Author: hans Date: Fri Feb 8 03:06:27 2019 New Revision: 353512 URL: http://llvm.org/viewvc/llvm-project?rev=353512&view=rev Log: Merging r351387, r351765, and r353374:
------------------------------------------------------------------------ r351387 | jfb | 2019-01-16 23:22:38 +0100 (Wed, 16 Jan 2019) | 7 lines [NFC] Factor out + document build requirements Summary: This change factors out compiler checking / warning, and documents LLVM_FORCE_USE_OLD_TOOLCHAIN. It doesn't introduce any functional changes nor policy changes, these will come late. Subscribers: mgorny, jkorous, dexonsmith, llvm-commits Differential Revision: https://reviews.llvm.org/D56799 ------------------------------------------------------------------------ ------------------------------------------------------------------------ r351765 | jfb | 2019-01-22 00:53:52 +0100 (Tue, 22 Jan 2019) | 24 lines Document toolchain update policy Summary: Capture the current agreed-upon toolchain update policy based on the following discussions: - LLVM dev meeting 2018 BoF "Migrating to C++14, and beyond!" llvm.org/devmtg/2018-10/talk-abstracts.html#bof3 - A Short Policy Proposal Regarding Host Compilers lists.llvm.org/pipermail/llvm-dev/2018-May/123238.html - Using C++14 code in LLVM (2018) lists.llvm.org/pipermail/llvm-dev/2018-May/123182.html - Using C++14 code in LLVM (2017) lists.llvm.org/pipermail/llvm-dev/2017-October/118673.html - Using C++14 code in LLVM (2016) lists.llvm.org/pipermail/llvm-dev/2016-October/105483.html - Document and Enforce new Host Compiler Policy llvm.org/D47073 - Require GCC 5.1 and LLVM 3.5 at a minimum llvm.org/D46723 Subscribers: jkorous, dexonsmith, llvm-commits Differential Revision: https://reviews.llvm.org/D56819 ------------------------------------------------------------------------ ------------------------------------------------------------------------ r353374 | jfb | 2019-02-07 06:20:00 +0100 (Thu, 07 Feb 2019) | 12 lines Bump minimum toolchain version Summary: The RFC on moving past C++11 got good traction: http://lists.llvm.org/pipermail/llvm-dev/2019-January/129452.html This patch therefore bumps the toolchain versions according to our policy: llvm.org/docs/DeveloperPolicy.html#toolchain Subscribers: mgorny, jkorous, dexonsmith, llvm-commits, mehdi_amini, jyknight, rsmith, chandlerc, smeenai, hans, reames, lattner, lhames, erichkeane Differential Revision: https://reviews.llvm.org/D57264 ------------------------------------------------------------------------ Modified: llvm/branches/release_80/ (props changed) llvm/branches/release_80/CMakeLists.txt llvm/branches/release_80/cmake/modules/CheckCompilerVersion.cmake llvm/branches/release_80/docs/CMake.rst llvm/branches/release_80/docs/DeveloperPolicy.rst llvm/branches/release_80/docs/GettingStarted.rst Propchange: llvm/branches/release_80/ ------------------------------------------------------------------------------ --- svn:mergeinfo (original) +++ svn:mergeinfo Fri Feb 8 03:06:27 2019 @@ -1,3 +1,3 @@ /llvm/branches/Apple/Pertwee:110850,110961 /llvm/branches/type-system-rewrite:133420-134817 -/llvm/trunk:155241,351325,351344-351345,351349,351351,351370,351381,351421,351426,351436,351475,351485,351753-351754,351910,351930,351932,352034,352204,352246,352374,352555,352770,352889,352945,353082,353155,353218,353304,353367 +/llvm/trunk:155241,351325,351344-351345,351349,351351,351370,351381,351387,351421,351426,351436,351475,351485,351753-351754,351765,351910,351930,351932,352034,352204,352246,352374,352555,352770,352889,352945,353082,353155,353218,353304,353367,353374 Modified: llvm/branches/release_80/CMakeLists.txt URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_80/CMakeLists.txt?rev=353512&r1=353511&r2=353512&view=diff ============================================================================== --- llvm/branches/release_80/CMakeLists.txt (original) +++ llvm/branches/release_80/CMakeLists.txt Fri Feb 8 03:06:27 2019 @@ -383,9 +383,12 @@ option(LLVM_ENABLE_EXPENSIVE_CHECKS "Ena set(LLVM_ABI_BREAKING_CHECKS "WITH_ASSERTS" CACHE STRING "Enable abi-breaking checks. Can be WITH_ASSERTS, FORCE_ON or FORCE_OFF.") -option(LLVM_FORCE_USE_OLD_HOST_TOOLCHAIN +option(LLVM_FORCE_USE_OLD_TOOLCHAIN "Set to ON to force using an