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 # This is commonly needed so make sure it's defined before we include anything
7 string(TOUPPER "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE)
9 include(CheckCompilerVersion)
10 include(HandleLLVMStdlib)
11 include(CheckCCompilerFlag)
12 include(CheckCXXCompilerFlag)
13 include(CheckSymbolExists)
15 if(CMAKE_LINKER MATCHES "lld-link\.exe" OR (WIN32 AND LLVM_USE_LINKER STREQUAL "lld") OR LLVM_ENABLE_LLD)
16 set(LINKER_IS_LLD_LINK TRUE)
18 set(LINKER_IS_LLD_LINK FALSE)
21 set(LLVM_ENABLE_LTO OFF CACHE STRING "Build LLVM with LTO. May be specified as Thin or Full to use a particular kind of LTO")
22 string(TOUPPER "${LLVM_ENABLE_LTO}" uppercase_LLVM_ENABLE_LTO)
24 # Ninja Job Pool support
25 # The following only works with the Ninja generator in CMake >= 3.0.
26 set(LLVM_PARALLEL_COMPILE_JOBS "" CACHE STRING
27 "Define the maximum number of concurrent compilation jobs (Ninja only).")
28 if(LLVM_PARALLEL_COMPILE_JOBS)
29 if(NOT CMAKE_MAKE_PROGRAM MATCHES "ninja")
30 message(WARNING "Job pooling is only available with Ninja generators.")
32 set_property(GLOBAL APPEND PROPERTY JOB_POOLS compile_job_pool=${LLVM_PARALLEL_COMPILE_JOBS})
33 set(CMAKE_JOB_POOL_COMPILE compile_job_pool)
37 set(LLVM_PARALLEL_LINK_JOBS "" CACHE STRING
38 "Define the maximum number of concurrent link jobs (Ninja only).")
39 if(CMAKE_MAKE_PROGRAM MATCHES "ninja")
40 if(NOT LLVM_PARALLEL_LINK_JOBS AND uppercase_LLVM_ENABLE_LTO STREQUAL "THIN")
41 message(STATUS "ThinLTO provides its own parallel linking - limiting parallel link jobs to 2.")
42 set(LLVM_PARALLEL_LINK_JOBS "2")
44 if(LLVM_PARALLEL_LINK_JOBS)
45 set_property(GLOBAL APPEND PROPERTY JOB_POOLS link_job_pool=${LLVM_PARALLEL_LINK_JOBS})
46 set(CMAKE_JOB_POOL_LINK link_job_pool)
48 elseif(LLVM_PARALLEL_LINK_JOBS)
49 message(WARNING "Job pooling is only available with Ninja generators.")
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 foreach (flags_var_to_scrub
63 CMAKE_CXX_FLAGS_RELEASE
64 CMAKE_CXX_FLAGS_RELWITHDEBINFO
65 CMAKE_CXX_FLAGS_MINSIZEREL
67 CMAKE_C_FLAGS_RELWITHDEBINFO
68 CMAKE_C_FLAGS_MINSIZEREL)
69 string (REGEX REPLACE "(^| )[/-]D *NDEBUG($| )" " "
70 "${flags_var_to_scrub}" "${${flags_var_to_scrub}}")
75 if(LLVM_ENABLE_EXPENSIVE_CHECKS)
76 add_definitions(-DEXPENSIVE_CHECKS)
77 add_definitions(-D_GLIBCXX_DEBUG)
80 string(TOUPPER "${LLVM_ABI_BREAKING_CHECKS}" uppercase_LLVM_ABI_BREAKING_CHECKS)
82 if( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "WITH_ASSERTS" )
83 if( LLVM_ENABLE_ASSERTIONS )
84 set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 )
86 elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_ON" )
87 set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 )
88 elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_OFF" )
89 # We don't need to do anything special to turn off ABI breaking checks.
90 elseif( NOT DEFINED LLVM_ABI_BREAKING_CHECKS )
91 # Treat LLVM_ABI_BREAKING_CHECKS like "FORCE_OFF" when it has not been
94 message(FATAL_ERROR "Unknown value for LLVM_ABI_BREAKING_CHECKS: \"${LLVM_ABI_BREAKING_CHECKS}\"!")
97 if( LLVM_REVERSE_ITERATION )
98 set( LLVM_ENABLE_REVERSE_ITERATION 1 )
102 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
114 if(APPLE OR ${CMAKE_SYSTEM_NAME} MATCHES "AIX")
115 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
117 set(LLVM_HAVE_LINK_VERSION_SCRIPT 1)
119 else(FUCHSIA OR UNIX)
120 MESSAGE(SEND_ERROR "Unable to determine platform")
121 endif(FUCHSIA OR UNIX)
124 set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX})
125 set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
127 # We use *.dylib rather than *.so on darwin.
128 set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
131 if(LLVM_ENABLE_LLD AND LLVM_ENABLE_LTO)
132 message(FATAL_ERROR "lld does not support LTO on Darwin")
134 # Darwin-specific linker flags for loadable modules.
