1 # This CMake module is responsible for interpreting the user defined LLVM_
2 # options and executing the appropriate CMake commands to realize the users'
5 include(AddLLVMDefinitions)
6 include(CheckCCompilerFlag)
7 include(CheckCXXCompilerFlag)
9 if( CMAKE_COMPILER_IS_GNUCXX )
10 set(LLVM_COMPILER_IS_GCC_COMPATIBLE ON)
12 set(LLVM_COMPILER_IS_GCC_COMPATIBLE OFF)
13 elseif( "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" )
14 set(LLVM_COMPILER_IS_GCC_COMPATIBLE ON)
17 if(NOT LLVM_FORCE_USE_OLD_TOOLCHAIN)
18 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
19 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.7)
20 message(FATAL_ERROR "Host GCC version must be at least 4.7!")
22 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
23 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.1)
24 message(FATAL_ERROR "Host Clang version must be at least 3.1!")
27 # Also test that we aren't using too old of a version of libstdc++ with the
28 # Clang compiler. This is tricky as there is no real way to check the
29 # version of libstdc++ directly. Instead we test for a known bug in
30 # libstdc++4.6 that is fixed in libstdc++4.7.
31 if(NOT LLVM_ENABLE_LIBCXX)
32 set(CMAKE_REQUIRED_FLAGS "-std=c++0x")
34 set(CMAKE_REQUIRED_LIBRARIES "atomic")
36 check_cxx_source_compiles("
38 std::atomic<float> x(0.0f);
39 int main() { return (float)x; }"
40 LLVM_NO_OLD_LIBSTDCXX)
41 if(NOT LLVM_NO_OLD_LIBSTDCXX)
42 message(FATAL_ERROR "Host Clang must be able to find libstdc++4.7 or newer!")
45 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
46 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 17.0)
47 message(FATAL_ERROR "Host Visual Studio must be at least 2012 (MSVC 17.0)")
52 if( LLVM_ENABLE_ASSERTIONS )
53 # MSVC doesn't like _DEBUG on release builds. See PR 4379.
55 add_definitions( -D_DEBUG )
57 # On non-Debug builds cmake automatically defines NDEBUG, so we
58 # explicitly undefine it:
59 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )
60 add_definitions( -UNDEBUG )
61 # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines.
62 set(REGEXP_NDEBUG "(^| )[/-]D *NDEBUG($| )")
63 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
64 CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE}")
65 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
66 CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
67 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
68 CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS_MINSIZEREL}")
71 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELEASE" )
72 if( NOT MSVC_IDE AND NOT XCODE )
73 add_definitions( -DNDEBUG )
79 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
87 # Maximum path length is 160 for non-unicode paths
94 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
96 set(LLVM_HAVE_LINK_VERSION_SCRIPT 1)
98 # FIXME: Maximum path length is currently set to 'safe' fixed value
101 MESSAGE(SEND_ERROR "Unable to determine platform")
105 set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX})
106 set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
107 set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_MODULE_SUFFIX})
109 function(add_flag_or_print_warning flag)
110 check_c_compiler_flag(${flag} C_SUPPORTS_FLAG)
111 check_cxx_compiler_flag(${flag} CXX_SUPPORTS_FLAG)
112 if (C_SUPPORTS_FLAG AND CXX_SUPPORTS_FLAG)
113 message(STATUS "Building with ${flag}")
114 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE)
115 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE)
117 message(WARNING "${flag} is not supported.")
121 function(append value)
122 foreach(variable ${ARGN})
123 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
127 function(append_if condition value)
129 foreach(variable ${ARGN})
130 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
135 macro(add_flag_if_supported flag)
136 check_c_compiler_flag(${flag} C_SUPPORTS_FLAG)
137 append_if(C_SUPPORTS_FLAG "${flag}" CMAKE_C_FLAGS)
138 check_cxx_compiler_flag(${flag} CXX_SUPPORTS_FLAG)
139 append_if(CXX_SUPPORTS_FLAG "${flag}" CMAKE_CXX_FLAGS)
142 if( LLVM_ENABLE_PIC )
144 # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
145 # know how to disable this, so just force ENABLE_PIC off for now.
146 message(WARNING "-fPIC not supported with Xcode.")
147 elseif( WIN32 OR CYGWIN)
148 # On Windows all code is PIC. MinGW warns if -fPIC is used.
150 add_flag_or_print_warning("-fPIC")
153 # MinGW warns if -fvisibility-inlines-hidden is used.
155 check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG)
156 append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS)
161 if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
162 # TODO: support other platforms and toolchains.
163 if( LLVM_BUILD_32_BITS )
164 message(STATUS "Building 32 bits executables and libraries.")
165 add_llvm_definitions( -m32 )
166 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32")
167 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32")
168 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32")
169 endif( LLVM_BUILD_32_BITS )
170 endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
172 # On Win32 using MS tools, provide an option to set the number of parallel jobs
175 set(LLVM_COMPILER_JOBS "0" CACHE STRING
176 "Number of parallel compiler jobs. 0 means use all processors. Default is 0.")
177 if( NOT LLVM_COMPILER_JOBS STREQUAL "1" )
178 if( LLVM_COMPILER_JOBS STREQUAL "0" )
179 add_llvm_definitions( /MP )
183 "Due to a bug in CMake only 0 and 1 is supported for "
184 "LLVM_COMPILER_JOBS when generating for Visual Studio 2010")
186 message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS})
187 add_llvm_definitions( /MP${LLVM_COMPILER_JOBS} )
191 message(STATUS "Parallel compilation disabled")
196 include(ChooseMSVCCRT)
198 if( NOT (${CMAKE_VERSION} VERSION_LESS 2.8.11) )
199 # set stack reserved size to ~10MB
200 # CMake previously automatically set this value for MSVC builds, but the
201 # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default
202 # value (1 MB) which is not enough for us in tasks such as parsing recursive
203 # C++ templates in Clang.
