1 # This CMake module is responsible for interpreting the user defined LLVM_ 2 # options and executing the appropriate CMake commands to realize the users' 3 # selections. 4 5 # This is commonly needed so make sure it's defined before we include anything 6 # else. 7 string(TOUPPER "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE) 8 9 include(CheckCompilerVersion) 10 include(HandleLLVMStdlib) 11 include(AddLLVMDefinitions) 12 include(CheckCCompilerFlag) 13 include(CheckCXXCompilerFlag) 14 15 16 if (CMAKE_LINKER MATCHES "lld-link.exe") 17 # Pass /MANIFEST:NO so that CMake doesn't run mt.exe on our binaries. Adding 18 # manifests with mt.exe breaks LLD's symbol tables and takes as much time as 19 # the link. See PR24476. 20 append("/MANIFEST:NO" 21 CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS) 22 endif() 23 24 if( LLVM_ENABLE_ASSERTIONS ) 25 # MSVC doesn't like _DEBUG on release builds. See PR 4379. 26 if( NOT MSVC ) 27 add_definitions( -D_DEBUG ) 28 endif() 29 # On non-Debug builds cmake automatically defines NDEBUG, so we 30 # explicitly undefine it: 31 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" ) 32 add_definitions( -UNDEBUG ) 33 # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines. 34 foreach (flags_var_to_scrub 35 CMAKE_CXX_FLAGS_RELEASE 36 CMAKE_CXX_FLAGS_RELWITHDEBINFO 37 CMAKE_CXX_FLAGS_MINSIZEREL 38 CMAKE_C_FLAGS_RELEASE 39 CMAKE_C_FLAGS_RELWITHDEBINFO 40 CMAKE_C_FLAGS_MINSIZEREL) 41 string (REGEX REPLACE "(^| )[/-]D *NDEBUG($| )" " " 42 "${flags_var_to_scrub}" "${${flags_var_to_scrub}}") 43 endforeach() 44 endif() 45 endif() 46 47 if(LLVM_ENABLE_EXPENSIVE_CHECKS) 48 add_definitions(-DEXPENSIVE_CHECKS) 49 add_definitions(-D_GLIBCXX_DEBUG) 50 endif() 51 52 string(TOUPPER "${LLVM_ABI_BREAKING_CHECKS}" uppercase_LLVM_ABI_BREAKING_CHECKS) 53 54 if( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "WITH_ASSERTS" ) 55 if( LLVM_ENABLE_ASSERTIONS ) 56 set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 ) 57 endif() 58 elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_ON" ) 59 set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 ) 60 elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_OFF" ) 61 # We don't need to do anything special to turn off ABI breaking checks. 62 elseif( NOT DEFINED LLVM_ABI_BREAKING_CHECKS ) 63 # Treat LLVM_ABI_BREAKING_CHECKS like "FORCE_OFF" when it has not been 64 # defined. 65 else() 66 message(FATAL_ERROR "Unknown value for LLVM_ABI_BREAKING_CHECKS: \"${LLVM_ABI_BREAKING_CHECKS}\"!") 67 endif() 68 69 if(WIN32) 70 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0) 71 if(CYGWIN) 72 set(LLVM_ON_WIN32 0) 73 set(LLVM_ON_UNIX 1) 74 else(CYGWIN) 75 set(LLVM_ON_WIN32 1) 76 set(LLVM_ON_UNIX 0) 77 endif(CYGWIN) 78 else(WIN32) 79 if(UNIX) 80 set(LLVM_ON_WIN32 0) 81 set(LLVM_ON_UNIX 1) 82 if(APPLE) 83 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0) 84 else(APPLE) 85 set(LLVM_HAVE_LINK_VERSION_SCRIPT 1) 86 endif(APPLE) 87 else(UNIX) 88 MESSAGE(SEND_ERROR "Unable to determine platform") 89 endif(UNIX) 90 endif(WIN32) 91 92 set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX}) 93 set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX}) 94 95 # We use *.dylib rather than *.so on darwin. 96 set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX}) 97 98 if(APPLE) 99 # Darwin-specific linker flags for loadable modules. 