135 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-flat_namespace -Wl,-undefined -Wl,suppress")
138 if(${CMAKE_SYSTEM_NAME} MATCHES "AIX")
139 if(NOT LLVM_BUILD_32_BITS)
140 if (CMAKE_CXX_COMPILER_ID MATCHES "XL")
141 append("-q64" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
143 append("-maix64" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
145 set(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> -X64 qc <TARGET> <LINK_FLAGS> <OBJECTS>")
146 set(CMAKE_CXX_ARCHIVE_APPEND "<CMAKE_AR> -X64 q <TARGET> <LINK_FLAGS> <OBJECTS>")
147 set(CMAKE_C_ARCHIVE_FINISH "<CMAKE_RANLIB> -X64 <TARGET>")
148 set(CMAKE_CXX_ARCHIVE_FINISH "<CMAKE_RANLIB> -X64 <TARGET>")
150 # -fPIC does not enable the large code model for GCC on AIX but does for XL.
151 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
152 append("-mcmodel=large" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
153 elseif(CMAKE_CXX_COMPILER_ID MATCHES "XL")
154 # XL generates a small number of relocations not of the large model, -bbigtoc is needed.
155 append("-Wl,-bbigtoc"
156 CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
160 # Pass -Wl,-z,defs. This makes sure all symbols are defined. Otherwise a DSO
161 # build might work on ELF but fail on MachO/COFF.
162 if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin|FreeBSD|OpenBSD|DragonFly|AIX" OR
164 NOT LLVM_USE_SANITIZER)
165 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,defs")
168 # Pass -Wl,-z,nodelete. This makes sure our shared libraries are not unloaded
169 # by dlclose(). We need that since the CLI API relies on cross-references
170 # between global objects which became horribly broken when one of the libraries
172 if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
173 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,nodelete")
174 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-z,nodelete")
178 function(append value)
179 foreach(variable ${ARGN})
180 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
184 function(append_if condition value)
186 foreach(variable ${ARGN})
187 set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
192 macro(add_flag_if_supported flag name)
193 check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}")
194 append_if("C_SUPPORTS_${name}" "${flag}" CMAKE_C_FLAGS)
195 check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}")
196 append_if("CXX_SUPPORTS_${name}" "${flag}" CMAKE_CXX_FLAGS)
199 function(add_flag_or_print_warning flag name)
200 check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}")
201 check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}")
202 if (C_SUPPORTS_${name} AND CXX_SUPPORTS_${name})
203 message(STATUS "Building with ${flag}")
204 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE)
205 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE)
206 set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${flag}" PARENT_SCOPE)
208 message(WARNING "${flag} is not supported.")
212 if( LLVM_ENABLE_LLD )
213 if ( LLVM_USE_LINKER )
214 message(FATAL_ERROR "LLVM_ENABLE_LLD and LLVM_USE_LINKER can't be set at the same time")
216 set(LLVM_USE_LINKER "lld")
219 if( LLVM_USE_LINKER )
220 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
221 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -fuse-ld=${LLVM_USE_LINKER}")
222 check_cxx_source_compiles("int main() { return 0; }" CXX_SUPPORTS_CUSTOM_LINKER)
223 if ( NOT CXX_SUPPORTS_CUSTOM_LINKER )
224 message(FATAL_ERROR "Host compiler does not support '-fuse-ld=${LLVM_USE_LINKER}'")
226 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
227 append("-fuse-ld=${LLVM_USE_LINKER}"
228 CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
231 if( LLVM_ENABLE_PIC )
233 # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
234 # know how to disable this, so just force ENABLE_PIC off for now.
235 message(WARNING "-fPIC not supported with Xcode.")
236 elseif( WIN32 OR CYGWIN)
237 # On Windows all code is PIC. MinGW warns if -fPIC is used.
239 add_flag_or_print_warning("-fPIC" FPIC)
243 if(NOT WIN32 AND NOT CYGWIN AND NOT (${CMAKE_SYSTEM_NAME} MATCHES "AIX" AND CMAKE_CXX_COMPILER_ID STREQUAL "GNU"))
244 # MinGW warns if -fvisibility-inlines-hidden is used.
245 # GCC on AIX warns if -fvisibility-inlines-hidden is used.
246 check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG)
247 append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS)
250 if(CMAKE_SIZEOF_VOID_P EQUAL 8 AND MINGW)
251 add_definitions( -D_FILE_OFFSET_BITS=64 )
254 if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
255 # TODO: support other platforms and toolchains.
256 if( LLVM_BUILD_32_BITS )
257 message(STATUS "Building 32 bits executables and libraries.")
258 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -m32")
259 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -m32")
260 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32")
261 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32")
262 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32")
264 # FIXME: CMAKE_SIZEOF_VOID_P is still 8
265 add_definitions(-D_LARGEFILE_SOURCE)
266 add_definitions(-D_FILE_OFFSET_BITS=64)
267 endif( LLVM_BUILD_32_BITS )
268 endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
270 # If building on a GNU specific 32-bit system, make sure off_t is 64 bits
271 # so that off_t can stored offset > 2GB.
272 # Android until version N (API 24) doesn't support it.
273 if (ANDROID AND (ANDROID_NATIVE_API_LEVEL LESS 24))
274 set(LLVM_FORCE_SMALLFILE_FOR_ANDROID TRUE)
276 if( CMAKE_SIZEOF_VOID_P EQUAL 4 AND NOT LLVM_FORCE_SMALLFILE_FOR_ANDROID)
277 # FIXME: It isn't handled in LLVM_BUILD_32_BITS.
