#
# This file sets up
#
-# DEAL_II_WITH_CXX14
-# DEAL_II_WITH_CXX17
+# DEAL_II_HAVE_CXX17
#
# DEAL_II_HAVE_ATTRIBUTE_FALLTHROUGH
# DEAL_II_HAVE_CXX11_IS_TRIVIALLY_COPYABLE
#
+########################################################################
+# #
+# C++ Version Support: #
+# #
+########################################################################
+
#
# MSVC needs different compiler flags to turn warnings into errors
# additionally a suitable exception handling model is required
SET(_werror_flag "-Werror")
ENDIF()
+ADD_FLAGS(CMAKE_REQUIRED_FLAGS "${DEAL_II_CXX_FLAGS} ${_werror_flag}")
-########################################################################
-# #
-# C++ Version Support: #
-# #
-########################################################################
-
-
-#
-# BIG DISCLAIMER
#
-# Frankly speaking - this whole file is a mess and has to be rewritten and
-# restructured at some point. So, if you are the lucky one who wants to add
-# DEAL_II_WITH_CXX2X support, do not add yet another 300 lines of spaghetti
-# code but restructure the whole thing to something sane.
-#
-
-
+# Rerun all checks if compile flags change:
#
-IF(DEAL_II_WITH_CXX17 AND DEFINED DEAL_II_WITH_CXX14 AND NOT DEAL_II_WITH_CXX14)
- MESSAGE(FATAL_ERROR
- "Compiling deal.II with C++17 support (i.e., DEAL_II_WITH_CXX17=ON) requires"
- " that C++14 support not be explicitly disabled (i.e., DEAL_II_WITH_CXX14 may"
- " not be set to a logically false value)."
- )
-ENDIF()
-
-IF(DEFINED DEAL_II_WITH_CXX14 AND NOT DEAL_II_WITH_CXX14)
- SET(DEAL_II_WITH_CXX17 OFF CACHE STRING "" FORCE)
-ENDIF()
+UNSET_IF_CHANGED(CHECK_CXX_FEATURES_FLAGS_SAVED
+ "${CMAKE_REQUIRED_FLAGS}"
+ DEAL_II_HAVE_CXX17_FEATURES
+ DEAL_II_HAVE_CXX17_CONSTEXPR_LAMBDA_BUG_OK
+ DEAL_II_HAVE_CXX14_FEATURES
+ DEAL_II_HAVE_CXX14_CLANGAUTODEBUG_BUG_OK
+ DEAL_II_HAVE_CXX11_FEATURES
+ DEAL_II_HAVE_CXX11_FUNCTIONAL_LLVMBUG20084_OK
+ )
#
-# Check the user supplied DEAL_II_CXX_VERSION_FLAG
+# Test that the c++17 attributes are supported.
#
+CHECK_CXX_SOURCE_COMPILES(
+ "
+ #include <iostream>
-IF(NOT "${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "")
- CHECK_CXX_COMPILER_FLAG(${DEAL_II_CXX_VERSION_FLAG} DEAL_II_CXX_VERSION_FLAG_VALID)
- IF(NOT DEAL_II_CXX_VERSION_FLAG_VALID)
- MESSAGE(FATAL_ERROR
- "The supplied flag \"${DEAL_II_CXX_VERSION_FLAG}\" was not recognized "
- "by the compiler."
