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(HandleLLVMStdlib)
6 include(AddLLVMDefinitions)
7 include(CheckCCompilerFlag)
8 include(CheckCXXCompilerFlag)
10 if(NOT LLVM_FORCE_USE_OLD_TOOLCHAIN)
11 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
12 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.7)
13 message(FATAL_ERROR "Host GCC version must be at least 4.7!")
15 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
16 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.1)
17 message(FATAL_ERROR "Host Clang version must be at least 3.1!")
20 # Also test that we aren't using too old of a version of libstdc++ with the
21 # Clang compiler. This is tricky as there is no real way to check the
22 # version of libstdc++ directly. Instead we test for a known bug in
23 # libstdc++4.6 that is fixed in libstdc++4.7.
24 if(NOT LLVM_ENABLE_LIBCXX)
25 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
26 set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
27 set(CMAKE_REQUIRED_FLAGS "-std=c++0x")
29 set(CMAKE_REQUIRED_LIBRARIES "atomic")
31 check_cxx_source_compiles("
33 std::atomic<float> x(0.0f);
34 int main() { return (float)x; }"
35 LLVM_NO_OLD_LIBSTDCXX)
36 if(NOT LLVM_NO_OLD_LIBSTDCXX)
37 message(FATAL_ERROR "Host Clang must be able to find libstdc++4.7 or newer!")
39 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
40 set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES})
42 elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
43 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 17.0)
44 message(FATAL_ERROR "Host Visual Studio must be at least 2012 (MSVC 17.0)")
49 if( LLVM_ENABLE_ASSERTIONS )
50 # MSVC doesn't like _DEBUG on release builds. See PR 4379.
52 add_definitions( -D_DEBUG )
54 # On non-Debug builds cmake automatically defines NDEBUG, so we
55 # explicitly undefine it:
56 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )
57 add_definitions( -UNDEBUG )
58 # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines.
59 set(REGEXP_NDEBUG "(^| )[/-]D *NDEBUG($| )")
60 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
61 CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE}")
62 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
63 CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
64 string (REGEX REPLACE "${REGEXP_NDEBUG}" " "
65 CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS_MINSIZEREL}")
68 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELEASE" )
69 if( NOT MSVC_IDE AND NOT XCODE )
70 add_definitions( -DNDEBUG )
76 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
84 # Maximum path length is 160 for non-unicode paths
91 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
93 set(LLVM_HAVE_LINK_VERSION_SCRIPT 1)
95 # FIXME: Maximum path length is currently set to 'safe' fixed value
98 MESSAGE(SEND_ERROR "Unable to determine platform")
102 set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX})
103 set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
105 # We use *.dylib rather than *.so on darwin.
106 set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
109 # Darwin-specific linker flags for loadable modules.
110 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-flat_namespace -Wl,-undefined -Wl,suppress")
113 function(add_flag_or_print_warning flag)
114 check_c_compiler_flag(${flag} C_SUPPORTS_FLAG)
115 check_cxx_compiler_flag(${flag} CXX_SUPPORTS_FLAG)
116 if (C_SUPPORTS_FLAG AND CXX_SUPPORTS_FLAG)
117 message(STATUS "Building with ${flag}")
118 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE)
119 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE)
121 message(WARNING "${flag} is not supported.")
125 function(append value)
126 foreach(variable ${ARGN})
127 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
131 function(append_if condition value)
133 foreach(variable ${ARGN})
134 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
139 macro(add_flag_if_supported flag)
140 check_c_compiler_flag(${flag} C_SUPPORTS_FLAG)
141 append_if(C_SUPPORTS_FLAG "${flag}" CMAKE_C_FLAGS)
142 check_cxx_compiler_flag(${flag} CXX_SUPPORTS_FLAG)
143 append_if(CXX_SUPPORTS_FLAG "${flag}" CMAKE_CXX_FLAGS)
146 if( LLVM_ENABLE_PIC )
148 # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
149 # know how to disable this, so just force ENABLE_PIC off for now.
150 message(WARNING "-fPIC not supported with Xcode.")
151 elseif( WIN32 OR CYGWIN)
152 # On Windows all code is PIC. MinGW warns if -fPIC is used.
154 add_flag_or_print_warning("-fPIC")
157 # MinGW warns if -fvisibility-inlines-hidden is used.
