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(NOT LLVM_FORCE_USE_OLD_TOOLCHAIN)
10 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
11 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.7)
12 message(FATAL_ERROR "Host GCC version must be at least 4.7!")
14 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
15 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.1)
16 message(FATAL_ERROR "Host Clang version must be at least 3.1!")
19 # Also test that we aren't using too old of a version of libstdc++ with the
20 # Clang compiler. This is tricky as there is no real way to check the
21 # version of libstdc++ directly. Instead we test for a known bug in
22 # libstdc++4.6 that is fixed in libstdc++4.7.
23 if(NOT LLVM_ENABLE_LIBCXX)
24 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
25 set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
26 set(CMAKE_REQUIRED_FLAGS "-std=c++0x")
28 set(CMAKE_REQUIRED_LIBRARIES "atomic")
30 check_cxx_source_compiles("
32 std::atomic<float> x(0.0f);
33 int main() { return (float)x; }"
34 LLVM_NO_OLD_LIBSTDCXX)
35 if(NOT LLVM_NO_OLD_LIBSTDCXX)
36 message(FATAL_ERROR "Host Clang must be able to find libstdc++4.7 or newer!")
38 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
39 set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES})
41 elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
42 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 17.0)
43 message(FATAL_ERROR "Host Visual Studio must be at least 2012 (MSVC 17.0)")
48 if( LLVM_ENABLE_ASSERTIONS )
49 # MSVC doesn't like _DEBUG on release builds. See PR 4379.
51 add_definitions( -D_DEBUG )
53 # On non-Debug builds cmake automatically defines NDEBUG, so we
54 # explicitly undefine it:
55 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )
56 add_definitions( -UNDEBUG )
57 # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines.
58 set(REGEXP_NDEBUG "(^| )[/-]D *NDEBUG($| )")
59 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
60 CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE}")
61 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
62 CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
63 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
64 CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS_MINSIZEREL}")
67 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELEASE" )
68 if( NOT MSVC_IDE AND NOT XCODE )
69 add_definitions( -DNDEBUG )
75 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
83 # Maximum path length is 160 for non-unicode paths
90 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
92 set(LLVM_HAVE_LINK_VERSION_SCRIPT 1)
94 # FIXME: Maximum path length is currently set to 'safe' fixed value
97 MESSAGE(SEND_ERROR "Unable to determine platform")
101 set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX})
102 set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
103 set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_MODULE_SUFFIX})
105 function(add_flag_or_print_warning flag)
106 check_c_compiler_flag(${flag} C_SUPPORTS_FLAG)
107 check_cxx_compiler_flag(${flag} CXX_SUPPORTS_FLAG)
108 if (C_SUPPORTS_FLAG AND CXX_SUPPORTS_FLAG)
109 message(STATUS "Building with ${flag}")
110 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE)
111 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE)
113 message(WARNING "${flag} is not supported.")
117 function(append value)
118 foreach(variable ${ARGN})
119 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
123 function(append_if condition value)
125 foreach(variable ${ARGN})
126 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
131 macro(add_flag_if_supported flag)
132 check_c_compiler_flag(${flag} C_SUPPORTS_FLAG)
133 append_if(C_SUPPORTS_FLAG "${flag}" CMAKE_C_FLAGS)
134 check_cxx_compiler_flag(${flag} CXX_SUPPORTS_FLAG)
135 append_if(CXX_SUPPORTS_FLAG "${flag}" CMAKE_CXX_FLAGS)
138 if( LLVM_ENABLE_PIC )
140 # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
141 # know how to disable this, so just force ENABLE_PIC off for now.
142 message(WARNING "-fPIC not supported with Xcode.")
143 elseif( WIN32 OR CYGWIN)
144 # On Windows all code is PIC. MinGW warns if -fPIC is used.
146 add_flag_or_print_warning("-fPIC")
149 # MinGW warns if -fvisibility-inlines-hidden is used.