100 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-flat_namespace -Wl,-undefined -Wl,suppress") 101 endif() 102 103 # Pass -Wl,-z,defs. This makes sure all symbols are defined. Otherwise a DSO 104 # build might work on ELF but fail on MachO/COFF. 105 if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin" OR WIN32 OR CYGWIN OR 106 ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR 107 ${CMAKE_SYSTEM_NAME} MATCHES "OpenBSD") AND 108 NOT LLVM_USE_SANITIZER) 109 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,defs") 110 endif() 111 112 113 function(append value) 114 foreach(variable ${ARGN}) 115 set(${variable} "${${variable}} ${value}" PARENT_SCOPE) 116 endforeach(variable) 117 endfunction() 118 119 function(append_if condition value) 120 if (${condition}) 121 foreach(variable ${ARGN}) 122 set(${variable} "${${variable}} ${value}" PARENT_SCOPE) 123 endforeach(variable) 124 endif() 125 endfunction() 126 127 macro(add_flag_if_supported flag name) 128 check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}") 129 append_if("C_SUPPORTS_${name}" "${flag}" CMAKE_C_FLAGS) 130 check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}") 131 append_if("CXX_SUPPORTS_${name}" "${flag}" CMAKE_CXX_FLAGS) 132 endmacro() 133 134 function(add_flag_or_print_warning flag name) 135 check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}") 136 check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}") 137 if (C_SUPPORTS_${name} AND CXX_SUPPORTS_${name}) 138 message(STATUS "Building with ${flag}") 139 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE) 140 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE) 141 set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${flag}" PARENT_SCOPE) 142 else() 143 message(WARNING "${flag} is not supported.") 144 endif() 145 endfunction() 146 147 if( LLVM_ENABLE_PIC ) 148 if( XCODE ) 149 # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't 150 # know how to disable this, so just force ENABLE_PIC off for now. 151 message(WARNING "-fPIC not supported with Xcode.") 152 elseif( WIN32 OR CYGWIN) 153 # On Windows all code is PIC. MinGW warns if -fPIC is used. 154 else() 155 add_flag_or_print_warning("-fPIC" FPIC) 156 endif() 157 endif() 158 159 if(NOT WIN32 AND NOT CYGWIN) 160 # MinGW warns if -fvisibility-inlines-hidden is used. 161 check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG) 162 append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS) 163 endif() 164 165 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 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -m32") 170 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -m32") 171 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32") 172 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32") 173 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32") 174 endif( LLVM_BUILD_32_BITS ) 175 endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 ) 176 177 if (LLVM_BUILD_STATIC) 178 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -static") 179 endif() 180 181 if( XCODE ) 182 # For Xcode enable several build settings that correspond to 183 # many warnings that are on by default in Clang but are 184 # not enabled for historical reasons. For versions of Xcode 185 # that do not support these options they will simply 186 # be ignored. 187 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_RETURN_TYPE "YES") 188 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_MISSING_NEWLINE "YES") 189 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VALUE "YES") 190 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VARIABLE "YES") 191 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_SIGN_COMPARE "YES") 192 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_FUNCTION "YES") 193 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_INITIALIZER_NOT_FULLY_BRACKETED "YES") 194 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_HIDDEN_VIRTUAL_FUNCTIONS "YES") 195 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNINITIALIZED_AUTOS "YES") 196 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_BOOL_CONVERSION "YES") 197 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_EMPTY_BODY "YES") 198 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_ENUM_CONVERSION "YES") 199 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_INT_CONVERSION "YES") 200 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_CONSTANT_CONVERSION "YES") 201 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_NON_VIRTUAL_DESTRUCTOR "YES") 202 endif() 203 204 # On Win32 using MS tools, provide an option to set the number of parallel jobs 205 # to use. 206 if( MSVC_IDE ) 207 set(LLVM_COMPILER_JOBS "0" CACHE STRING 208 "Number of parallel compiler jobs. 0 means use all processors. Default is 0.") 209 if( NOT LLVM_COMPILER_JOBS STREQUAL "1" ) 210 if( LLVM_COMPILER_JOBS STREQUAL "0" ) 211 add_llvm_definitions( /MP ) 212 else() 213 message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS}) 214 add_llvm_definitions( /MP${LLVM_COMPILER_JOBS} ) 215 endif() 216 else() 217 message(STATUS "Parallel compilation disabled") 218 endif() 219 endif() 220 221 if( MSVC ) 222 if( CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.0 ) 223 # For MSVC 2013, disable iterator null pointer checking in debug mode, 224 # especially so std::equal(nullptr, nullptr, nullptr) will not assert. 225 add_llvm_definitions("-D_DEBUG_POINTER_IMPL=") 226 endif() 227 228 include(ChooseMSVCCRT) 229 230 # set stack reserved size to ~10MB 231 # CMake previously automatically set this value for MSVC builds, but the 232 # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default 233 # value (1 MB) which is not enough for us in tasks such as parsing recursive 234 # C++ templates in Clang. 235 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /STACK:10000000") 236 237 if( MSVC11 ) 238 add_llvm_definitions(-D_VARIADIC_MAX=10) 239 endif() 240 241 # Add definitions that make MSVC much less annoying. 242 add_llvm_definitions( 243 # For some reason MS wants to deprecate a bunch of standard functions... 244 -D_CRT_SECURE_NO_DEPRECATE 245 -D_CRT_SECURE_NO_WARNINGS 246 -D_CRT_NONSTDC_NO_DEPRECATE 247 -D_CRT_NONSTDC_NO_WARNINGS 248 -D_SCL_SECURE_NO_DEPRECATE 249 -D_SCL_SECURE_NO_WARNINGS 250 ) 251 252 # Tell MSVC to use the Unicode version of the Win32 APIs instead of ANSI. 253 add_llvm_definitions( 254 -DUNICODE 255 -D_UNICODE 256 ) 257 258 set(msvc_warning_flags 259 # Disabled warnings. 260 -wd4141 # Suppress ''modifier' : used more than once' (because of __forceinline combined with inline) 261 -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned' 262 -wd4180 # Suppress 'qualifier applied to function type has no meaning; ignored' 263 -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data' 264 -wd4258 # Suppress ''var' : definition from the for loop is ignored; the definition from the enclosing scope is used' 265 -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data' 266 -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception' 267 -wd4345 # Suppress 'behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized' 268 -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized' 269 -wd4355 # Suppress ''this' : used in base member initializer list' 270 -wd4456 # Suppress 'declaration of 'var' hides local variable' 271 -wd4457 # Suppress 'declaration of 'var' hides function parameter' 272 -wd4458 # Suppress 'declaration of 'var' hides class member' 273 -wd4459 # Suppress 'declaration of 'var' hides global declaration' 274 -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated' 275 -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible' 276 -wd4722 # Suppress 'function' : destructor never returns, potential memory leak 277 -wd4800 # Suppress ''type' : forcing value to bool 'true' or 'false' (performance warning)' 278 -wd4100 # Suppress 'unreferenced formal parameter' 279 -wd4127 # Suppress 'conditional expression is