old, unsupported host toolchain." OFF) +option(LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN + "Set to ON to only warn when using a toolchain which is about to be deprecated, instead of emitting an error." OFF) + option(LLVM_USE_INTEL_JITEVENTS "Use Intel JIT API to inform Intel(R) VTune(TM) Amplifier XE 2011 about JIT code" OFF) Modified: llvm/branches/release_80/cmake/modules/CheckCompilerVersion.cmake URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_80/cmake/modules/CheckCompilerVersion.cmake?rev=353512&r1=353511&r2=353512&view=diff ============================================================================== --- llvm/branches/release_80/cmake/modules/CheckCompilerVersion.cmake (original) +++ llvm/branches/release_80/cmake/modules/CheckCompilerVersion.cmake Fri Feb 8 03:06:27 2019 @@ -1,52 +1,94 @@ -# Check if the host compiler is new enough. LLVM requires at least GCC 4.8, -# MSVC 2015 (Update 3), or Clang 3.1. +# Check if the host compiler is new enough. +# These versions are updated based on the following policy: +# llvm.org/docs/DeveloperPolicy.html#toolchain include(CheckCXXSourceCompiles) -if(NOT DEFINED LLVM_COMPILER_CHECKED) - set(LLVM_COMPILER_CHECKED ON) +set(GCC_MIN 4.8) +set(GCC_SOFT_ERROR 5.1) +set(CLANG_MIN 3.1) +set(CLANG_SOFT_ERROR 3.5) +set(APPLECLANG_MIN 3.1) +set(APPLECLANG_SOFT_ERROR 6.0) +set(MSVC_MIN 19.00.24213.1) +set(MSVC_SOFT_ERROR 19.1) - if(NOT LLVM_FORCE_USE_OLD_TOOLCHAIN) - if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU") - if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.8) - message(FATAL_ERROR "Host GCC version must be at least 4.8!") - endif() - elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang") - if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.1) - message(FATAL_ERROR "Host Clang version must be at least 3.1!") - endif() +# Map the above GCC versions to dates: https://gcc.gnu.org/develop.html#timeline +set(GCC_MIN_DATE 20130322) +set(GCC_SOFT_ERROR_DATE 20150422) - if (CMAKE_CXX_SIMULATE_ID MATCHES "MSVC") - if (CMAKE_CXX_SIMULATE_VERSION VERSION_LESS 19.0) - message(FATAL_ERROR "Host Clang must have at least -fms-compatibility-version=19.0") - endif() - set(CLANG_CL 1) - elseif(NOT LLVM_ENABLE_LIBCXX) - # Otherwise, test that we aren't using too old of a version of libstdc++ - # with the Clang compiler. This is tricky as there is no real way to - # check the version of libstdc++ directly. Instead we test for a known - # bug in libstdc++4.6 that is fixed in libstdc++4.7. - set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) - set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES}) - set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++0x") - check_cxx_source_compiles(" -#include <atomic> -std::atomic<float> x(0.0f); -int main() { return (float)x; }" - LLVM_NO_OLD_LIBSTDCXX) - if(NOT LLVM_NO_OLD_LIBSTDCXX) - message(FATAL_ERROR "Host Clang must be able to find libstdc++4.8 or newer!") - endif() - set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) - set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES}) - endif() - elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC") - if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.0) - message(FATAL_ERROR "Host Visual Studio must be at least 2015") - elseif(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.00.24213.1) - message(WARNING "Host Visual Studio should at least be 2015 Update 3 (MSVC 19.00.24213.1)" - " due to miscompiles from earlier versions") + +if(DEFINED LLVM_COMPILER_CHECKED) + return() +endif() +set(LLVM_COMPILER_CHECKED ON) + +if(LLVM_FORCE_USE_OLD_TOOLCHAIN) + return() +endif() + +function(check_compiler_version NAME NICE_NAME MINIMUM_VERSION SOFT_ERROR_VERSION) + if(NOT CMAKE_CXX_COMPILER_ID STREQUAL NAME) + return() + endif() + if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS MINIMUM_VERSION) + message(FATAL_ERROR "Host ${NICE_NAME} version must be at least ${MINIMUM_VERSION}, your version is ${CMAKE_CXX_COMPILER_VERSION}.") + elseif(CMAKE_CXX_COMPILER_VERSION VERSION_LESS SOFT_ERROR_VERSION) + if(LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN) + message(WARNING "Host ${NICE_NAME} version should be at least ${SOFT_ERROR_VERSION} because LLVM will soon use new C++ features