_BUILD=OFF LLVM_BUILD_TOOLS=OFF can reproduce this.
Oscar Fuentes reported this. Thank you.
llvm-svn: 171046
Adding CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG
C_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG
This is to handle the wackiness on a Mac host where cmake detects:
CMAKE_CXX_COMPILER == "/usr/bin/c++"
CMAKE_C_COMPILER == "/usr/bin/gcc"
llvm-svn: 168577
- Substitute hyphen to underscore, s/-/_/g, as the variable name.
- Additional parameter can be specified as the name of directory.
e.g.) add_llvm_external_project(clang-tools-extra extra)
- LLVM_EXTERNAL_CLANG_TOOLS_EXTRA_SOURCE_DIR=/path/to/llvm-srcroot/tools/clang/tools/extra, by default.
- Build directory is in ${CMAKE_CURRENT_BINARY_DIR}/extra
llvm-svn: 165311
in the abstraction for lit test suites so that the various other layers
of abstraction pick up the same behavioral fix, and so that we still get
a complete list of dependencies for the 'check-all' target.
This should fix the follow-on issues of the same nature with various
other build targets, including Clang targets. Sorry for the churn, and
again thanks to Matt for testing and breaking this more thoroughly.
llvm-svn: 159593
re-used. Also, build in direct support for accumulating a set of lit
parameters, arguments, and testsuites to run as part of a 'check-all'
rule. This sinks 'check-all' from a Clang-specific construct to
a generic construct of the project.
llvm-svn: 159482
Makefiles, the CMake files in every other part of the LLVM tree, and
sanity.
This should also restore the output tree structure of all the unit
tests, sorry for breaking that, and thanks for letting me know.
The fundamental change is to put a CMakeLists.txt file in the unittest
directory, with a single test binary produced from it. This has several
advantages:
- No more weird directory stripping in the unittest macro, allowing it
to be used more readily in other projects.
- No more directory prefixes on all the source files.
- Allows correct and precise use of LLVM's per-directory dependency
system.
- Allows use of the checking logic for source files that have not been
added to the CMake build. This uncovered a file being skipped with
CMake in LLVM and one in Clang's unit tests.
- Makes Specifying conditional compilation or other custom logic for JIT
tests easier.
It did require adding the concept of an explicit 'optional' source file
to the CMake build so that the missing-file check can skip cases where
the file is *supposed* to be missing. =]
This is another chunk of refactoring the CMake build in order to make it
usable for other clients like CompilerRT / ASan / TSan.
Note that this is interdependent with a Clang CMake change.
llvm-svn: 158909
facilities.
This was only used in one place in LLVM, and was used pervasively (but
with different code!) in Clang. It has no advantages over the standard
CMake facilities and in some cases disadvantages.
llvm-svn: 158889
This was previously only done for executables and shared libraries, but not
for modules. As modules are essentially shared libraries (that need to be
dlopened explicitly), threating them the same as shared libraries seems
reasonable. This fixes the LLVM_BUILD_32_BITS build of Polly.
Contributed by: Ondra Hosek <ondra.hosek@gmail.com>
llvm-svn: 158195
output. Peter Collingbourne also reports that it is showing up in
$(llvm-config --cflags).
Revert this for now since I don't know enough cmake to fix it properly.
This reverts commit 18efed7adc79c1970f307bb5b015d199012ba872.
llvm-svn: 156392
While making lld build under the tools directory I decided to refactor how this
works.
There is now a macro, add_llvm_external_project, which takes the name of the
expected subdirectory. This sets up two CMake options.
* LLVM_EXTERNAL_${NAME}_SOURCE_DIR
This is the path to the source. It defaults to
${CMAKE_CURRENT_SOURCE_DIR}/${name}.
* LLVM_EXTERNAL_${NAME}_BUILD
Enable and disable building the tool as part of LLVM.
I chose LLVM_EXTERNAL_${NAME} as a prefix so they all show up together in the
GUI.
llvm-svn: 155654
Clang builds. The detection logic for compilers that support the warning
isn't working. Rafael is going to investigate it, but didn't want people
to have to wade through build spam until then.
llvm-svn: 151649
This is useful for clients that want to maintain compatibility
across multiple releases of LLVM. Currently users like Klee and
Mesa all have to roll their own 'parse llvm-config --version
output and generate defines' solution.
Also reuse the new macros so that version information is less
redundant/likely to fall out of sync again in the future.
llvm-svn: 150405
dealing in the host triple, be honest about it and document the decision
to default the target triple to the host triple unless overridden.
llvm-svn: 148822
CMake versions 2.8.4 and earlier were giving this error since r146323:
"string end index: -1 is out of range 0 - 6"
Passing -1 as the length of the desired substring was a new feature
added in CMake 2.8.5:
http://www.cmake.org/Bug/view.php?id=10740
llvm-svn: 146372