constant' 280 -wd4512 # Suppress 'assignment operator could not be generated' 281 -wd4505 # Suppress 'unreferenced local function has been removed' 282 -wd4610 # Suppress '<class> can never be instantiated' 283 -wd4510 # Suppress 'default constructor could not be generated' 284 -wd4702 # Suppress 'unreachable code' 285 -wd4245 # Suppress 'signed/unsigned mismatch' 286 -wd4706 # Suppress 'assignment within conditional expression' 287 -wd4310 # Suppress 'cast truncates constant value' 288 -wd4701 # Suppress 'potentially uninitialized local variable' 289 -wd4703 # Suppress 'potentially uninitialized local pointer variable' 290 -wd4389 # Suppress 'signed/unsigned mismatch' 291 -wd4611 # Suppress 'interaction between '_setjmp' and C++ object destruction is non-portable' 292 -wd4805 # Suppress 'unsafe mix of type <type> and type <type> in operation' 293 -wd4204 # Suppress 'nonstandard extension used : non-constant aggregate initializer' 294 -wd4577 # Suppress 'noexcept used with no exception handling mode specified; termination on exception is not guaranteed' 295 -wd4091 # Suppress 'typedef: ignored on left of '' when no variable is declared' 296 # C4592 is disabled because of false positives in Visual Studio 2015 297 # Update 1. Re-evaluate the usefulness of this diagnostic with Update 2. 298 -wd4592 # Suppress ''var': symbol will be dynamically initialized (implementation limitation) 299 -wd4319 # Suppress ''operator' : zero extending 'type' to 'type' of greater size' 300 301 # Ideally, we'd like this warning to be enabled, but MSVC 2013 doesn't 302 # support the 'aligned' attribute in the way that clang sources requires (for 303 # any code that uses the LLVM_ALIGNAS macro), so this is must be disabled to 304 # avoid unwanted alignment warnings. 305 # When we switch to requiring a version of MSVC that supports the 'alignas' 306 # specifier (MSVC 2015?) this warning can be re-enabled. 307 -wd4324 # Suppress 'structure was padded due to __declspec(align())' 308 309 # Promoted warnings. 310 -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning. 311 312 # Promoted warnings to errors. 313 -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error. 314 ) 315 316 # Enable warnings 317 if (LLVM_ENABLE_WARNINGS) 318 # Put /W4 in front of all the -we flags. cl.exe doesn't care, but for 319 # clang-cl having /W4 after the -we flags will re-enable the warnings 320 # disabled by -we. 321 set(msvc_warning_flags "/W4 ${msvc_warning_flags}") 322 # CMake appends /W3 by default, and having /W3 followed by /W4 will result in 323 # cl : Command line warning D9025 : overriding '/W3' with '/W4'. Since this is 324 # a command line warning and not a compiler warning, it cannot be suppressed except 325 # by fixing the command line. 326 string(REGEX REPLACE " /W[0-4]" "" CMAKE_C_FLAGS "${CMAKE_C_FLAGS}") 327 string(REGEX REPLACE " /W[0-4]" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}") 328 329 if (LLVM_ENABLE_PEDANTIC) 330 # No MSVC equivalent available 331 endif (LLVM_ENABLE_PEDANTIC) 332 endif (LLVM_ENABLE_WARNINGS) 333 if (LLVM_ENABLE_WERROR) 334 append("/WX" msvc_warning_flags) 335 endif (LLVM_ENABLE_WERROR) 336 337 foreach(flag ${msvc_warning_flags}) 338 append("${flag}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 339 endforeach(flag) 340 341 append("/Zc:inline" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 342 343 # /Zc:strictStrings is incompatible with VS12's (Visual Studio 2013's) 344 # debug mode headers. Instead of only enabling them in VS2013's debug mode, 345 # we'll just enable them for Visual Studio 2015 (VS 14, MSVC_VERSION 1900) 346 # and up. 347 if (NOT (MSVC_VERSION LESS 1900)) 348 # Disable string literal const->non-const type conversion. 