which your toolchain version doesn't support. Your version is ${CMAKE_CXX_COMPILER_VERSION}. Ignoring because you've set LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.") + else() + message(FATAL_ERROR "Host ${NICE_NAME} version should be at least ${SOFT_ERROR_VERSION} because LLVM will soon use new C++ features which your toolchain version doesn't support. Your version is ${CMAKE_CXX_COMPILER_VERSION}. You can temporarily opt out using LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.") + endif() + endif() +endfunction(check_compiler_version) + +check_compiler_version("GNU" "GCC" ${GCC_MIN} ${GCC_SOFT_ERROR}) +check_compiler_version("Clang" "Clang" ${CLANG_MIN} ${CLANG_SOFT_ERROR}) +check_compiler_version("AppleClang" "Apple Clang" ${APPLECLANG_MIN} ${APPLECLANG_SOFT_ERROR}) +check_compiler_version("MSVC" "Visual Studio" ${MSVC_MIN} ${MSVC_SOFT_ERROR}) + +if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang") + if (CMAKE_CXX_SIMULATE_ID MATCHES "MSVC") + if (CMAKE_CXX_SIMULATE_VERSION VERSION_LESS MSVC_MIN) + message(FATAL_ERROR "Host Clang must have at least -fms-compatibility-version=${MSVC_MIN}, your version is ${CMAKE_CXX_COMPILER_VERSION}.") + endif() + set(CLANG_CL 1) + elseif(NOT LLVM_ENABLE_LIBCXX) + # Test that we aren't using too old of a version of libstdc++. + set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) + set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES}) + set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++0x") + check_cxx_source_compiles(" +#include <iosfwd> +#if defined(__GLIBCXX__) +#if __GLIBCXX__ < ${GCC_MIN_DATE} +#error Unsupported libstdc++ version +#endif +#endif +int main() { return 0; } +" + LLVM_LIBSTDCXX_MIN) + if(NOT LLVM_LIBSTDCXX_MIN) + message(FATAL_ERROR "libstdc++ version must be at least ${GCC_MIN}.") + endif() + check_cxx_source_compiles(" +#include <iosfwd> +#if defined(__GLIBCXX__) +#if __GLIBCXX__ < ${GCC_SOFT_ERROR_DATE} +#error Unsupported libstdc++ version +#endif +#endif +int main() { return 0; } +" + LLVM_LIBSTDCXX_SOFT_ERROR) + if(NOT LLVM_LIBSTDCXX_SOFT_ERROR) + if(LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN) + message(WARNING "libstdc++ version should be at least ${GCC_SOFT_ERROR} because LLVM will soon use new C++ features which your toolchain version doesn't support. Ignoring because you've set LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.") + else() + message(FATAL_ERROR "libstdc++ version should be at least ${GCC_SOFT_ERROR} because LLVM will soon use new C++ features which your toolchain version doesn't support. You can temporarily opt out using LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.") endif() endif() + set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) + set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES}) endif() endif() Modified: llvm/branches/release_80/docs/CMake.rst URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_80/docs/CMake.rst?rev=353512&r1=353511&r2=353512&view=diff ============================================================================== --- llvm/branches/release_80/docs/CMake.rst (original) +++ llvm/branches/release_80/docs/CMake.rst Fri Feb 8 03:06:27 2019 @@ -573,6 +573,15 @@ LLVM-specific variables options, which are passed to the CCACHE_MAXSIZE and CCACHE_DIR environment variables, respectively. +**LLVM_FORCE_USE_OLD_TOOLCHAIN**:BOOL + If enabled, the compiler and standard library versions won't be checked. LLVM + may not compile at all, or might fail at runtime due to known bugs in these + toolchains. + +**LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN**:BOOL + If enabled, the compiler version check will only warn when using a toolchain + which is about to be deprecated, instead of emitting an error. + CMake Caches ============ Modified: llvm/branches/release_80/docs/DeveloperPolicy.rst URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_80/docs/DeveloperPolicy.rst?rev=353512&r1=353511&r2=353512&view=diff ============================================================================== --- llvm/branches/release_80/docs/DeveloperPolicy.rst (original) +++ llvm/branches/release_80/docs/DeveloperPolicy.rst Fri Feb 8 03:06:27 2019 @@ -22,7 +22,7 @@ This policy is also designed to