- )
- ENDIF()
-
- #
- # A quick check that may, hopefully, give a more useful error message
- #
- IF("${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "-std=c++98" OR
- "${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "-std=c++03")
- MESSAGE(FATAL_ERROR
- "\ndeal.II no longer supports compilation under the C++98 or C++03 "
- "standards: please either specify a value for DEAL_II_CXX_VERSION_FLAG "
- "corresponding to C++11 or leave the field blank (so that CMake may "
- "automatically determine a valid version flag).\n"
- )
- ENDIF()
-
- SET(_user_provided_cxx_version_flag TRUE)
-ELSE()
- SET(_user_provided_cxx_version_flag FALSE)
-ENDIF()
+ #if __cplusplus < 201703L && !defined(_MSC_VER) && !defined(__INTEL_COMPILER)
+ # error \"insufficient support for C++17\"
+ #endif
-#
-# A macro to check for various C++ version flags
-#
-
-MACRO(_check_cxx_flag _suffix)
- IF("${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "")
- IF(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
- CHECK_CXX_COMPILER_FLAG("/std:c++${_suffix}" DEAL_II_HAVE_FLAG_stdcxx${_suffix})
- IF(DEAL_II_HAVE_FLAG_stdcxx${_suffix})
- SET(DEAL_II_CXX_VERSION_FLAG "/std:c++${_suffix}")
- ENDIF()
- ELSE()
- CHECK_CXX_COMPILER_FLAG("-std=c++${_suffix}" DEAL_II_HAVE_FLAG_stdcxx${_suffix})
- IF(DEAL_II_HAVE_FLAG_stdcxx${_suffix})
- SET(DEAL_II_CXX_VERSION_FLAG "-std=c++${_suffix}")
- ENDIF()
- ENDIF()
- ENDIF()
-ENDMACRO()
-
-MACRO(_check_version _version _symbolic)
- _check_cxx_flag("${_version}")
- _check_cxx_flag("${_symbolic}")
- IF(DEAL_II_WITH_CXX${_version} AND "${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "")
- MESSAGE(FATAL_ERROR
- "C++${_version} support was requested but CMake was not able to find a valid C++${_version}"
- " flag. Try to manually specify DEAL_II_CXX_VERSION_FLAG and rerun CMake."
- )
- ENDIF()
-ENDMACRO()
-
-#
-# Check for proper C++17 support and set up DEAL_II_HAVE_CXX17:
-#
-IF(NOT DEFINED DEAL_II_WITH_CXX17 OR DEAL_II_WITH_CXX17)
- _check_version("17" "1z")
-
- IF(NOT "${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "")
- # Set CMAKE_REQUIRED_FLAGS for the unit tests
- MESSAGE(STATUS "Using C++ version flag \"${DEAL_II_CXX_VERSION_FLAG}\"")
- ADD_FLAGS(CMAKE_REQUIRED_FLAGS "${DEAL_II_CXX_VERSION_FLAG} ${_werror_flag}")
-
- UNSET_IF_CHANGED(CHECK_CXX_FEATURES_FLAGS_CXX17_SAVED
- "${CMAKE_REQUIRED_FLAGS}${DEAL_II_CXX_VERSION_FLAG}"
- DEAL_II_HAVE_CXX17_ATTRIBUTES
- DEAL_II_HAVE_CXX17_IF_CONSTEXPR
- )
-
- #
- # Test that the c++17 attributes are supported.
- #
- CHECK_CXX_SOURCE_COMPILES(
- "
- #include <iostream>
-
- [[nodiscard]] int test_nodiscard()
- {
- return 1;
- }
+ [[nodiscard]] int test_nodiscard()
+ {
+ return 1;
+ }
- int main()
- {
- const unsigned int n=1;
- switch (n)
- {
- case 1:
- std::cout << n;
- [[fallthrough]];
- case 2:
- std::cout << n;
- }
-
- [[maybe_unused]] int i = test_nodiscard();
- }
- "
- DEAL_II_HAVE_CXX17_ATTRIBUTES)
-
- #
- # Test that the c++17 if constexpr is supported.
- #
- CHECK_CXX_SOURCE_COMPILES(
- "
- int main()
- {
- constexpr bool flag = false;
- if constexpr(flag)
- return 1;
- return 0;
- }
- "
- DEAL_II_HAVE_CXX17_IF_CONSTEXPR)
-
- #
- # Some compilers treat lambdas as constexpr functions when compiling
- # with C++17 support even if they don't fulfill all the constexpr
- # function requirements. Consequently, these compilers don't allow
- # try-blocks or non-literal return types in lambdas. This is a bug.
- #
- CHECK_CXX_SOURCE_COMPILES(
- "
- #include <string>
-
- int main()
- {
- auto c = []()
- {
- return std::string{};
- }();
- (void) c;
-
- return []()
- {
- try
- {}
- catch(...)