349 # "When specified, the compiler requires strict const-qualification 350 # conformance for pointers initialized by using string literals." 351 append("/Zc:strictStrings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 352 endif(NOT (MSVC_VERSION LESS 1900)) 353 354 # "Generate Intrinsic Functions". 355 append("/Oi" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 356 357 # "Enforce type conversion rules". 358 append("/Zc:rvalueCast" CMAKE_CXX_FLAGS) 359 360 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang") 361 # clang-cl and cl by default produce non-deterministic binaries because 362 # link.exe /incremental requires a timestamp in the .obj file. clang-cl 363 # has the flag /Brepro to force deterministic binaries. We want to pass that 364 # whenever you're building with clang unless you're passing /incremental. 365 # This checks CMAKE_CXX_COMPILER_ID in addition to check_cxx_compiler_flag() 366 # because cl.exe does not emit an error on flags it doesn't understand, 367 # letting check_cxx_compiler_flag() claim it understands all flags. 368 check_cxx_compiler_flag("/Brepro" SUPPORTS_BREPRO) 369 if (SUPPORTS_BREPRO) 370 # Check if /INCREMENTAL is passed to the linker and complain that it 371 # won't work with /Brepro. 372 string(TOUPPER "${CMAKE_EXE_LINKER_FLAGS}" upper_exe_flags) 373 string(TOUPPER "${CMAKE_MODULE_LINKER_FLAGS}" upper_module_flags) 374 string(TOUPPER "${CMAKE_SHARED_LINKER_FLAGS}" upper_shared_flags) 375 376 string(FIND "${upper_exe_flags} ${upper_module_flags} ${upper_shared_flags}" 377 "/INCREMENTAL" linker_flag_idx) 378 379 if (${linker_flag_idx} GREATER -1) 380 message(WARNING "/Brepro not compatible with /INCREMENTAL linking - builds will be non-deterministic") 381 else() 382 append("/Brepro" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 383 endif() 384 endif() 385 endif() 386 387 # Disable sized deallocation if the flag is supported. MSVC fails to compile 388 # the operator new overload in User otherwise. 389 check_c_compiler_flag("/WX /Zc:sizedDealloc-" SUPPORTS_SIZED_DEALLOC) 390 append_if(SUPPORTS_SIZED_DEALLOC "/Zc:sizedDealloc-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 391 392 elseif( LLVM_COMPILER_IS_GCC_COMPATIBLE ) 393 if (LLVM_ENABLE_WARNINGS) 394 append("-Wall -W -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 395 append("-Wcast-qual" CMAKE_CXX_FLAGS) 396 397 # Turn off missing field initializer warnings for gcc to avoid noise from 398 # false positives with empty {}. Turn them on otherwise (they're off by 399 # default for clang). 400 check_cxx_compiler_flag("-Wmissing-field-initializers" CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG) 401 if (CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG) 402 if (CMAKE_COMPILER_IS_GNUCXX) 403 append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 404 else() 405 append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 406 endif() 407 endif() 408 409 append_if(LLVM_ENABLE_PEDANTIC "-pedantic" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 410 append_if(LLVM_ENABLE_PEDANTIC "-Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 411 add_flag_if_supported("-Wcovered-switch-default" COVERED_SWITCH_DEFAULT_FLAG) 412 append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS) 413 append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS) 414 415 # Check if -Wnon-virtual-dtor warns even though the class is marked final. 416 # If it does, don't add it. So it won't be added on clang 3.4 and older. 417 # This also catches cases when -Wnon-virtual-dtor isn't supported by 418 # the compiler at all. This flag is not activated for gcc since it will 419 # incorrectly identify a protected non-virtual base when there is a friend 420 # declaration. 