278 add_definitions( -D_LARGEFILE_SOURCE )
279 add_definitions( -D_FILE_OFFSET_BITS=64 )
283 # For Xcode enable several build settings that correspond to
284 # many warnings that are on by default in Clang but are
285 # not enabled for historical reasons. For versions of Xcode
286 # that do not support these options they will simply
288 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_RETURN_TYPE "YES")
289 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_MISSING_NEWLINE "YES")
290 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VALUE "YES")
291 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VARIABLE "YES")
292 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_SIGN_COMPARE "YES")
293 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_FUNCTION "YES")
294 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_INITIALIZER_NOT_FULLY_BRACKETED "YES")
295 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_HIDDEN_VIRTUAL_FUNCTIONS "YES")
296 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNINITIALIZED_AUTOS "YES")
297 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_BOOL_CONVERSION "YES")
298 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_EMPTY_BODY "YES")
299 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_ENUM_CONVERSION "YES")
300 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_INT_CONVERSION "YES")
301 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_CONSTANT_CONVERSION "YES")
302 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_NON_VIRTUAL_DESTRUCTOR "YES")
305 # On Win32 using MS tools, provide an option to set the number of parallel jobs
308 set(LLVM_COMPILER_JOBS "0" CACHE STRING
309 "Number of parallel compiler jobs. 0 means use all processors. Default is 0.")
310 if( NOT LLVM_COMPILER_JOBS STREQUAL "1" )
311 if( LLVM_COMPILER_JOBS STREQUAL "0" )
312 add_definitions( /MP )
314 message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS})
315 add_definitions( /MP${LLVM_COMPILER_JOBS} )
318 message(STATUS "Parallel compilation disabled")
322 # set stack reserved size to ~10MB
324 # CMake previously automatically set this value for MSVC builds, but the
325 # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default
326 # value (1 MB) which is not enough for us in tasks such as parsing recursive
327 # C++ templates in Clang.
328 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /STACK:10000000")
329 elseif(MINGW) # FIXME: Also cygwin?
330 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--stack,16777216")
332 # Pass -mbig-obj to mingw gas on Win64. COFF has a 2**16 section limit, and
333 # on Win64, every COMDAT function creates at least 3 sections: .text, .pdata,
335 if (CMAKE_SIZEOF_VOID_P EQUAL 8)
336 append("-Wa,-mbig-obj" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
341 if( CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.0 )
342 # For MSVC 2013, disable iterator null pointer checking in debug mode,
343 # especially so std::equal(nullptr, nullptr, nullptr) will not assert.
344 add_definitions("-D_DEBUG_POINTER_IMPL=")
347 include(ChooseMSVCCRT)
350 add_definitions(-D_VARIADIC_MAX=10)
353 # Add definitions that make MSVC much less annoying.
355 # For some reason MS wants to deprecate a bunch of standard functions...
356 -D_CRT_SECURE_NO_DEPRECATE
357 -D_CRT_SECURE_NO_WARNINGS
358 -D_CRT_NONSTDC_NO_DEPRECATE
359 -D_CRT_NONSTDC_NO_WARNINGS
360 -D_SCL_SECURE_NO_DEPRECATE
361 -D_SCL_SECURE_NO_WARNINGS
364 # Tell MSVC to use the Unicode version of the Win32 APIs instead of ANSI.
370 if (LLVM_ENABLE_WERROR)
371 append("/WX" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
372 endif (LLVM_ENABLE_WERROR)
374 append("/Zc:inline" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
376 # Allow users to request PDBs in release mode. CMake offeres the
377 # RelWithDebInfo configuration, but it uses different optimization settings
378 # (/Ob1 vs /Ob2 or -O2 vs -O3). LLVM provides this flag so that users can get
379 # PDBs without changing codegen.
380 option(LLVM_ENABLE_PDB OFF)
381 if (LLVM_ENABLE_PDB AND uppercase_CMAKE_BUILD_TYPE STREQUAL "RELEASE")
382 append("/Zi" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
383 # /DEBUG disables linker GC and ICF, but we want those in Release mode.
384 append("/DEBUG /OPT:REF /OPT:ICF"
385 CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS
386 CMAKE_SHARED_LINKER_FLAGS)
389 # /Zc:strictStrings is incompatible with VS12's (Visual Studio 2013's)
390 # debug mode headers. Instead of only enabling them in VS2013's debug mode,
391 # we'll just enable them for Visual Studio 2015 (VS 14, MSVC_VERSION 1900)
393 if (NOT (MSVC_VERSION LESS 1900))
394 # Disable string literal const->non-const type conversion.
395 # "When specified, the compiler requires strict const-qualification
396 # conformance for pointers initialized by using string literals."
397 append("/Zc:strictStrings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
398 endif(NOT (MSVC_VERSION LESS 1900))
400 # "Generate Intrinsic Functions".
401 append("/Oi" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
403 # "Enforce type conversion rules".
404 append("/Zc:rvalueCast" CMAKE_CXX_FLAGS)
406 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT LLVM_ENABLE_LTO)
407 # clang-cl and cl by default produce non-deterministic binaries because
408 # link.exe /incremental requires a timestamp in the .obj file. clang-cl
409 # has the flag /Brepro to force deterministic binaries. We want to pass that
410 # whenever you're building with clang unless you're passing /incremental
411 # or using LTO (/Brepro with LTO would result in a warning about the flag
412 # being unused, because we're not generating object files).