accompli #. Make life as simple and easy for contributors as possible. -#. Keep the tip of tree as stable as possible. +#. Keep the top of tree as stable as possible. #. Establish awareness of the project's :ref:`copyright, license, and patent policies <copyright-license-patents>` with contributors to the project. @@ -638,6 +638,47 @@ In essences, these rules are necessary f status, but also markers to define bit-rot, and will be used to clean up the tree from unmaintained targets. +.. _toolchain: + +Updating Toolchain Requirements +------------------------------- + +We intend to require newer toolchains as time goes by. This means LLVM's +codebase can use newer versions of C++ as they get standardized. Requiring newer +toolchains to build LLVM can be painful for those building LLVM; therefore, it +will only be done through the following process: + + * Generally, try to support LLVM and GCC versions from the last 3 years at a + minimum. This time-based guideline is not strict: we may support much older + compilers, or decide to support fewer versions. + + * An RFC is sent to the `llvm-dev mailing list <http://lists.llvm.org/mailman/listinfo/llvm-dev>`_ + + - Detail upsides of the version increase (e.g. which newer C++ language or + library features LLVM should use; avoid miscompiles in particular compiler + versions, etc). + - Detail downsides on important platforms (e.g. Ubuntu LTS status). + + * Once the RFC reaches consensus, update the CMake toolchain version checks as + well as the :doc:`getting started<GettingStarted>` guide. We want to + soft-error when developers compile LLVM. We say "soft-error" because the + error can be turned into a warning using a CMake flag. This is an important + step: LLVM still doesn't have code which requires the new toolchains, but it + soon will. If you compile LLVM but don't read the mailing list, we should + tell you! + + * Ensure that at least one LLVM release has had this soft-error. Not all + developers compile LLVM top-of-tree. These release-bound developers should + also be told about upcoming changes. + + * Turn the soft-error into a hard-error after said LLVM release has branched. + + * Update the :doc:`coding standards<CodingStandards>` to allow the new + features we've explicitly approved in the RFC. + + * Start using the new features in LLVM's codebase. + + .. _copyright-license-patents: Copyright, License, and Patents Modified: llvm/branches/release_80/docs/GettingStarted.rst URL: http://llvm.org/viewvc/llvm-project/llvm/branches/release_80/docs/GettingStarted.rst?rev=353512&r1=353511&r2=353512&view=diff ============================================================================== --- llvm/branches/release_80/docs/GettingStarted.rst (original) +++ llvm/branches/release_80/docs/GettingStarted.rst Fri Feb 8 03:06:27 2019 @@ -170,7 +170,7 @@ uses the package and provides other deta Package Version Notes =========================================================== ============ ========================================== `GNU Make <http://savannah.gnu.org/projects/make>`_ 3.79, 3.79.1 Makefile/build processor -`GCC <http://gcc.gnu.org/>`_ >=4.8.0 C/C++ compiler\ :sup:`1` +`GCC <http://gcc.gnu.org/>`_ >=5.1.0 C/C++ compiler\ :sup:`1` `python <http://www.python.org/>`_ >=2.7 Automated test suite\ :sup:`2` `zlib <http://zlib.net>`_ >=1.2.3.4 Compression library\ :sup:`3` =========================================================== ============ ========================================== @@ -220,15 +220,25 @@ Host C++ Toolchain, both Compiler and St ------------------------------------------------------ LLVM is very demanding of the host C++ compiler, and as such tends to expose -bugs in the compiler. We are also planning to follow improvements and -developments in the C++ language and library reasonably closely. As such, we -require a modern host C++ toolchain, both compiler and standard library, in -order to build LLVM. - -For the most popular host toolchains we check for specific minimum versions in -our build systems: +bugs in the compiler. We also attempt to follow improvements and developments in +the C++ language and library reasonably closely. As such, we require a modern +host C++ toolchain, both compiler and standard library, in