151 check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG)
152 append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS)
157 if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
158 # TODO: support other platforms and toolchains.
159 if( LLVM_BUILD_32_BITS )
160 message(STATUS "Building 32 bits executables and libraries.")
161 add_llvm_definitions( -m32 )
162 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32")
163 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32")
164 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32")
165 endif( LLVM_BUILD_32_BITS )
166 endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
168 # On Win32 using MS tools, provide an option to set the number of parallel jobs
171 set(LLVM_COMPILER_JOBS "0" CACHE STRING
172 "Number of parallel compiler jobs. 0 means use all processors. Default is 0.")
173 if( NOT LLVM_COMPILER_JOBS STREQUAL "1" )
174 if( LLVM_COMPILER_JOBS STREQUAL "0" )
175 add_llvm_definitions( /MP )
179 "Due to a bug in CMake only 0 and 1 is supported for "
180 "LLVM_COMPILER_JOBS when generating for Visual Studio 2010")
182 message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS})
183 add_llvm_definitions( /MP${LLVM_COMPILER_JOBS} )
187 message(STATUS "Parallel compilation disabled")
192 include(ChooseMSVCCRT)
194 if( NOT (${CMAKE_VERSION} VERSION_LESS 2.8.11) )
195 # set stack reserved size to ~10MB
196 # CMake previously automatically set this value for MSVC builds, but the
197 # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default
198 # value (1 MB) which is not enough for us in tasks such as parsing recursive
199 # C++ templates in Clang.
200 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /STACK:10000000")
204 # MSVC 10 will complain about headers in the STL not being exported, but
205 # will not complain in MSVC 11.
206 add_llvm_definitions(
207 -wd4275 # Suppress 'An exported class was derived from a class that was not exported.'
210 add_llvm_definitions(-D_VARIADIC_MAX=10)
213 # Add definitions that make MSVC much less annoying.
214 add_llvm_definitions(
215 # For some reason MS wants to deprecate a bunch of standard functions...
216 -D_CRT_SECURE_NO_DEPRECATE
217 -D_CRT_SECURE_NO_WARNINGS
218 -D_CRT_NONSTDC_NO_DEPRECATE
219 -D_CRT_NONSTDC_NO_WARNINGS
220 -D_SCL_SECURE_NO_DEPRECATE
221 -D_SCL_SECURE_NO_WARNINGS
224 -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned'
225 -wd4180 # Suppress 'qualifier applied to function type has no meaning; ignored'
226 -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data'
227 -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data'
228 -wd4345 # Suppress 'behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized'
229 -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized'
230 -wd4355 # Suppress ''this' : used in base member initializer list'
231 -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated'
232 -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible'
233 -wd4800 # Suppress ''type' : forcing value to bool 'true' or 'false' (performance warning)'
234 -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception'
237 -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning.
239 # Promoted warnings to errors.
240 -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error.
244 if (LLVM_ENABLE_WARNINGS)
245 add_llvm_definitions( /W4 )
246 if (LLVM_ENABLE_PEDANTIC)
247 # No MSVC equivalent available
248 endif (LLVM_ENABLE_PEDANTIC)
249 endif (LLVM_ENABLE_WARNINGS)
250 if (LLVM_ENABLE_WERROR)
251 add_llvm_definitions( /WX )
252 endif (LLVM_ENABLE_WERROR)
253 elseif( LLVM_COMPILER_IS_GCC_COMPATIBLE )
254 if (LLVM_ENABLE_WARNINGS)
255 append("-Wall -W -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
257 # Turn off missing field initializer warnings for gcc to avoid noise from
258 # false positives with empty {}. Turn them on otherwise (they're off by
259 # default for clang).