421 if (NOT CMAKE_COMPILER_IS_GNUCXX) 422 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 423 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++11 -Werror=non-virtual-dtor") 424 CHECK_CXX_SOURCE_COMPILES("class base {public: virtual void anchor();protected: ~base();}; 425 class derived final : public base { public: ~derived();}; 426 int main() { return 0; }" 427 CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR) 428 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 429 append_if(CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR 430 "-Wnon-virtual-dtor" CMAKE_CXX_FLAGS) 431 endif() 432 433 # Enable -Wdelete-non-virtual-dtor if available. 434 add_flag_if_supported("-Wdelete-non-virtual-dtor" DELETE_NON_VIRTUAL_DTOR_FLAG) 435 436 # Check if -Wcomment is OK with an // comment ending with '\' if the next 437 # line is also a // comment. 438 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 439 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror -Wcomment") 440 CHECK_C_SOURCE_COMPILES("// \\\\\\n//\\nint main() {return 0;}" 441 C_WCOMMENT_ALLOWS_LINE_WRAP) 442 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 443 if (NOT C_WCOMMENT_ALLOWS_LINE_WRAP) 444 append("-Wno-comment" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 445 endif() 446 endif (LLVM_ENABLE_WARNINGS) 447 append_if(LLVM_ENABLE_WERROR "-Werror" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 448 add_flag_if_supported("-Werror=date-time" WERROR_DATE_TIME) 449 if (LLVM_ENABLE_CXX1Y) 450 check_cxx_compiler_flag("-std=c++1y" CXX_SUPPORTS_CXX1Y) 451 append_if(CXX_SUPPORTS_CXX1Y "-std=c++1y" CMAKE_CXX_FLAGS) 452 else() 453 check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11) 454 if (CXX_SUPPORTS_CXX11) 455 if (CYGWIN OR MINGW) 456 # MinGW and Cygwin are a bit stricter and lack things like 457 # 'strdup', 'stricmp', etc in c++11 mode. 458 append("-std=gnu++11" CMAKE_CXX_FLAGS) 459 else() 460 append("-std=c++11" CMAKE_CXX_FLAGS) 461 endif() 462 else() 463 message(FATAL_ERROR "LLVM requires C++11 support but the '-std=c++11' flag isn't supported.") 464 endif() 465 endif() 466 if (LLVM_ENABLE_MODULES) 467 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 468 set(module_flags "-fmodules -fmodules-cache-path=module.cache") 469 if (${CMAKE_SYSTEM_NAME} MATCHES "Darwin") 470 # On Darwin -fmodules does not imply -fcxx-modules. 471 set(module_flags "${module_flags} -fcxx-modules") 472 endif() 473 if (LLVM_ENABLE_LOCAL_SUBMODULE_VISIBILITY) 474 set(module_flags "${module_flags} -Xclang -fmodules-local-submodule-visibility") 475 endif() 476 if (LLVM_ENABLE_MODULE_DEBUGGING AND 477 ((uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") OR 478 (uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO"))) 479 set(module_flags "${module_flags} -gmodules") 480 endif() 481 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${module_flags}") 482 483 # Check that we can build code with modules enabled, and that repeatedly 484 # including <cassert> still manages to respect NDEBUG properly. 485 CHECK_CXX_SOURCE_COMPILES("#undef NDEBUG 486 #include <cassert> 487 #define NDEBUG 488 #include <cassert> 489 int main() { assert(this code is not compiled); }" 490 CXX_SUPPORTS_MODULES) 491 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 492 if (CXX_SUPPORTS_MODULES) 493 append("${module_flags}" CMAKE_CXX_FLAGS) 494 else() 495 message(FATAL_ERROR "LLVM_ENABLE_MODULES is not supported by this compiler") 496 endif() 497 endif(LLVM_ENABLE_MODULES) 498 endif( MSVC ) 499 500 macro(append_common_sanitizer_flags) 501 if (NOT MSVC) 502 # Append -fno-omit-frame-pointer and turn on debug info to get better 503 # stack traces. 504 add_flag_if_supported("-fno-omit-frame-pointer" FNO_OMIT_FRAME_POINTER) 505 if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND 506 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO") 507 add_flag_if_supported("-gline-tables-only" GLINE_TABLES_ONLY) 508 endif() 509 # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large. 