159 check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG)
160 append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS)
165 if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
166 # TODO: support other platforms and toolchains.
167 if( LLVM_BUILD_32_BITS )
168 message(STATUS "Building 32 bits executables and libraries.")
169 add_llvm_definitions( -m32 )
170 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32")
171 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32")
172 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32")
173 endif( LLVM_BUILD_32_BITS )
174 endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
176 # On Win32 using MS tools, provide an option to set the number of parallel jobs
179 set(LLVM_COMPILER_JOBS "0" CACHE STRING
180 "Number of parallel compiler jobs. 0 means use all processors. Default is 0.")
181 if( NOT LLVM_COMPILER_JOBS STREQUAL "1" )
182 if( LLVM_COMPILER_JOBS STREQUAL "0" )
183 add_llvm_definitions( /MP )
187 "Due to a bug in CMake only 0 and 1 is supported for "
188 "LLVM_COMPILER_JOBS when generating for Visual Studio 2010")
190 message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS})
191 add_llvm_definitions( /MP${LLVM_COMPILER_JOBS} )
195 message(STATUS "Parallel compilation disabled")
200 include(ChooseMSVCCRT)
202 if( NOT (${CMAKE_VERSION} VERSION_LESS 2.8.11) )
203 # set stack reserved size to ~10MB
204 # CMake previously automatically set this value for MSVC builds, but the
205 # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default
206 # value (1 MB) which is not enough for us in tasks such as parsing recursive
207 # C++ templates in Clang.
208 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /STACK:10000000")
212 # MSVC 10 will complain about headers in the STL not being exported, but
213 # will not complain in MSVC 11.
214 add_llvm_definitions(
215 -wd4275 # Suppress 'An exported class was derived from a class that was not exported.'
218 add_llvm_definitions(-D_VARIADIC_MAX=10)
221 # Add definitions that make MSVC much less annoying.
222 add_llvm_definitions(
223 # For some reason MS wants to deprecate a bunch of standard functions...
224 -D_CRT_SECURE_NO_DEPRECATE
225 -D_CRT_SECURE_NO_WARNINGS
226 -D_CRT_NONSTDC_NO_DEPRECATE
227 -D_CRT_NONSTDC_NO_WARNINGS
228 -D_SCL_SECURE_NO_DEPRECATE
229 -D_SCL_SECURE_NO_WARNINGS
232 -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned'
233 -wd4180 # Suppress 'qualifier applied to function type has no meaning; ignored'
234 -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data'
235 -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data'
236 -wd4345 # Suppress 'behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized'
237 -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized'
238 -wd4355 # Suppress ''this' : used in base member initializer list'
239 -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated'
240 -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible'
241 -wd4800 # Suppress ''type' : forcing value to bool 'true' or 'false' (performance warning)'
242 -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception'
245 -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning.
247 # Promoted warnings to errors.
248 -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error.
252 if (LLVM_ENABLE_WARNINGS)
253 add_llvm_definitions( /W4 )
254 if (LLVM_ENABLE_PEDANTIC)
255 # No MSVC equivalent available
256 endif (LLVM_ENABLE_PEDANTIC)
257 endif (LLVM_ENABLE_WARNINGS)
258 if (LLVM_ENABLE_WERROR)
259 add_llvm_definitions( /WX )
260 endif (LLVM_ENABLE_WERROR)
261 elseif( LLVM_COMPILER_IS_GCC_COMPATIBLE )
262 if (LLVM_ENABLE_WARNINGS)
263 append("-Wall -W -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
265 # Turn off missing field initializer warnings for gcc to avoid noise from
266 # false positives with empty {}. Turn them on otherwise (they're off by
267 # default for clang).