413 # This checks CMAKE_CXX_COMPILER_ID in addition to check_cxx_compiler_flag()
414 # because cl.exe does not emit an error on flags it doesn't understand,
415 # letting check_cxx_compiler_flag() claim it understands all flags.
416 check_cxx_compiler_flag("/Brepro" SUPPORTS_BREPRO)
418 # Check if /INCREMENTAL is passed to the linker and complain that it
419 # won't work with /Brepro.
420 string(TOUPPER "${CMAKE_EXE_LINKER_FLAGS}" upper_exe_flags)
421 string(TOUPPER "${CMAKE_MODULE_LINKER_FLAGS}" upper_module_flags)
422 string(TOUPPER "${CMAKE_SHARED_LINKER_FLAGS}" upper_shared_flags)
424 string(FIND "${upper_exe_flags} ${upper_module_flags} ${upper_shared_flags}"
425 "/INCREMENTAL" linker_flag_idx)
427 if (${linker_flag_idx} GREATER -1)
428 message(WARNING "/Brepro not compatible with /INCREMENTAL linking - builds will be non-deterministic")
430 append("/Brepro" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
435 elseif( LLVM_COMPILER_IS_GCC_COMPATIBLE )
436 append_if(LLVM_ENABLE_WERROR "-Werror" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
437 append_if(LLVM_ENABLE_WERROR "-Wno-error" CMAKE_REQUIRED_FLAGS)
438 add_flag_if_supported("-Werror=date-time" WERROR_DATE_TIME)
439 add_flag_if_supported("-Werror=unguarded-availability-new" WERROR_UNGUARDED_AVAILABILITY_NEW)
440 if (LLVM_ENABLE_CXX1Y)
441 check_cxx_compiler_flag("-std=c++1y" CXX_SUPPORTS_CXX1Y)
442 append_if(CXX_SUPPORTS_CXX1Y "-std=c++1y" CMAKE_CXX_FLAGS)
443 elseif(LLVM_ENABLE_CXX1Z)
444 check_cxx_compiler_flag("-std=c++1z" CXX_SUPPORTS_CXX1Z)
445 append_if(CXX_SUPPORTS_CXX1Z "-std=c++1z" CMAKE_CXX_FLAGS)
447 check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11)
448 if (CXX_SUPPORTS_CXX11)
450 # MinGW and Cygwin are a bit stricter and lack things like
451 # 'strdup', 'stricmp', etc in c++11 mode.
452 append("-std=gnu++11" CMAKE_CXX_FLAGS)
454 append("-std=c++11" CMAKE_CXX_FLAGS)
457 message(FATAL_ERROR "LLVM requires C++11 support but the '-std=c++11' flag isn't supported.")
460 if (LLVM_ENABLE_MODULES)
461 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
462 set(module_flags "-fmodules -fmodules-cache-path=${PROJECT_BINARY_DIR}/module.cache")
463 if (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
464 # On Darwin -fmodules does not imply -fcxx-modules.
465 set(module_flags "${module_flags} -fcxx-modules")
467 if (LLVM_ENABLE_LOCAL_SUBMODULE_VISIBILITY)
468 set(module_flags "${module_flags} -Xclang -fmodules-local-submodule-visibility")
470 if (LLVM_ENABLE_MODULE_DEBUGGING AND
471 ((uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") OR
472 (uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")))
473 set(module_flags "${module_flags} -gmodules")
475 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${module_flags}")
477 # Check that we can build code with modules enabled, and that repeatedly
478 # including <cassert> still manages to respect NDEBUG properly.
479 CHECK_CXX_SOURCE_COMPILES("#undef NDEBUG
483 int main() { assert(this code is not compiled); }"
484 CXX_SUPPORTS_MODULES)
485 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
486 if (CXX_SUPPORTS_MODULES)
487 append("${module_flags}" CMAKE_CXX_FLAGS)
489 message(FATAL_ERROR "LLVM_ENABLE_MODULES is not supported by this compiler")
491 endif(LLVM_ENABLE_MODULES)
496 set(msvc_warning_flags
498 -wd4141 # Suppress ''modifier' : used more than once' (because of __forceinline combined with inline)
499 -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned'
500 -wd4180 # Suppress 'qualifier applied to function type has no meaning; ignored'
501 -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data'
502 -wd4258 # Suppress ''var' : definition from the for loop is ignored; the definition from the enclosing scope is used'
503 -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data'
504 -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception'
505 -wd4345 # Suppress 'behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized'
506 -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized'
507 -wd4355 # Suppress ''this' : used in base member initializer list'
508 -wd4456 # Suppress 'declaration of 'var' hides local variable'
509 -wd4457 # Suppress 'declaration of 'var' hides function parameter'
510 -wd4458 # Suppress 'declaration of 'var' hides class member'
511 -wd4459 # Suppress 'declaration of 'var' hides global declaration'
512 -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated'
513 -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible'
514 -wd4722 # Suppress 'function' : destructor never returns, potential memory leak
515 -wd4800 # Suppress ''type' : forcing value to bool 'true' or 'false' (performance warning)'
516 -wd4100 # Suppress 'unreferenced formal parameter'
517 -wd4127 # Suppress 'conditional expression is constant'
518 -wd4512 # Suppress 'assignment operator could not be generated'
519 -wd4505 # Suppress 'unreferenced local function has been removed'
520 -wd4610 # Suppress '<class> can never be instantiated'
521 -wd4510 # Suppress 'default constructor could not be generated'
522 -wd4702 # Suppress 'unreachable code'
523 -wd4245 # Suppress 'signed/unsigned mismatch'
524 -wd4706 # Suppress 'assignment within conditional expression'
525 -wd4310 # Suppress 'cast truncates constant value'
526 -wd4701 # Suppress 'potentially uninitialized local variable'
527 -wd4703 # Suppress 'potentially uninitialized local pointer variable'
528 -wd4389 # Suppress 'signed/unsigned mismatch'
529 -wd4611 # Suppress 'interaction between '_setjmp' and C++ object destruction is non-portable'
530 -wd4805 # Suppress 'unsafe mix of type <type> and type <type> in operation'
531 -wd4204 # Suppress 'nonstandard extension used : non-constant aggregate initializer'
532 -wd4577 # Suppress 'noexcept used with no exception handling mode specified; termination on exception is not guaranteed'
533 -wd4091 # Suppress 'typedef: ignored on left of '' when no variable is declared'
534 # C4592 is disabled because of false positives in Visual Studio 2015
535 # Update 1. Re-evaluate the usefulness of this diagnostic with Update 2.
