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. 7string(TOUPPER "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE) 8 9include(HandleLLVMStdlib) 10include(AddLLVMDefinitions) 11include(CheckCCompilerFlag) 12include(CheckCXXCompilerFlag) 13 14if(NOT LLVM_FORCE_USE_OLD_TOOLCHAIN) 15 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU") 16 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.7) 17 message(FATAL_ERROR "Host GCC version must be at least 4.7!") 18 endif() 19 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang") 20 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.1) 21 message(FATAL_ERROR "Host Clang version must be at least 3.1!") 22 endif() 23 24 if (CMAKE_CXX_SIMULATE_ID MATCHES "MSVC") 25 if (CMAKE_CXX_SIMULATE_VERSION VERSION_LESS 18.0) 26 message(FATAL_ERROR "Host Clang must have at least -fms-compatibility-version=18.0") 27 endif() 28 set(CLANG_CL 1) 29 elseif(NOT LLVM_ENABLE_LIBCXX) 30 # Otherwise, test that we aren't using too old of a version of libstdc++ 31 # with the Clang compiler. This is tricky as there is no real way to 32 # check the version of libstdc++ directly. Instead we test for a known 33 # bug in libstdc++4.6 that is fixed in libstdc++4.7. 34 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 35 set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES}) 36 set(CMAKE_REQUIRED_FLAGS "-std=c++0x") 37 check_cxx_source_compiles(" 38#include <atomic> 39std::atomic<float> x(0.0f); 40int main() { return (float)x; }" 41 LLVM_NO_OLD_LIBSTDCXX) 42 if(NOT LLVM_NO_OLD_LIBSTDCXX) 43 message(FATAL_ERROR "Host Clang must be able to find libstdc++4.7 or newer!") 44 endif() 45 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 46 set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES}) 47 endif() 48 elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC") 49 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 18.0) 50 message(FATAL_ERROR "Host Visual Studio must be at least 2013") 51 elseif(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 18.0.31101) 52 message(WARNING "Host Visual Studio should at least be 2013 Update 4 (MSVC 18.0.31101)" 53 " due to miscompiles from earlier versions") 54 endif() 55 endif() 56endif() 57 58if( LLVM_ENABLE_ASSERTIONS ) 59 # MSVC doesn't like _DEBUG on release builds. See PR 4379. 60 if( NOT MSVC ) 61 add_definitions( -D_DEBUG ) 62 endif() 63 # On non-Debug builds cmake automatically defines NDEBUG, so we 64 # explicitly undefine it: 65 if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" ) 66 add_definitions( -UNDEBUG ) 67 # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines. 68 foreach (flags_var_to_scrub 69 CMAKE_CXX_FLAGS_RELEASE 70 CMAKE_CXX_FLAGS_RELWITHDEBINFO 71 CMAKE_CXX_FLAGS_MINSIZEREL 72 CMAKE_C_FLAGS_RELEASE 73 CMAKE_C_FLAGS_RELWITHDEBINFO 74 CMAKE_C_FLAGS_MINSIZEREL) 75 string (REGEX REPLACE "(^| )[/-]D *NDEBUG($| )" " " 76 "${flags_var_to_scrub}" "${${flags_var_to_scrub}}") 77 endforeach() 78 endif() 79endif() 80 81string(TOUPPER "${LLVM_ABI_BREAKING_CHECKS}" uppercase_LLVM_ABI_BREAKING_CHECKS) 82 83if( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "WITH_ASSERTS" ) 84 if( LLVM_ENABLE_ASSERTIONS ) 85 set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 ) 86 endif() 87elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_ON" ) 88 set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 ) 89elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_OFF" ) 90 # We don't need to do anything special to turn off ABI breaking checks. 91elseif( NOT DEFINED LLVM_ABI_BREAKING_CHECKS ) 92 # Treat LLVM_ABI_BREAKING_CHECKS like "FORCE_OFF" when it has not been 93 # defined. 94else() 95 message(FATAL_ERROR "Unknown value for LLVM_ABI_BREAKING_CHECKS: \"${LLVM_ABI_BREAKING_CHECKS}\"!") 96endif() 97 98if(WIN32) 99 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0) 100 if(CYGWIN) 101 set(LLVM_ON_WIN32 0) 102 set(LLVM_ON_UNIX 1) 103 else(CYGWIN) 104 set(LLVM_ON_WIN32 1) 105 set(LLVM_ON_UNIX 0) 106 endif(CYGWIN) 107else(WIN32) 108 if(UNIX) 109 set(LLVM_ON_WIN32 0) 110 set(LLVM_ON_UNIX 1) 111 if(APPLE) 112 set(LLVM_HAVE_LINK_VERSION_SCRIPT 0) 113 else(APPLE) 114 set(LLVM_HAVE_LINK_VERSION_SCRIPT 1) 115 endif(APPLE) 116 else(UNIX) 117 MESSAGE(SEND_ERROR "Unable to determine platform") 118 endif(UNIX) 119endif(WIN32) 120 121set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX}) 122set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX}) 123 124# We use *.dylib rather than *.so on darwin. 125set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX}) 126 127if(APPLE) 128 # Darwin-specific linker flags for loadable modules. 