204 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /STACK:10000000")
208 # MSVC 10 will complain about headers in the STL not being exported, but
209 # will not complain in MSVC 11.
210 add_llvm_definitions(
211 -wd4275 # Suppress 'An exported class was derived from a class that was not exported.'
214 add_llvm_definitions(-D_VARIADIC_MAX=10)
217 # Add definitions that make MSVC much less annoying.
218 add_llvm_definitions(
219 # For some reason MS wants to deprecate a bunch of standard functions...
220 -D_CRT_SECURE_NO_DEPRECATE
221 -D_CRT_SECURE_NO_WARNINGS
222 -D_CRT_NONSTDC_NO_DEPRECATE
223 -D_CRT_NONSTDC_NO_WARNINGS
224 -D_SCL_SECURE_NO_DEPRECATE
225 -D_SCL_SECURE_NO_WARNINGS
228 -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned'
229 -wd4180 # Suppress 'qualifier applied to function type has no meaning; ignored'
230 -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data'
231 -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data'
232 -wd4345 # Suppress 'behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized'
233 -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized'
234 -wd4355 # Suppress ''this' : used in base member initializer list'
235 -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated'
236 -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible'
237 -wd4800 # Suppress ''type' : forcing value to bool 'true' or 'false' (performance warning)'
238 -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception'
241 -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning.
243 # Promoted warnings to errors.
244 -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error.
248 if (LLVM_ENABLE_WARNINGS)
249 add_llvm_definitions( /W4 )
250 if (LLVM_ENABLE_PEDANTIC)
251 # No MSVC equivalent available
252 endif (LLVM_ENABLE_PEDANTIC)
253 endif (LLVM_ENABLE_WARNINGS)
254 if (LLVM_ENABLE_WERROR)
255 add_llvm_definitions( /WX )
256 endif (LLVM_ENABLE_WERROR)
257 elseif( LLVM_COMPILER_IS_GCC_COMPATIBLE )
258 if (LLVM_ENABLE_WARNINGS)
259 append("-Wall -W -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
261 # Turn off missing field initializer warnings for gcc to avoid noise from
262 # false positives with empty {}. Turn them on otherwise (they're off by
263 # default for clang).
264 check_cxx_compiler_flag("-Wmissing-field-initializers" CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
265 if (CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
266 if (CMAKE_COMPILER_IS_GNUCXX)
267 append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
269 append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
273 append_if(LLVM_ENABLE_PEDANTIC "-pedantic -Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
274 check_cxx_compiler_flag("-Werror -Wcovered-switch-default" CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG)
275 append_if(CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG "-Wcovered-switch-default" CMAKE_CXX_FLAGS)
276 check_c_compiler_flag("-Werror -Wcovered-switch-default" C_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG)
277 append_if(C_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG "-Wcovered-switch-default" CMAKE_C_FLAGS)
278 append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS)
279 append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS)
280 check_cxx_compiler_flag("-Werror -Wnon-virtual-dtor" CXX_SUPPORTS_NON_VIRTUAL_DTOR_FLAG)
281 append_if(CXX_SUPPORTS_NON_VIRTUAL_DTOR_FLAG "-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
282 endif (LLVM_ENABLE_WARNINGS)
283 if (LLVM_ENABLE_WERROR)
284 add_llvm_definitions( -Werror )
285 endif (LLVM_ENABLE_WERROR)
286 if (LLVM_ENABLE_CXX11)
287 check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11)
288 append_if(CXX_SUPPORTS_CXX11 "-std=c++11" CMAKE_CXX_FLAGS)
289 endif (LLVM_ENABLE_CXX11)
290 if(LLVM_ENABLE_LIBCXX)
291 check_cxx_compiler_flag("-stdlib=libc++" CXX_SUPPORTS_STDLIB)
292 append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_CXX_FLAGS)
293 append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_EXE_LINKER_FLAGS)
294 append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_SHARED_LINKER_FLAGS)
295 append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_MODULE_LINKER_FLAGS)
299 macro(append_common_sanitizer_flags)
300 # Append -fno-omit-frame-pointer and turn on debug info to get better
302 add_flag_if_supported("-fno-omit-frame-pointer")
303 if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND
304 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")
305 add_flag_if_supported("-gline-tables-only")
307 # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large.
308 if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
309 add_flag_if_supported("-O1")
313 # Turn on sanitizers if necessary.
314 if(LLVM_USE_SANITIZER)
316 if (LLVM_USE_SANITIZER STREQUAL "Address")
317 append_common_sanitizer_flags()
318 add_flag_or_print_warning("-fsanitize=address")
319 elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?")
320 append_common_sanitizer_flags()
321 add_flag_or_print_warning("-fsanitize=memory")
322 if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins")
323 add_flag_or_print_warning("-fsanitize-memory-track-origins")
326 message(WARNING "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}")
329 message(WARNING "LLVM_USE_SANITIZER is not supported on this platform.")
333 # Turn on -gsplit-dwarf if requested
334 if(LLVM_USE_SPLIT_DWARF)
335 add_llvm_definitions("-gsplit-dwarf")
338 add_llvm_definitions( -D__STDC_CONSTANT_MACROS )
339 add_llvm_definitions( -D__STDC_FORMAT_MACROS )
340 add_llvm_definitions( -D__STDC_LIMIT_MACROS )
342 # clang doesn't print colored diagnostics when invoked from Ninja
344 CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND
345 CMAKE_GENERATOR STREQUAL "Ninja")
346 append("-fcolor-diagnostics" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)