268 check_cxx_compiler_flag("-Wmissing-field-initializers" CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
269 if (CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
270 if (CMAKE_COMPILER_IS_GNUCXX)
271 append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
273 append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
277 append_if(LLVM_ENABLE_PEDANTIC "-pedantic -Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
278 check_cxx_compiler_flag("-Werror -Wcovered-switch-default" CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG)
279 append_if(CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG "-Wcovered-switch-default" CMAKE_CXX_FLAGS)
280 check_c_compiler_flag("-Werror -Wcovered-switch-default" C_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG)
281 append_if(C_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG "-Wcovered-switch-default" CMAKE_C_FLAGS)
282 append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS)
283 append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS)
284 check_cxx_compiler_flag("-Werror -Wnon-virtual-dtor" CXX_SUPPORTS_NON_VIRTUAL_DTOR_FLAG)
285 append_if(CXX_SUPPORTS_NON_VIRTUAL_DTOR_FLAG "-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
286 endif (LLVM_ENABLE_WARNINGS)
287 if (LLVM_ENABLE_WERROR)
288 add_llvm_definitions( -Werror )
289 endif (LLVM_ENABLE_WERROR)
290 if (LLVM_ENABLE_CXX11)
291 check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11)
292 append_if(CXX_SUPPORTS_CXX11 "-std=c++11" CMAKE_CXX_FLAGS)
293 endif (LLVM_ENABLE_CXX11)
296 macro(append_common_sanitizer_flags)
297 # Append -fno-omit-frame-pointer and turn on debug info to get better
299 add_flag_if_supported("-fno-omit-frame-pointer")
300 if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND
301 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")
302 add_flag_if_supported("-gline-tables-only")
304 # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large.
305 if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
306 add_flag_if_supported("-O1")
310 # Turn on sanitizers if necessary.
311 if(LLVM_USE_SANITIZER)
313 if (LLVM_USE_SANITIZER STREQUAL "Address")
314 append_common_sanitizer_flags()
315 add_flag_or_print_warning("-fsanitize=address")
316 elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?")
317 append_common_sanitizer_flags()
318 add_flag_or_print_warning("-fsanitize=memory")
319 if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins")
320 add_flag_or_print_warning("-fsanitize-memory-track-origins")
323 message(WARNING "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}")
326 message(WARNING "LLVM_USE_SANITIZER is not supported on this platform.")
330 # Turn on -gsplit-dwarf if requested
331 if(LLVM_USE_SPLIT_DWARF)
332 add_llvm_definitions("-gsplit-dwarf")
335 add_llvm_definitions( -D__STDC_CONSTANT_MACROS )
336 add_llvm_definitions( -D__STDC_FORMAT_MACROS )
337 add_llvm_definitions( -D__STDC_LIMIT_MACROS )
339 # clang doesn't print colored diagnostics when invoked from Ninja
341 CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND
342 CMAKE_GENERATOR STREQUAL "Ninja")
343 append("-fcolor-diagnostics" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
346 # Add flags for add_dead_strip().
347 # FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF?
348 # But MinSizeRel seems to add that automatically, so maybe disable these
349 # flags instead if LLVM_NO_DEAD_STRIP is set.
350 if(NOT CYGWIN AND NOT WIN32)
351 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
352 check_c_compiler_flag("-Werror -fno-function-sections" C_SUPPORTS_FNO_FUNCTION_SECTIONS)
353 if (C_SUPPORTS_FNO_FUNCTION_SECTIONS)
354 # Don't add -ffunction-section if it can be disabled with -fno-function-sections.
355 # Doing so will break sanitizers.
356 check_c_compiler_flag("-Werror -ffunction-sections" C_SUPPORTS_FFUNCTION_SECTIONS)
357 check_cxx_compiler_flag("-Werror -ffunction-sections" CXX_SUPPORTS_FFUNCTION_SECTIONS)
358 append_if(C_SUPPORTS_FFUNCTION_SECTIONS "-ffunction-sections" CMAKE_C_FLAGS)
359 append_if(CXX_SUPPORTS_FFUNCTION_SECTIONS "-ffunction-sections" CMAKE_CXX_FLAGS)
361 check_c_compiler_flag("-Werror -fdata-sections" C_SUPPORTS_FDATA_SECTIONS)
362 check_cxx_compiler_flag("-Werror -fdata-sections" CXX_SUPPORTS_FDATA_SECTIONS)
363 append_if(C_SUPPORTS_FDATA_SECTIONS "-fdata-sections" CMAKE_C_FLAGS)
364 append_if(CXX_SUPPORTS_FDATA_SECTIONS "-fdata-sections" CMAKE_CXX_FLAGS)
369 # Remove flags here, for exceptions and RTTI.
370 # Each target property or source property should be responsible to control
372 # CL.EXE complains to override flags like "/GR /GR-".
373 string(REGEX REPLACE "(^| ) */EH[-cs]+ *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
374 string(REGEX REPLACE "(^| ) */GR-? *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")