129 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-flat_namespace -Wl,-undefined -Wl,suppress") 130endif() 131 132# Pass -Wl,-z,defs. This makes sure all symbols are defined. Otherwise a DSO 133# build might work on ELF but fail on MachO/COFF. 134if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin" OR WIN32 OR CYGWIN OR 135 ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR 136 ${CMAKE_SYSTEM_NAME} MATCHES "OpenBSD") AND 137 NOT LLVM_USE_SANITIZER) 138 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,defs") 139endif() 140 141 142function(append value) 143 foreach(variable ${ARGN}) 144 set(${variable} "${${variable}} ${value}" PARENT_SCOPE) 145 endforeach(variable) 146endfunction() 147 148function(append_if condition value) 149 if (${condition}) 150 foreach(variable ${ARGN}) 151 set(${variable} "${${variable}} ${value}" PARENT_SCOPE) 152 endforeach(variable) 153 endif() 154endfunction() 155 156macro(add_flag_if_supported flag name) 157 check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}") 158 append_if("C_SUPPORTS_${name}" "${flag}" CMAKE_C_FLAGS) 159 check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}") 160 append_if("CXX_SUPPORTS_${name}" "${flag}" CMAKE_CXX_FLAGS) 161endmacro() 162 163function(add_flag_or_print_warning flag name) 164 check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}") 165 check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}") 166 if (C_SUPPORTS_${name} AND CXX_SUPPORTS_${name}) 167 message(STATUS "Building with ${flag}") 168 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE) 169 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE) 170 set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${flag}" PARENT_SCOPE) 171 else() 172 message(WARNING "${flag} is not supported.") 173 endif() 174endfunction() 175 176if( LLVM_ENABLE_PIC ) 177 if( XCODE ) 178 # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't 179 # know how to disable this, so just force ENABLE_PIC off for now. 180 message(WARNING "-fPIC not supported with Xcode.") 181 elseif( WIN32 OR CYGWIN) 182 # On Windows all code is PIC. MinGW warns if -fPIC is used. 183 else() 184 add_flag_or_print_warning("-fPIC" FPIC) 185 endif() 186endif() 187 188if(NOT WIN32 AND NOT CYGWIN) 189 # MinGW warns if -fvisibility-inlines-hidden is used. 190 check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG) 191 append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS) 192endif() 193 194if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 ) 195 # TODO: support other platforms and toolchains. 196 if( LLVM_BUILD_32_BITS ) 197 message(STATUS "Building 32 bits executables and libraries.") 198 add_llvm_definitions( -m32 ) 199 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32") 200 set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32") 201 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32") 202 endif( LLVM_BUILD_32_BITS ) 203endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 ) 204 205if (LLVM_BUILD_STATIC) 206 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -static") 207endif() 208 209if( XCODE ) 210 # For Xcode enable several build settings that correspond to 211 # many warnings that are on by default in Clang but are 212 # not enabled for historical reasons. For versions of Xcode 213 # that do not support these options they will simply 214 # be ignored. 215 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_RETURN_TYPE "YES") 216 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_MISSING_NEWLINE "YES") 217 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VALUE "YES") 218 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VARIABLE "YES") 219 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_SIGN_COMPARE "YES") 220 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_FUNCTION "YES") 221 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_INITIALIZER_NOT_FULLY_BRACKETED "YES") 222 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_HIDDEN_VIRTUAL_FUNCTIONS "YES") 223 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNINITIALIZED_AUTOS "YES") 224 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_BOOL_CONVERSION "YES") 225 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_EMPTY_BODY "YES") 226 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_ENUM_CONVERSION "YES") 227 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_INT_CONVERSION "YES") 228 set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_CONSTANT_CONVERSION "YES") 229 set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_NON_VIRTUAL_DESTRUCTOR "YES") 230endif() 231 232# On Win32 using MS tools, provide an option to set the number of parallel jobs 233# to use. 234if( MSVC_IDE ) 235 set(LLVM_COMPILER_JOBS "0" CACHE STRING 236 "Number of parallel compiler jobs. 0 means use all processors. Default is 0.") 