536 -wd4592 # Suppress ''var': symbol will be dynamically initialized (implementation limitation)
537 -wd4319 # Suppress ''operator' : zero extending 'type' to 'type' of greater size'
538 # C4709 is disabled because of a bug with Visual Studio 2017 as of
539 # v15.8.8. Re-evaluate the usefulness of this diagnostic when the bug
541 -wd4709 # Suppress comma operator within array index expression
543 # Ideally, we'd like this warning to be enabled, but MSVC 2013 doesn't
544 # support the 'aligned' attribute in the way that clang sources requires (for
545 # any code that uses the LLVM_ALIGNAS macro), so this is must be disabled to
546 # avoid unwanted alignment warnings.
547 # When we switch to requiring a version of MSVC that supports the 'alignas'
548 # specifier (MSVC 2015?) this warning can be re-enabled.
549 -wd4324 # Suppress 'structure was padded due to __declspec(align())'
552 -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning.
554 # Promoted warnings to errors.
555 -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error.
560 if (LLVM_ENABLE_WARNINGS)
561 # Put /W4 in front of all the -we flags. cl.exe doesn't care, but for
562 # clang-cl having /W4 after the -we flags will re-enable the warnings
564 set(msvc_warning_flags "/W4 ${msvc_warning_flags}")
565 # CMake appends /W3 by default, and having /W3 followed by /W4 will result in
566 # cl : Command line warning D9025 : overriding '/W3' with '/W4'. Since this is
567 # a command line warning and not a compiler warning, it cannot be suppressed except
568 # by fixing the command line.
569 string(REGEX REPLACE " /W[0-4]" "" CMAKE_C_FLAGS "${CMAKE_C_FLAGS}")
570 string(REGEX REPLACE " /W[0-4]" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
572 if (LLVM_ENABLE_PEDANTIC)
573 # No MSVC equivalent available
574 endif (LLVM_ENABLE_PEDANTIC)
575 endif (LLVM_ENABLE_WARNINGS)
577 foreach(flag ${msvc_warning_flags})
578 append("${flag}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
582 if (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
584 # Don't add -Wall for clang-cl, because it maps -Wall to -Weverything for
585 # MSVC compatibility. /W4 is added above instead.
587 append("-Wall" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
590 append("-Wextra -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
591 append("-Wcast-qual" CMAKE_CXX_FLAGS)
593 # Turn off missing field initializer warnings for gcc to avoid noise from
594 # false positives with empty {}. Turn them on otherwise (they're off by
595 # default for clang).
596 check_cxx_compiler_flag("-Wmissing-field-initializers" CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
597 if (CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
598 if (CMAKE_COMPILER_IS_GNUCXX)
599 append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
601 append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
605 if (LLVM_ENABLE_PEDANTIC AND LLVM_COMPILER_IS_GCC_COMPATIBLE)
606 append("-pedantic" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
607 append("-Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
610 add_flag_if_supported("-Wimplicit-fallthrough" IMPLICIT_FALLTHROUGH_FLAG)
611 add_flag_if_supported("-Wcovered-switch-default" COVERED_SWITCH_DEFAULT_FLAG)
612 append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS)
613 append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS)
615 # Disable -Wclass-memaccess, a C++-only warning from GCC 8 that fires on
616 # LLVM's ADT classes.
617 check_cxx_compiler_flag("-Wclass-memaccess" CXX_SUPPORTS_CLASS_MEMACCESS_FLAG)
618 append_if(CXX_SUPPORTS_CLASS_MEMACCESS_FLAG "-Wno-class-memaccess" CMAKE_CXX_FLAGS)
620 # The LLVM libraries have no stable C++ API, so -Wnoexcept-type is not useful.
621 check_cxx_compiler_flag("-Wnoexcept-type" CXX_SUPPORTS_NOEXCEPT_TYPE_FLAG)
622 append_if(CXX_SUPPORTS_NOEXCEPT_TYPE_FLAG "-Wno-noexcept-type" CMAKE_CXX_FLAGS)
624 # Check if -Wnon-virtual-dtor warns even though the class is marked final.