- {}
- return 0;
- }();
- }
- "
- DEAL_II_NON_CONSTEXPR_LAMBDA)
-
- RESET_CMAKE_REQUIRED()
- ENDIF()
-
- IF( DEAL_II_HAVE_CXX17_ATTRIBUTES AND
- DEAL_II_HAVE_CXX17_IF_CONSTEXPR AND
- DEAL_II_NON_CONSTEXPR_LAMBDA)
- SET(DEAL_II_HAVE_CXX17 TRUE)
- ELSE()
- IF(NOT _user_provided_cxx_version_flag)
- SET(DEAL_II_CXX_VERSION_FLAG "")
- ENDIF()
- ENDIF()
-ENDIF()
+ int main()
+ {
+ const unsigned int n=1;
+ switch (n)
+ {
+ case 1:
+ std::cout << n;
+ [[fallthrough]];
+ case 2:
+ std::cout << n;
+ }
+ [[maybe_unused]] int i = test_nodiscard();
+ constexpr bool flag = false;
+ if constexpr(flag)
+ return 1;
+ return 0;
+ }
+ "
+ DEAL_II_HAVE_CXX17_FEATURES)
#
-# Check for proper C++14 support and set up DEAL_II_HAVE_CXX14:
+# Some compilers treat lambdas as constexpr functions when compiling with
+# C++17 support even if they don't fulfill all the constexpr function
+# requirements. Consequently, these compilers don't allow try-blocks or
+# non-literal return types in lambdas. This is a bug.
#
-IF(NOT DEFINED DEAL_II_WITH_CXX14 OR DEAL_II_WITH_CXX14)
- _check_version("14" "1y")
+CHECK_CXX_SOURCE_COMPILES(
+ "
+ #include <string>
- IF(NOT "${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "")
+ int main()
+ {
+ auto c = []()
+ {
+ return std::string{};
+ }();
+ (void) c;
- UNSET_IF_CHANGED(CHECK_CXX_FEATURES_FLAGS_CXX14_SAVED
- "${CMAKE_REQUIRED_FLAGS}${DEAL_II_CXX_VERSION_FLAG}"
- DEAL_II_HAVE_CXX14_CLANGAUTODEBUG_BUG_OK
- DEAL_II_HAVE_CXX14_CONSTEXPR_STDMAXMIN
- DEAL_II_HAVE_CXX14_MAKE_UNIQUE
- )
+ return []()
+ {
+ try
+ {}
+ catch(...)
+ {}
+ return 0;
+ }();
+ }
+ "
+ DEAL_II_HAVE_CXX17_CONSTEXPR_LAMBDA_BUG_OK)
- # Set CMAKE_REQUIRED_FLAGS for the unit tests
- ADD_FLAGS(CMAKE_REQUIRED_FLAGS "${DEAL_II_CXX_VERSION_FLAG}")
+#
+# Check some generic C++14 features
+#
+CHECK_CXX_SOURCE_COMPILES(
+ "
+ #include <memory>
+ #include <algorithm>
- #
- # We assume std::make_unique works
- #
- CHECK_CXX_SOURCE_COMPILES(
- "
- #include <memory>
+ // Check the version language macro, but skip MSVC because
+ // MSVC reports 199711 even in MSVC 2017.
+ #if __cplusplus < 201402L && !defined(_MSC_VER) && !defined(__INTEL_COMPILER)
+ # error \"insufficient support for C++14\"
+ #endif
- int main()
- {
- auto ptr = std::make_unique<int>(42);
- return 0;
- }
- "
- DEAL_II_HAVE_CXX14_MAKE_UNIQUE)
-
- #
- # This test checks constexpr std::max/min support. Unfortunately,
- # gcc-4.9 claims to support C++14 but fails to provide a constexpr
- # compatible std::max/min. Disable C++14 support in this case.
- #
- CHECK_CXX_SOURCE_COMPILES(
- "
- #include <algorithm>
- int main()
- {
- constexpr int max = std::max(0,1);
- (void) max;
- }
- "
- DEAL_II_HAVE_CXX14_CONSTEXPR_STDMAXMIN)
-
-
- #
- # Clang-3.5* or older, bail out with a spurious error message in case
- # of an undeduced auto return type.