237 if( NOT LLVM_COMPILER_JOBS STREQUAL "1" ) 238 if( LLVM_COMPILER_JOBS STREQUAL "0" ) 239 add_llvm_definitions( /MP ) 240 else() 241 message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS}) 242 add_llvm_definitions( /MP${LLVM_COMPILER_JOBS} ) 243 endif() 244 else() 245 message(STATUS "Parallel compilation disabled") 246 endif() 247endif() 248 249if( MSVC ) 250 if( CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.0 ) 251 # For MSVC 2013, disable iterator null pointer checking in debug mode, 252 # especially so std::equal(nullptr, nullptr, nullptr) will not assert. 253 add_llvm_definitions("-D_DEBUG_POINTER_IMPL=") 254 endif() 255 256 include(ChooseMSVCCRT) 257 258 if( NOT (${CMAKE_VERSION} VERSION_LESS 2.8.11) ) 259 # set stack reserved size to ~10MB 260 # CMake previously automatically set this value for MSVC builds, but the 261 # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default 262 # value (1 MB) which is not enough for us in tasks such as parsing recursive 263 # C++ templates in Clang. 264 set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /STACK:10000000") 265 endif() 266 267 if( MSVC11 ) 268 add_llvm_definitions(-D_VARIADIC_MAX=10) 269 endif() 270 271 # Add definitions that make MSVC much less annoying. 272 add_llvm_definitions( 273 # For some reason MS wants to deprecate a bunch of standard functions... 274 -D_CRT_SECURE_NO_DEPRECATE 275 -D_CRT_SECURE_NO_WARNINGS 276 -D_CRT_NONSTDC_NO_DEPRECATE 277 -D_CRT_NONSTDC_NO_WARNINGS 278 -D_SCL_SECURE_NO_DEPRECATE 279 -D_SCL_SECURE_NO_WARNINGS 280 ) 281 282 set(msvc_warning_flags 283 # Disabled warnings. 284 -wd4141 # Suppress ''modifier' : used more than once' (because of __forceinline combined with inline) 285 -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned' 286 -wd4180 # Suppress 'qualifier applied to function type has no meaning; ignored' 287 -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data' 288 -wd4258 # Suppress ''var' : definition from the for loop is ignored; the definition from the enclosing scope is used' 289 -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data' 290 -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception' 291 -wd4345 # Suppress 'behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized' 292 -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized' 293 -wd4355 # Suppress ''this' : used in base member initializer list' 294 -wd4456 # Suppress 'declaration of 'var' hides local variable' 295 -wd4457 # Suppress 'declaration of 'var' hides function parameter' 296 -wd4458 # Suppress 'declaration of 'var' hides class member' 297 -wd4459 # Suppress 'declaration of 'var' hides global declaration' 298 -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated' 299 -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible' 300 -wd4722 # Suppress 'function' : destructor never returns, potential memory leak 301 -wd4800 # Suppress ''type' : forcing value to bool 'true' or 'false' (performance warning)' 302 -wd4100 # Suppress 'unreferenced formal parameter' 303 -wd4127 # Suppress 'conditional expression is constant' 304 -wd4512 # Suppress 'assignment operator could not be generated' 305 -wd4505 # Suppress 'unreferenced local function has been removed' 306 -wd4610 # Suppress '<class> can never be instantiated' 307 -wd4510 # Suppress 'default constructor could not be generated' 308 -wd4702 # Suppress 'unreachable code' 309 -wd4245 # Suppress 'signed/unsigned mismatch' 310 -wd4706 # Suppress 'assignment within conditional expression' 311 -wd4310 # Suppress 'cast truncates constant value' 312 -wd4701 # Suppress 'potentially uninitialized local variable' 313 -wd4703 # Suppress 'potentially uninitialized local pointer variable' 314 -wd4389 # Suppress 'signed/unsigned mismatch' 315 -wd4611 # Suppress 'interaction between '_setjmp' and C++ object destruction is non-portable' 316 -wd4805 # Suppress 'unsafe mix of type <type> and type <type> in operation' 317 -wd4204 # Suppress 'nonstandard extension used : non-constant aggregate initializer' 318 -wd4577 # Suppress 'noexcept used with no exception handling mode specified; termination on exception is not guaranteed' 319 -wd4091 # Suppress 'typedef: ignored on left of '' when no variable is declared' 320 # C4592 is disabled because of false positives in Visual Studio 2015 321 # Update 1. Re-evaluate the usefulness of this diagnostic with Update 2. 