order to build LLVM. + +LLVM is written using the subset of C++ documented in :doc:`coding +standards<CodingStandards>`. To enforce this language version, we check the most +popular host toolchains for specific minimum versions in our build systems: + +* Clang 3.5 +* Apple Clang 6.0 +* GCC 5.1 +* Visual Studio 2017 + +The below versions currently soft-error as we transition to the new compiler +versions listed above. The LLVM codebase is currently known to compile correctly +with the following compilers, though this will change in the near future: * Clang 3.1 +* Apple Clang 3.1 * GCC 4.8 * Visual Studio 2015 (Update 3) @@ -282,33 +292,36 @@ The first step is to get a recent GCC to distribution on which users have struggled with the version requirements is Ubuntu Precise, 12.04 LTS. For this distribution, one easy option is to install the `toolchain testing PPA`_ and use it to install a modern GCC. There is -a really nice discussions of this on the `ask ubuntu stack exchange`_. However, -not all users can use PPAs and there are many other distributions, so it may be -necessary (or just useful, if you're here you *are* doing compiler development -after all) to build and install GCC from source. It is also quite easy to do -these days. +a really nice discussions of this on the `ask ubuntu stack exchange`_ and a +`github gist`_ with updated commands. However, not all users can use PPAs and +there are many other distributions, so it may be necessary (or just useful, if +you're here you *are* doing compiler development after all) to build and install +GCC from source. It is also quite easy to do these days. .. _toolchain testing PPA: https://launchpad.net/~ubuntu-toolchain-r/+archive/test .. _ask ubuntu stack exchange: - http://askubuntu.com/questions/271388/how-to-install-gcc-4-8-in-ubuntu-12-04-from-the-terminal + https://askubuntu.com/questions/466651/how-do-i-use-the-latest-gcc-on-ubuntu/581497#58149 +.. _github gist: + https://gist.github.com/application2000/73fd6f4bf1be6600a2cf9f56315a2d91 -Easy steps for installing GCC 4.8.2: +Easy steps for installing GCC 5.1.0: .. code-block:: console - % wget https://ftp.gnu.org/gnu/gcc/gcc-4.8.2/gcc-4.8.2.tar.bz2 - % wget https://ftp.gnu.org/gnu/gcc/gcc-4.8.2/gcc-4.8.2.tar.bz2.sig + % gcc_version=5.1.0 + % wget https://ftp.gnu.org/gnu/gcc/gcc-${gcc_version}/gcc-${gcc_version}.tar.bz2 + % wget https://ftp.gnu.org/gnu/gcc/gcc-${gcc_version}/gcc-${gcc_version}.tar.bz2.sig % wget https://ftp.gnu.org/gnu/gnu-keyring.gpg - % signature_invalid=`gpg --verify --no-default-keyring --keyring ./gnu-keyring.gpg gcc-4.8.2.tar.bz2.sig` + % signature_invalid=`gpg --verify --no-default-keyring --keyring ./gnu-keyring.gpg gcc-${gcc_version}.tar.bz2.sig` % if [ $signature_invalid ]; then echo "Invalid signature" ; exit 1 ; fi - % tar -xvjf gcc-4.8.2.tar.bz2 - % cd gcc-4.8.2 + % tar -xvjf gcc-${gcc_version}.tar.bz2 + % cd gcc-${gcc_version} % ./contrib/download_prerequisites % cd .. - % mkdir gcc-4.8.2-build - % cd gcc-4.8.2-build - % $PWD/../gcc-4.8.2/configure --prefix=$HOME/toolchains --enable-languages=c,c++ + % mkdir gcc-${gcc_version}-build + % cd gcc-${gcc_version}-build + % $PWD/../gcc-${gcc_version}/configure --prefix=$HOME/toolchains --enable-languages=c,c++ % make -j$(nproc) % make install @@ -316,7 +329,7 @@ For more details, check out the excellen of this information from. .. _GCC wiki entry: - http://gcc.gnu.org/wiki/InstallingGCC + https://gcc.gnu.org/wiki/InstallingGCC Once you have a GCC toolchain, configure your build of LLVM to use the new toolchain for your host compiler and C++ standard library. Because the new @@ -336,7 +349,7 @@ If you fail to set rpath, most LLVM bina from the loader similar to ``libstdc++.so.6: version `GLIBCXX_3.4.20' not found``. This means you need to tweak the -rpath linker flag. -When you build Clang, you will need to give *it* access to modern C++11 +When you build Clang, you will need to give *it* access to modern C++ standard library in order to use it as your new host in part of a bootstrap. There are two easy ways to do this, either build (and install) libc++ along with Clang and then use it with the ``-stdlib=libc++`` compile and link flag, _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