510 if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") 511 add_flag_if_supported("-O1" O1) 512 endif() 513 elseif (CLANG_CL) 514 # Keep frame pointers around. 515 append("/Oy-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 516 if (CMAKE_LINKER MATCHES "lld-link.exe") 517 # Use DWARF debug info with LLD. 518 append("-gdwarf" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 519 else() 520 # Enable codeview otherwise. 521 append("/Z7" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 522 endif() 523 # Always ask the linker to produce symbols with asan. 524 append("-debug" CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS) 525 endif() 526 endmacro() 527 528 # Turn on sanitizers if necessary. 529 if(LLVM_USE_SANITIZER) 530 if (LLVM_ON_UNIX) 531 if (LLVM_USE_SANITIZER STREQUAL "Address") 532 append_common_sanitizer_flags() 533 append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 534 elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?") 535 append_common_sanitizer_flags() 536 append("-fsanitize=memory" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 537 if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins") 538 append("-fsanitize-memory-track-origins" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 539 endif() 540 elseif (LLVM_USE_SANITIZER STREQUAL "Undefined") 541 append_common_sanitizer_flags() 542 append("-fsanitize=undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all" 543 CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 544 elseif (LLVM_USE_SANITIZER STREQUAL "Thread") 545 append_common_sanitizer_flags() 546 append("-fsanitize=thread" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 547 elseif (LLVM_USE_SANITIZER STREQUAL "Address;Undefined" OR 548 LLVM_USE_SANITIZER STREQUAL "Undefined;Address") 549 append_common_sanitizer_flags() 550 append("-fsanitize=address,undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all" 551 CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 552 else() 553 message(FATAL_ERROR "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}") 554 endif() 555 elseif(MSVC) 556 if (LLVM_USE_SANITIZER STREQUAL "Address") 557 append_common_sanitizer_flags() 558 append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 559 else() 560 message(FATAL_ERROR "This sanitizer not yet supported in the MSVC environment: ${LLVM_USE_SANITIZER}") 561 endif() 562 else() 563 message(FATAL_ERROR "LLVM_USE_SANITIZER is not supported on this platform.") 564 endif() 565 if (LLVM_USE_SANITIZE_COVERAGE) 566 append("-fsanitize-coverage=edge,indirect-calls,8bit-counters,trace-cmp" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 567 endif() 568 endif() 569 570 # Turn on -gsplit-dwarf if requested 571 if(LLVM_USE_SPLIT_DWARF) 572 add_definitions("-gsplit-dwarf") 573 endif() 574 575 add_llvm_definitions( -D__STDC_CONSTANT_MACROS ) 576 add_llvm_definitions( -D__STDC_FORMAT_MACROS ) 577 add_llvm_definitions( -D__STDC_LIMIT_MACROS ) 578 579 # clang doesn't print colored diagnostics when invoked from Ninja 580 if (UNIX AND 581 CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND 582 CMAKE_GENERATOR STREQUAL "Ninja") 583 append("-fcolor-diagnostics" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 584 endif() 585 586 # Add flags for add_dead_strip(). 587 # FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF? 588 # But MinSizeRel seems to add that automatically, so maybe disable these 589 # flags instead if LLVM_NO_DEAD_STRIP is set. 590 if(NOT CYGWIN AND NOT WIN32) 591 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin" AND 592 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") 593 check_c_compiler_flag("-Werror -fno-function-sections" C_SUPPORTS_FNO_FUNCTION_SECTIONS) 594 if (C_SUPPORTS_FNO_FUNCTION_SECTIONS) 595 # Don't add -ffunction-section if it can be disabled with -fno-function-sections. 