625 # If it does, don't add it. So it won't be added on clang 3.4 and older.
626 # This also catches cases when -Wnon-virtual-dtor isn't supported by
627 # the compiler at all. This flag is not activated for gcc since it will
628 # incorrectly identify a protected non-virtual base when there is a friend
629 # declaration. Don't activate this in general on Windows as this warning has
630 # too many false positives on COM-style classes, which are destroyed with
631 # Release() (PR32286).
632 if (NOT CMAKE_COMPILER_IS_GNUCXX AND NOT WIN32)
633 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
634 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++11 -Werror=non-virtual-dtor")
635 CHECK_CXX_SOURCE_COMPILES("class base {public: virtual void anchor();protected: ~base();};
636 class derived final : public base { public: ~derived();};
637 int main() { return 0; }"
638 CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR)
639 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
640 append_if(CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR
641 "-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
644 # Enable -Wdelete-non-virtual-dtor if available.
645 add_flag_if_supported("-Wdelete-non-virtual-dtor" DELETE_NON_VIRTUAL_DTOR_FLAG)
647 # Check if -Wcomment is OK with an // comment ending with '\' if the next
648 # line is also a // comment.
649 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
650 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror -Wcomment")
651 CHECK_C_SOURCE_COMPILES("// \\\\\\n//\\nint main() {return 0;}"
652 C_WCOMMENT_ALLOWS_LINE_WRAP)
653 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
654 if (NOT C_WCOMMENT_ALLOWS_LINE_WRAP)
655 append("-Wno-comment" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
658 # Enable -Wstring-conversion to catch misuse of string literals.
659 add_flag_if_supported("-Wstring-conversion" STRING_CONVERSION_FLAG)
660 endif (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
662 if (LLVM_COMPILER_IS_GCC_COMPATIBLE AND NOT LLVM_ENABLE_WARNINGS)
663 append("-w" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
666 macro(append_common_sanitizer_flags)
668 # Append -fno-omit-frame-pointer and turn on debug info to get better
670 add_flag_if_supported("-fno-omit-frame-pointer" FNO_OMIT_FRAME_POINTER)
671 if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND
672 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")
673 add_flag_if_supported("-gline-tables-only" GLINE_TABLES_ONLY)
675 # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large.
676 if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND LLVM_OPTIMIZE_SANITIZED_BUILDS)
677 add_flag_if_supported("-O1" O1)
680 # Keep frame pointers around.
681 append("/Oy-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
682 if (LINKER_IS_LLD_LINK)
683 # Use DWARF debug info with LLD.
684 append("-gdwarf" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
686 # Enable codeview otherwise.
687 append("/Z7" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
689 # Always ask the linker to produce symbols with asan.
690 append("-debug" CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
694 # Turn on sanitizers if necessary.
695 if(LLVM_USE_SANITIZER)
697 if (LLVM_USE_SANITIZER STREQUAL "Address")
698 append_common_sanitizer_flags()
699 append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
700 elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?")
701 append_common_sanitizer_flags()
702 append("-fsanitize=memory" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
703 if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins")
704 append("-fsanitize-memory-track-origins" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
706 elseif (LLVM_USE_SANITIZER STREQUAL "Undefined")
707 append_common_sanitizer_flags()
708 append("-fsanitize=undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all"
709 CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
710 elseif (LLVM_USE_SANITIZER STREQUAL "Thread")
711 append_common_sanitizer_flags()
712 append("-fsanitize=thread" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
713 elseif (LLVM_USE_SANITIZER STREQUAL "Address;Undefined" OR
714 LLVM_USE_SANITIZER STREQUAL "Undefined;Address")
715 append_common_sanitizer_flags()
716 append("-fsanitize=address,undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all"
717 CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
718 elseif (LLVM_USE_SANITIZER STREQUAL "Leaks")
719 append_common_sanitizer_flags()
720 append("-fsanitize=leak" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
722 message(FATAL_ERROR "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}")
725 if (LLVM_USE_SANITIZER STREQUAL "Address")
726 append_common_sanitizer_flags()
727 append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
729 message(FATAL_ERROR "This sanitizer not yet supported in the MSVC environment: ${LLVM_USE_SANITIZER}")
732 message(FATAL_ERROR "LLVM_USE_SANITIZER is not supported on this platform.")
734 if (LLVM_USE_SANITIZER MATCHES "(Undefined;)?Address(;Undefined)?")
735 add_flag_if_supported("-fsanitize-address-use-after-scope"
736 FSANITIZE_USE_AFTER_SCOPE_FLAG)
738 if (LLVM_USE_SANITIZE_COVERAGE)
739 append("-fsanitize=fuzzer-no-link" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
741 if (LLVM_USE_SANITIZER MATCHES ".*Undefined.*")
742 set(BLACKLIST_FILE "${CMAKE_SOURCE_DIR}/utils/sanitizers/ubsan_blacklist.txt")
743 if (EXISTS "${BLACKLIST_FILE}")
744 append("-fsanitize-blacklist=${BLACKLIST_FILE}"
745 CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
750 # Turn on -gsplit-dwarf if requested
751 if(LLVM_USE_SPLIT_DWARF)
752 add_definitions("-gsplit-dwarf")
755 add_definitions( -D__STDC_CONSTANT_MACROS )
756 add_definitions( -D__STDC_FORMAT_MACROS )
757 add_definitions( -D__STDC_LIMIT_MACROS )
759 # clang and gcc don't default-print colored diagnostics when invoked from Ninja.