- #
- # https://llvm.org/bugs/show_bug.cgi?id=16876
- #
- SET(_flags "${DEAL_II_CXX_FLAGS_DEBUG}")
- STRIP_FLAG(_flags "-Wa,--compress-debug-sections")
- ADD_FLAGS(CMAKE_REQUIRED_FLAGS "${_flags}")
- CHECK_CXX_SOURCE_COMPILES(
- "
- struct foo
- {
- auto func();
- };
- int main()
- {
- foo bar;
- (void) bar;
- }
- "
- DEAL_II_HAVE_CXX14_CLANGAUTODEBUG_BUG_OK)
-
- RESET_CMAKE_REQUIRED()
- ENDIF()
-
- IF( DEAL_II_HAVE_CXX14_MAKE_UNIQUE AND
- DEAL_II_HAVE_CXX14_CLANGAUTODEBUG_BUG_OK AND
- DEAL_II_HAVE_CXX14_CONSTEXPR_STDMAXMIN)
- SET(DEAL_II_HAVE_CXX14 TRUE)
- ELSE()
- IF(NOT _user_provided_cxx_version_flag)
- SET(DEAL_II_CXX_VERSION_FLAG "")
- ENDIF()
- ENDIF()
-ENDIF()
+ int main()
+ {
+ auto ptr = std::make_unique<int>(42);
+ constexpr int max = std::max(0, 1);
+ (void) ptr;
+ (void) max;
+ return 0;
+ }
+ "
+ DEAL_II_HAVE_CXX14_FEATURES)
#
-# Check for proper C++11 support.
+# Clang-3.5* or older, bail out with a spurious error message in case
+# of an undeduced auto return type.
#
+# https://llvm.org/bugs/show_bug.cgi?id=16876
+#
+SET(_flags "${DEAL_II_CXX_FLAGS_DEBUG}")
+STRIP_FLAG(_flags "-Wa,--compress-debug-sections")
+ADD_FLAGS(CMAKE_REQUIRED_FLAGS "${_flags}")
+CHECK_CXX_SOURCE_COMPILES(
+ "
+ struct foo
+ {
+ auto func();
+ };
+ int main()
+ {
+ foo bar;
+ (void) bar;
+ }
+ "
+ DEAL_II_HAVE_CXX14_CLANGAUTODEBUG_BUG_OK)
#
-# Set up a default C++11 flag in case both C++14 detection failed and the user
-# did not specify a flag:
+# Check some generic C++11 features
#
-IF("${DEAL_II_CXX_VERSION_FLAG}" STREQUAL "")
- _check_version("11" "0x")
-ENDIF()
-
-UNSET_IF_CHANGED(CHECK_CXX_FEATURES_FLAGS_CXX11_SAVED
- "${CMAKE_REQUIRED_FLAGS}${DEAL_II_CXX_VERSION_FLAG}"
- DEAL_II_HAVE_CXX11_FEATURES
- DEAL_II_HAVE_CXX11_FUNCTIONAL_LLVMBUG20084_OK
- DEAL_II_HAVE_CXX11_ICCLIBSTDCPP47CXX11BUG_OK
- DEAL_II_HAVE_CXX11_ICCNUMERICLIMITSBUG_OK
- DEAL_II_HAVE_CXX11_MACOSXC99BUG_OK
- )
-
ADD_FLAGS(CMAKE_REQUIRED_FLAGS "${DEAL_II_CXX_VERSION_FLAG}")
CHECK_CXX_SOURCE_COMPILES(
"
"
DEAL_II_HAVE_CXX11_FEATURES)
+#
# clang libc++ bug, see https://llvm.org/bugs/show_bug.cgi?id=20084
+#
CHECK_CXX_SOURCE_COMPILES(
"
#include <functional>
"
DEAL_II_HAVE_CXX11_FUNCTIONAL_LLVMBUG20084_OK)
-#
-# On Mac OS-X 10.9 with recent gcc compilers in C++11 mode linking to
-# some standard C library functions, notably toupper and tolower, fail
-# due to unresolved references to these functions.
-#
-# Thanks to Denis Davydov for the testcase.