322 -wd4592 # Suppress ''var': symbol will be dynamically initialized (implementation limitation) 323 324 # Ideally, we'd like this warning to be enabled, but MSVC 2013 doesn't 325 # support the 'aligned' attribute in the way that clang sources requires (for 326 # any code that uses the LLVM_ALIGNAS macro), so this is must be disabled to 327 # avoid unwanted alignment warnings. 328 # When we switch to requiring a version of MSVC that supports the 'alignas' 329 # specifier (MSVC 2015?) this warning can be re-enabled. 330 -wd4324 # Suppress 'structure was padded due to __declspec(align())' 331 332 # Promoted warnings. 333 -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning. 334 335 # Promoted warnings to errors. 336 -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error. 337 ) 338 339 # Enable warnings 340 if (LLVM_ENABLE_WARNINGS) 341 append("/W4" msvc_warning_flags) 342 # CMake appends /W3 by default, and having /W3 followed by /W4 will result in 343 # cl : Command line warning D9025 : overriding '/W3' with '/W4'. Since this is 344 # a command line warning and not a compiler warning, it cannot be suppressed except 345 # by fixing the command line. 346 string(REGEX REPLACE " /W[0-4]" "" CMAKE_C_FLAGS "${CMAKE_C_FLAGS}") 347 string(REGEX REPLACE " /W[0-4]" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}") 348 349 if (LLVM_ENABLE_PEDANTIC) 350 # No MSVC equivalent available 351 endif (LLVM_ENABLE_PEDANTIC) 352 endif (LLVM_ENABLE_WARNINGS) 353 if (LLVM_ENABLE_WERROR) 354 append("/WX" msvc_warning_flags) 355 endif (LLVM_ENABLE_WERROR) 356 357 foreach(flag ${msvc_warning_flags}) 358 append("${flag}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 359 endforeach(flag) 360 361 append("/Zc:inline" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 362 363 # Disable sized deallocation if the flag is supported. MSVC fails to compile 364 # the operator new overload in User otherwise. 365 check_c_compiler_flag("/WX /Zc:sizedDealloc-" SUPPORTS_SIZED_DEALLOC) 366 append_if(SUPPORTS_SIZED_DEALLOC "/Zc:sizedDealloc-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 367 368elseif( LLVM_COMPILER_IS_GCC_COMPATIBLE ) 369 if (LLVM_ENABLE_WARNINGS) 370 append("-Wall -W -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 371 append("-Wcast-qual" CMAKE_CXX_FLAGS) 372 373 # Turn off missing field initializer warnings for gcc to avoid noise from 374 # false positives with empty {}. Turn them on otherwise (they're off by 375 # default for clang). 376 check_cxx_compiler_flag("-Wmissing-field-initializers" CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG) 377 if (CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG) 378 if (CMAKE_COMPILER_IS_GNUCXX) 379 append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 380 else() 381 append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 382 endif() 383 endif() 384 385 append_if(LLVM_ENABLE_PEDANTIC "-pedantic" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 386 append_if(LLVM_ENABLE_PEDANTIC "-Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 387 add_flag_if_supported("-Wcovered-switch-default" COVERED_SWITCH_DEFAULT_FLAG) 388 append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS) 389 append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS) 390 391 # Check if -Wnon-virtual-dtor warns even though the class is marked final. 392 # If it does, don't add it. So it won't be added on clang 3.4 and older. 393 # This also catches cases when -Wnon-virtual-dtor isn't supported by 394 # the compiler at all. This flag is not activated for gcc since it will 395 # incorrectly identify a protected non-virtual base when there is a friend 396 # declaration. 397 if (NOT CMAKE_COMPILER_IS_GNUCXX) 398 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 399 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++11 -Werror=non-virtual-dtor") 400 CHECK_CXX_SOURCE_COMPILES("class base {public: virtual void anchor();protected: ~base();}; 401 class derived final : public base { public: ~derived();}; 402 int main() { return 0; }" 403 CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR) 404 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 405 append_if(CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR 406 "-Wnon-virtual-dtor" CMAKE_CXX_FLAGS) 407 endif() 408 409 # Enable -Wdelete-non-virtual-dtor if available. 410 add_flag_if_supported("-Wdelete-non-virtual-dtor" DELETE_NON_VIRTUAL_DTOR_FLAG) 411 412 # Check if -Wcomment is OK with an // comment ending with '\' if the next 413 # line is also a // comment. 