596 # Doing so will break sanitizers. 597 add_flag_if_supported("-ffunction-sections" FFUNCTION_SECTIONS) 598 endif() 599 add_flag_if_supported("-fdata-sections" FDATA_SECTIONS) 600 endif() 601 endif() 602 603 if(MSVC) 604 # Remove flags here, for exceptions and RTTI. 605 # Each target property or source property should be responsible to control 606 # them. 607 # CL.EXE complains to override flags like "/GR /GR-". 608 string(REGEX REPLACE "(^| ) */EH[-cs]+ *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}") 609 string(REGEX REPLACE "(^| ) */GR-? *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}") 610 endif() 611 612 # Provide public options to globally control RTTI and EH 613 option(LLVM_ENABLE_EH "Enable Exception handling" OFF) 614 option(LLVM_ENABLE_RTTI "Enable run time type information" OFF) 615 if(LLVM_ENABLE_EH AND NOT LLVM_ENABLE_RTTI) 616 message(FATAL_ERROR "Exception handling requires RTTI. You must set LLVM_ENABLE_RTTI to ON") 617 endif() 618 619 option(LLVM_BUILD_INSTRUMENTED "Build LLVM and tools with PGO instrumentation (experimental)" Off) 620 mark_as_advanced(LLVM_BUILD_INSTRUMENTED) 621 append_if(LLVM_BUILD_INSTRUMENTED "-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}'" 622 CMAKE_CXX_FLAGS 623 CMAKE_C_FLAGS 624 CMAKE_EXE_LINKER_FLAGS 625 CMAKE_SHARED_LINKER_FLAGS) 626 627 option(LLVM_BUILD_INSTRUMENTED_COVERAGE "Build LLVM and tools with Code Coverage instrumentation (experimental)" Off) 628 mark_as_advanced(LLVM_BUILD_INSTRUMENTED_COVERAGE) 629 append_if(LLVM_BUILD_INSTRUMENTED_COVERAGE "-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}' -fcoverage-mapping" 630 CMAKE_CXX_FLAGS 631 CMAKE_C_FLAGS 632 CMAKE_EXE_LINKER_FLAGS 633 CMAKE_SHARED_LINKER_FLAGS) 634 635 set(LLVM_ENABLE_LTO OFF CACHE STRING "Build LLVM with LTO. May be specified as Thin or Full to use a particular kind of LTO") 636 string(TOUPPER "${LLVM_ENABLE_LTO}" uppercase_LLVM_ENABLE_LTO) 637 if(uppercase_LLVM_ENABLE_LTO STREQUAL "THIN") 638 append("-flto=thin" CMAKE_CXX_FLAGS CMAKE_C_FLAGS 639 CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS) 640 elseif(uppercase_LLVM_ENABLE_LTO STREQUAL "FULL") 641 append("-flto=full" CMAKE_CXX_FLAGS CMAKE_C_FLAGS 642 CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS) 643 elseif(LLVM_ENABLE_LTO) 644 append("-flto" CMAKE_CXX_FLAGS CMAKE_C_FLAGS 645 CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS) 646 endif() 647 648 # This option makes utils/extract_symbols.py be used to determine the list of 649 # symbols to export from LLVM tools. This is necessary when using MSVC if you 650 # want to allow plugins, though note that the plugin has to explicitly link 651 # against (exactly one) tool so we can't unilaterally turn on 652 # LLVM_ENABLE_PLUGINS when it's enabled. 653 option(LLVM_EXPORT_SYMBOLS_FOR_PLUGINS "Export symbols from LLVM tools so that plugins can import them" OFF) 654 if(BUILD_SHARED_LIBS AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS) 655 message(FATAL_ERROR "BUILD_SHARED_LIBS not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS") 656 endif() 657 if(LLVM_LINK_LLVM_DYLIB AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS) 658 message(FATAL_ERROR "LLVM_LINK_LLVM_DYLIB not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS") 659 endif() 660 661 # Plugin support 662 # FIXME: Make this configurable. 663 if(WIN32 OR CYGWIN) 664 if(BUILD_SHARED_LIBS) 665 set(LLVM_ENABLE_PLUGINS ON) 666 else() 667 set(LLVM_ENABLE_PLUGINS OFF) 668 endif() 669 else() 670 set(LLVM_ENABLE_PLUGINS ON) 671 endif() 672