-#
-# Matthias Maier, 2013
-#
-CHECK_CXX_SOURCE_COMPILES(
- "
- #include <ctype.h>
- int main ()
- {
- int c = toupper('a');
- (void) c;
- }
- "
- DEAL_II_HAVE_CXX11_MACOSXC99BUG_OK)
-
-
-#
-# icc-13 triggers an internal compiler error when compiling
-# std::numeric_limits<...>::min() with -std=c++0x [1].
-#
-# Reported by Ted Kord.
-#
-# - Matthias Maier, 2013
-#
-# [1] http://software.intel.com/en-us/forums/topic/328902
-#
-CHECK_CXX_SOURCE_COMPILES(
- "
- #include <limits>
- struct Integer
- {
- static const int min_int_value;
- static const int max_int_value;
- };
- const int Integer::min_int_value = std::numeric_limits<int>::min();
- const int Integer::max_int_value = std::numeric_limits<int>::max();
- int main() { return 0; }
- "
- DEAL_II_HAVE_CXX11_ICCNUMERICLIMITSBUG_OK)
-
-
-#
-# icc-14.0.0 has an astonishing bug [1] where it hits an internal compiler
-# error when run in C++11 mode with libstdc++-4.7 (from gcc).
-#
-# [1] http://software.intel.com/en-us/forums/topic/472385
-#
-# - Matthias Maier, 2013
-#
-CHECK_CXX_SOURCE_COMPILES(
- "
- #include <vector>
- template<typename T> void foo()
- {
- std::vector<double> data(100);
- }
- int main()
- {
- foo<int>();
- }
- "
- DEAL_II_HAVE_CXX11_ICCLIBSTDCPP47CXX11BUG_OK)
RESET_CMAKE_REQUIRED()
-IF( DEAL_II_HAVE_CXX11_FEATURES AND
- DEAL_II_HAVE_CXX11_FUNCTIONAL_LLVMBUG20084_OK AND
- DEAL_II_HAVE_CXX11_MACOSXC99BUG_OK AND
- DEAL_II_HAVE_CXX11_ICCNUMERICLIMITSBUG_OK AND
- DEAL_II_HAVE_CXX11_ICCLIBSTDCPP47CXX11BUG_OK )
- # we require C++11 so this is fine
+IF(DEAL_II_HAVE_CXX17_FEATURES AND
+ DEAL_II_HAVE_CXX17_CONSTEXPR_LAMBDA_BUG_OK)
+ MESSAGE(STATUS "C++17 support is enabled.")
+ SET(DEAL_II_HAVE_CXX17 TRUE)
ELSE()
- MESSAGE(FATAL_ERROR "\n"
- "The current combination of compiler and C++ version flag is missing some "
- "features of the C++11 version of the language necessary for compiling "
- "deal.II. Please ensure that the CMake variable DEAL_II_CXX_VERSION_FLAG is "
- "set to the correct flag to enable C++11 support; if it is already set and "
- "you still see this message then you will need to upgrade your compiler.\n")
-ENDIF()
-
-
-#
-# Set up a configuration option for C++14 and C++17 support:
-#
-
-IF (DEAL_II_HAVE_CXX17 AND NOT DEAL_II_HAVE_CXX14)
- MESSAGE(STATUS "Disabling CXX17 support because CXX14 detection failed.")
+ MESSAGE(STATUS "C++17 support is disabled.")
SET(DEAL_II_HAVE_CXX17 FALSE)
ENDIF()
-OPTION(DEAL_II_WITH_CXX14
- "Compile deal.II using C++14 language standard."
- ${DEAL_II_HAVE_CXX14}
- )
-LIST(APPEND DEAL_II_FEATURES CXX14)
-SET(FEATURE_CXX14_PROCESSED TRUE)
-
-OPTION(DEAL_II_WITH_CXX17
- "Compile deal.II using C++17 language standard."