761 CMAKE_GENERATOR STREQUAL "Ninja" AND
762 (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR
763 (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
764 NOT (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9))))
765 append("-fdiagnostics-color" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
768 # lld doesn't print colored diagnostics when invoked from Ninja
769 if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja")
770 include(CheckLinkerFlag)
771 check_linker_flag("-Wl,--color-diagnostics" LINKER_SUPPORTS_COLOR_DIAGNOSTICS)
772 append_if(LINKER_SUPPORTS_COLOR_DIAGNOSTICS "-Wl,--color-diagnostics"
773 CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
776 # Add flags for add_dead_strip().
777 # FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF?
778 # But MinSizeRel seems to add that automatically, so maybe disable these
779 # flags instead if LLVM_NO_DEAD_STRIP is set.
780 if(NOT CYGWIN AND NOT WIN32)
781 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin" AND
782 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
783 check_c_compiler_flag("-Werror -fno-function-sections" C_SUPPORTS_FNO_FUNCTION_SECTIONS)
784 if (C_SUPPORTS_FNO_FUNCTION_SECTIONS)
785 # Don't add -ffunction-section if it can be disabled with -fno-function-sections.
786 # Doing so will break sanitizers.
787 add_flag_if_supported("-ffunction-sections" FFUNCTION_SECTIONS)
789 add_flag_if_supported("-fdata-sections" FDATA_SECTIONS)
794 # Remove flags here, for exceptions and RTTI.
795 # Each target property or source property should be responsible to control
797 # CL.EXE complains to override flags like "/GR /GR-".
798 string(REGEX REPLACE "(^| ) */EH[-cs]+ *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
799 string(REGEX REPLACE "(^| ) */GR-? *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
802 # Provide public options to globally control RTTI and EH
803 option(LLVM_ENABLE_EH "Enable Exception handling" OFF)
804 option(LLVM_ENABLE_RTTI "Enable run time type information" OFF)
805 if(LLVM_ENABLE_EH AND NOT LLVM_ENABLE_RTTI)
806 message(FATAL_ERROR "Exception handling requires RTTI. You must set LLVM_ENABLE_RTTI to ON")
809 option(LLVM_USE_NEWPM "Build LLVM using the experimental new pass manager" Off)
810 mark_as_advanced(LLVM_USE_NEWPM)
812 append("-fexperimental-new-pass-manager"
815 CMAKE_EXE_LINKER_FLAGS
816 CMAKE_SHARED_LINKER_FLAGS)
819 option(LLVM_ENABLE_IR_PGO "Build LLVM and tools with IR PGO instrumentation (deprecated)" Off)
820 mark_as_advanced(LLVM_ENABLE_IR_PGO)
822 set(LLVM_BUILD_INSTRUMENTED OFF CACHE STRING "Build LLVM and tools with PGO instrumentation. May be specified as IR or Frontend")
823 mark_as_advanced(LLVM_BUILD_INSTRUMENTED)
824 string(TOUPPER "${LLVM_BUILD_INSTRUMENTED}" uppercase_LLVM_BUILD_INSTRUMENTED)
826 if (LLVM_BUILD_INSTRUMENTED)
827 if (LLVM_ENABLE_IR_PGO OR uppercase_LLVM_BUILD_INSTRUMENTED STREQUAL "IR")
828 append("-fprofile-generate='${LLVM_PROFILE_DATA_DIR}'"
831 CMAKE_EXE_LINKER_FLAGS
832 CMAKE_SHARED_LINKER_FLAGS)
833 elseif(uppercase_LLVM_BUILD_INSTRUMENTED STREQUAL "CSIR")
834 append("-fcs-profile-generate='${LLVM_CSPROFILE_DATA_DIR}'"
837 CMAKE_EXE_LINKER_FLAGS
838 CMAKE_SHARED_LINKER_FLAGS)
840 append("-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}'"
843 CMAKE_EXE_LINKER_FLAGS
844 CMAKE_SHARED_LINKER_FLAGS)
848 # Need to pass -fprofile-instr-use to linker for context-sensitive PGO
850 if(LLVM_PROFDATA_FILE AND EXISTS ${LLVM_PROFDATA_FILE})
851 append("-fprofile-instr-use='${LLVM_PROFDATA_FILE}'"
852 CMAKE_EXE_LINKER_FLAGS
853 CMAKE_SHARED_LINKER_FLAGS)
856 option(LLVM_BUILD_INSTRUMENTED_COVERAGE "Build LLVM and tools with Code Coverage instrumentation" Off)
857 mark_as_advanced(LLVM_BUILD_INSTRUMENTED_COVERAGE)
858 append_if(LLVM_BUILD_INSTRUMENTED_COVERAGE "-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}' -fcoverage-mapping"
861 CMAKE_EXE_LINKER_FLAGS
862 CMAKE_SHARED_LINKER_FLAGS)
864 if (LLVM_BUILD_INSTRUMENTED AND LLVM_BUILD_INSTRUMENTED_COVERAGE)
865 message(FATAL_ERROR "LLVM_BUILD_INSTRUMENTED and LLVM_BUILD_INSTRUMENTED_COVERAGE cannot both be specified")
868 if(LLVM_ENABLE_LTO AND LLVM_ON_WIN32 AND NOT LINKER_IS_LLD_LINK)
869 message(FATAL_ERROR "When compiling for Windows, LLVM_ENABLE_LTO requires using lld as the linker (point CMAKE_LINKER at lld-link.exe)")
871 if(uppercase_LLVM_ENABLE_LTO STREQUAL "THIN")
872 append("-flto=thin" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
873 if(NOT LINKER_IS_LLD_LINK)
874 append("-flto=thin" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
876 # If the linker supports it, enable the lto cache. This improves initial build
877 # time a little since we re-link a lot of the same objects, and significantly
878 # improves incremental build time.