260 check_cxx_compiler_flag("-Wmissing-field-initializers" CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
261 if (CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
262 if (CMAKE_COMPILER_IS_GNUCXX)
263 append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
265 append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
269 append_if(LLVM_ENABLE_PEDANTIC "-pedantic -Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
270 check_cxx_compiler_flag("-Werror -Wcovered-switch-default" CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG)
271 append_if(CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG "-Wcovered-switch-default" CMAKE_CXX_FLAGS)
272 check_c_compiler_flag("-Werror -Wcovered-switch-default" C_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG)
273 append_if(C_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG "-Wcovered-switch-default" CMAKE_C_FLAGS)
274 append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS)
275 append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS)
276 check_cxx_compiler_flag("-Werror -Wnon-virtual-dtor" CXX_SUPPORTS_NON_VIRTUAL_DTOR_FLAG)
277 append_if(CXX_SUPPORTS_NON_VIRTUAL_DTOR_FLAG "-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
278 endif (LLVM_ENABLE_WARNINGS)
279 if (LLVM_ENABLE_WERROR)
280 add_llvm_definitions( -Werror )
281 endif (LLVM_ENABLE_WERROR)
282 if (LLVM_ENABLE_CXX11)
283 check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11)
284 append_if(CXX_SUPPORTS_CXX11 "-std=c++11" CMAKE_CXX_FLAGS)
285 endif (LLVM_ENABLE_CXX11)
288 macro(append_common_sanitizer_flags)
289 # Append -fno-omit-frame-pointer and turn on debug info to get better
291 add_flag_if_supported("-fno-omit-frame-pointer")
292 if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND
293 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")
294 add_flag_if_supported("-gline-tables-only")
296 # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large.
297 if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
298 add_flag_if_supported("-O1")
302 # Turn on sanitizers if necessary.
303 if(LLVM_USE_SANITIZER)
305 if (LLVM_USE_SANITIZER STREQUAL "Address")
306 append_common_sanitizer_flags()
307 add_flag_or_print_warning("-fsanitize=address")
308 elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?")
309 append_common_sanitizer_flags()
310 add_flag_or_print_warning("-fsanitize=memory")
311 if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins")
312 add_flag_or_print_warning("-fsanitize-memory-track-origins")
315 message(WARNING "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}")
318 message(WARNING "LLVM_USE_SANITIZER is not supported on this platform.")
322 # Turn on -gsplit-dwarf if requested
323 if(LLVM_USE_SPLIT_DWARF)
324 add_llvm_definitions("-gsplit-dwarf")
327 add_llvm_definitions( -D__STDC_CONSTANT_MACROS )
328 add_llvm_definitions( -D__STDC_FORMAT_MACROS )
329 add_llvm_definitions( -D__STDC_LIMIT_MACROS )
331 # clang doesn't print colored diagnostics when invoked from Ninja
333 CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND
334 CMAKE_GENERATOR STREQUAL "Ninja")
335 append("-fcolor-diagnostics" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
338 # Clang prior to 3.5 ignored -fno-function-sections.
339 # It's pretty hard to test directly, so we rely on the version number.
340 if( ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang") AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.5) )
341 set(LLVM_COMPILER_HAS_BROKEN_FNO_FUNCTION_SECTIONS ON)
344 # Add flags for add_dead_strip().
345 # FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF?
346 # But MinSizeRel seems to add that automatically, so maybe disable these
347 # flags instead if LLVM_NO_DEAD_STRIP is set.
348 if(NOT CYGWIN AND NOT WIN32)
349 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
350 # Don't add -ffunction-section if it can be disabled with -fno-function-sections.
351 # Doing so will break sanitizers.
352 if (NOT LLVM_COMPILER_HAS_BROKEN_FNO_FUNCTION_SECTIONS)
353 append("-ffunction-sections -fdata-sections" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
359 # Remove flags here, for exceptions and RTTI.
360 # Each target property or source property should be responsible to control
362 # CL.EXE complains to override flags like "/GR /GR-".
363 string(REGEX REPLACE "(^| ) */EH[-cs]+ *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
364 string(REGEX REPLACE "(^| ) */GR-? *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")