- ${DEAL_II_HAVE_CXX17}
- )
-LIST(APPEND DEAL_II_FEATURES CXX17)
-SET(FEATURE_CXX17_PROCESSED TRUE)
-
-#
-# Bail out if user requested support for a certain C++ version (e.g.,
-# DEAL_II_WITH_CXX14) but support is not available due to above tests
-#
-
-MACRO(_bailout _version _symbolic)
- IF(DEAL_II_WITH_CXX${_version} AND NOT DEAL_II_HAVE_CXX${_version})
- MESSAGE(FATAL_ERROR "\n"
- "C++${_version} support was requested (DEAL_II_WITH_CXX${_version}=${DEAL_II_WITH_CXX${_version}}) "
- "but it is not supported by the current compiler.\n"
- "Please disable C++${_version} support, i.e. configure with\n"
- " -DDEAL_II_WITH_CXX${_version}=FALSE,\n"
- "or use a different compiler, instead. (If the compiler flag for C++${_version} "
- "support differs from \"-std=c++${_symbolic}\" or \"-std=c++${_version}\", "
- "a suitable compiler flag has to be specified manually via\n"
- " -DDEAL_II_CXX_VERSION_FLAG=\"...\"\n\n"
- )
- ENDIF()
-ENDMACRO()
-
-_bailout("14" "1y")
-_bailout("17" "1z")
-
-#
-# Some compilers (notably GCC6 and up) default to C++14 (more exactly, GNU++14,
-# which contains some extensions) but most compilers default to C++98. Hence,
-# try to avoid adding an extra flag by doing one last test:
-#
-RESET_CMAKE_REQUIRED()
-IF(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
- ADD_FLAGS(CMAKE_REQUIRED_FLAGS "/Zc:__cplusplus")
-ENDIF()
-CHECK_CXX_SOURCE_COMPILES(
- "
- #include <memory>
-
- #if __cplusplus < 201103L
- # error \"The compiler does not default to C++11 or newer.\"
- #endif
-
- auto main() -> int
- {
- auto p0 = std::unique_ptr<int>();
- auto p1 = std::move(p0);
- }
- "
- DEAL_II_COMPILER_DEFAULTS_TO_CXX11_OR_NEWER)
-RESET_CMAKE_REQUIRED()
-
-IF(_user_provided_cxx_version_flag OR
- NOT DEAL_II_COMPILER_DEFAULTS_TO_CXX11_OR_NEWER OR
- (DEAL_II_COMPILER_DEFAULTS_TO_CXX11_OR_NEWER AND NOT DEAL_II_WITH_CXX14))
- ADD_FLAGS(DEAL_II_CXX_FLAGS "${DEAL_II_CXX_VERSION_FLAG}")
- MESSAGE(STATUS "Using C++ version flag \"${DEAL_II_CXX_VERSION_FLAG}\"")
-ENDIF ()
-
-IF (DEAL_II_WITH_CXX17)
- ADD_FLAGS(DEAL_II_CXX_FLAGS "${DEAL_II_CXX_VERSION_FLAG}")
- MESSAGE(STATUS "DEAL_II_WITH_CXX14 successfully set up")
- MESSAGE(STATUS "DEAL_II_WITH_CXX17 successfully set up")
-ELSEIF (DEAL_II_WITH_CXX14)
- ADD_FLAGS(DEAL_II_CXX_FLAGS "${DEAL_II_CXX_VERSION_FLAG}")
- MESSAGE(STATUS "DEAL_II_WITH_CXX14 successfully set up")
+IF(DEAL_II_HAVE_CXX14_FEATURES AND
+ DEAL_II_HAVE_CXX14_CLANGAUTODEBUG_BUG_OK AND
+ DEAL_II_HAVE_CXX11_FEATURES AND
+ DEAL_II_HAVE_CXX11_FUNCTIONAL_LLVMBUG20084_OK)
+ # we require C++14 so this is fine
ELSE()
- MESSAGE(STATUS
- "DEAL_II_WITH_CXX17 and DEAL_II_WITH_CXX14 are both disabled")
+ MESSAGE(FATAL_ERROR
+ "\nThe current version of deal.II requires a compiler with enabled "
+ "C++14 support. Make sure to use a modern enough compiler (GCC version "
+ "5 onwards, Clang version 4 onwards, or Microsoft MS VS 2015 onwards) "
+ "and check that the compiler flag \"-std=\" is either unset, or set to "
+ "at least c++14.\n\n"
+ )
ENDIF()
IF(NOT CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
ADD_FLAGS(CMAKE_REQUIRED_FLAGS "-Wno-unused-command-line-argument")
ENDIF()
+
#
# first try the attribute [[fallthrough]]
#
projects / dealii.git / commitdiff