879 # FIXME: We should move all this logic into the clang driver.
881 append("-Wl,-cache_path_lto,${PROJECT_BINARY_DIR}/lto.cache"
882 CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
883 elseif(UNIX AND LLVM_USE_LINKER STREQUAL "lld")
884 append("-Wl,--thinlto-cache-dir=${PROJECT_BINARY_DIR}/lto.cache"
885 CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
886 elseif(LLVM_USE_LINKER STREQUAL "gold")
887 append("-Wl,--plugin-opt,cache-dir=${PROJECT_BINARY_DIR}/lto.cache"
888 CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
890 elseif(uppercase_LLVM_ENABLE_LTO STREQUAL "FULL")
891 append("-flto=full" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
892 if(NOT LINKER_IS_LLD_LINK)
893 append("-flto=full" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
895 elseif(LLVM_ENABLE_LTO)
896 append("-flto" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
897 if(NOT LINKER_IS_LLD_LINK)
898 append("-flto" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
902 # This option makes utils/extract_symbols.py be used to determine the list of
903 # symbols to export from LLVM tools. This is necessary when using MSVC if you
904 # want to allow plugins, though note that the plugin has to explicitly link
905 # against (exactly one) tool so we can't unilaterally turn on
906 # LLVM_ENABLE_PLUGINS when it's enabled.
907 option(LLVM_EXPORT_SYMBOLS_FOR_PLUGINS "Export symbols from LLVM tools so that plugins can import them" OFF)
908 if(BUILD_SHARED_LIBS AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
909 message(FATAL_ERROR "BUILD_SHARED_LIBS not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS")
911 if(LLVM_LINK_LLVM_DYLIB AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
912 message(FATAL_ERROR "LLVM_LINK_LLVM_DYLIB not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS")
916 # FIXME: Make this configurable.
918 if(BUILD_SHARED_LIBS OR LLVM_BUILD_LLVM_DYLIB)
919 set(LLVM_ENABLE_PLUGINS ON)
921 set(LLVM_ENABLE_PLUGINS OFF)
924 set(LLVM_ENABLE_PLUGINS ON)
927 # By default we should enable LLVM_ENABLE_IDE only for multi-configuration
928 # generators. This option disables optional build system features that make IDEs
930 set(LLVM_ENABLE_IDE_default OFF)
931 if (CMAKE_CONFIGURATION_TYPES)
932 set(LLVM_ENABLE_IDE_default ON)
934 option(LLVM_ENABLE_IDE
935 "Disable optional build system features that cause problems for IDE generators"
936 ${LLVM_ENABLE_IDE_default})
937 if (CMAKE_CONFIGURATION_TYPES AND NOT LLVM_ENABLE_IDE)
938 message(WARNING "Disabling LLVM_ENABLE_IDE on multi-configuration generators is not recommended.")
941 function(get_compile_definitions)
942 get_directory_property(top_dir_definitions DIRECTORY ${CMAKE_SOURCE_DIR} COMPILE_DEFINITIONS)
943 foreach(definition ${top_dir_definitions})
945 string(APPEND result " -D${definition}")
947 set(result "-D${definition}")
950 set(LLVM_DEFINITIONS "${result}" PARENT_SCOPE)
952 get_compile_definitions()
954 option(LLVM_FORCE_ENABLE_STATS "Enable statistics collection for builds that wouldn't normally enable it" OFF)
956 check_symbol_exists(os_signpost_interval_begin "os/signpost.h" macos_signposts_available)
957 if(macos_signposts_available)
958 check_cxx_source_compiles(
959 "#include <os/signpost.h>
960 int main() { os_signpost_interval_begin(nullptr, 0, \"\", \"\"); return 0; }"
961 macos_signposts_usable)
962 if(macos_signposts_usable)
963 set(LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS "WITH_ASSERTS" CACHE STRING
964 "Enable support for Xcode signposts. Can be WITH_ASSERTS, FORCE_ON, FORCE_OFF")
965 string(TOUPPER "${LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS}"
966 uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS)
967 if( uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS STREQUAL "WITH_ASSERTS" )
968 if( LLVM_ENABLE_ASSERTIONS )
969 set( LLVM_SUPPORT_XCODE_SIGNPOSTS 1 )
971 elseif( uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS STREQUAL "FORCE_ON" )
972 set( LLVM_SUPPORT_XCODE_SIGNPOSTS 1 )
973 elseif( uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS STREQUAL "FORCE_OFF" )
974 # We don't need to do anything special to turn off signposts.
975 elseif( NOT DEFINED LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS )
976 # Treat LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS like "FORCE_OFF" when it has not been
979 message(FATAL_ERROR "Unknown value for LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS:"
980 " \"${LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS}\"!")