414 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 415 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror -Wcomment") 416 CHECK_C_SOURCE_COMPILES("// \\\\\\n//\\nint main() {return 0;}" 417 C_WCOMMENT_ALLOWS_LINE_WRAP) 418 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 419 if (NOT C_WCOMMENT_ALLOWS_LINE_WRAP) 420 append("-Wno-comment" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 421 endif() 422 endif (LLVM_ENABLE_WARNINGS) 423 append_if(LLVM_ENABLE_WERROR "-Werror" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 424 if (NOT LLVM_ENABLE_TIMESTAMPS) 425 add_flag_if_supported("-Werror=date-time" WERROR_DATE_TIME) 426 endif () 427 if (LLVM_ENABLE_CXX1Y) 428 check_cxx_compiler_flag("-std=c++1y" CXX_SUPPORTS_CXX1Y) 429 append_if(CXX_SUPPORTS_CXX1Y "-std=c++1y" CMAKE_CXX_FLAGS) 430 else() 431 check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11) 432 if (CXX_SUPPORTS_CXX11) 433 if (CYGWIN OR MINGW) 434 # MinGW and Cygwin are a bit stricter and lack things like 435 # 'strdup', 'stricmp', etc in c++11 mode. 436 append("-std=gnu++11" CMAKE_CXX_FLAGS) 437 else() 438 append("-std=c++11" CMAKE_CXX_FLAGS) 439 endif() 440 else() 441 message(FATAL_ERROR "LLVM requires C++11 support but the '-std=c++11' flag isn't supported.") 442 endif() 443 endif() 444 if (LLVM_ENABLE_MODULES) 445 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 446 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -fmodules") 447 # Check that we can build code with modules enabled, and that repeatedly 448 # including <cassert> still manages to respect NDEBUG properly. 449 CHECK_CXX_SOURCE_COMPILES("#undef NDEBUG 450 #include <cassert> 451 #define NDEBUG 452 #include <cassert> 453 int main() { assert(this code is not compiled); }" 454 CXX_SUPPORTS_MODULES) 455 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 456 if (CXX_SUPPORTS_MODULES) 457 append_if(CXX_SUPPORTS_MODULES "-fmodules" CMAKE_C_FLAGS) 458 append_if(CXX_SUPPORTS_MODULES "-fmodules -fcxx-modules" CMAKE_CXX_FLAGS) 459 else() 460 message(FATAL_ERROR "LLVM_ENABLE_MODULES is not supported by this compiler") 461 endif() 462 endif(LLVM_ENABLE_MODULES) 463endif( MSVC ) 464 465macro(append_common_sanitizer_flags) 466 if (NOT MSVC) 467 # Append -fno-omit-frame-pointer and turn on debug info to get better 468 # stack traces. 469 add_flag_if_supported("-fno-omit-frame-pointer" FNO_OMIT_FRAME_POINTER) 470 if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND 471 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO") 472 add_flag_if_supported("-gline-tables-only" GLINE_TABLES_ONLY) 473 endif() 474 # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large. 475 if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") 476 add_flag_if_supported("-O1" O1) 477 endif() 478 elseif (CLANG_CL) 479 # Keep frame pointers around. 480 append("/Oy-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 481 if (CMAKE_LINKER MATCHES "lld-link.exe") 482 # Use DWARF debug info with LLD. 483 append("-gdwarf" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 484 # Pass /MANIFEST:NO so that CMake doesn't run mt.exe on our binaries. 485 # Adding manifests with mt.exe breaks LLD's symbol tables. See PR24476. 486 append("/MANIFEST:NO" 487 CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS) 488 else() 489 # Enable codeview otherwise. 490 append("/Z7" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 491 endif() 492 # Always ask the linker to produce symbols with asan. 493 append("-debug" CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS) 494 endif() 495endmacro() 496 497# Turn on sanitizers if necessary. 498if(LLVM_USE_SANITIZER) 499 if (LLVM_ON_UNIX) 500 if (LLVM_USE_SANITIZER STREQUAL "Address") 501 append_common_sanitizer_flags() 502 append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 503 elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?") 504 append_common_sanitizer_flags() 505 append("-fsanitize=memory" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 506 if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins") 507 append("-fsanitize-memory-track-origins" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 508 endif() 509 elseif (LLVM_USE_SANITIZER STREQUAL "Undefined") 510 append_common_sanitizer_flags() 511 append("-fsanitize=undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all" 512 CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 513 elseif (LLVM_USE_SANITIZER STREQUAL "Thread") 514 append_common_sanitizer_flags() 515 append("-fsanitize=thread" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 516 elseif (LLVM_USE_SANITIZER STREQUAL "Address;Undefined" OR 517 LLVM_USE_SANITIZER STREQUAL "Undefined;Address") 518 append_common_sanitizer_flags() 519 append("-fsanitize=address,undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all" 520 CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 521 else() 522 message(FATAL_ERROR "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}") 523 endif() 524 elseif(MSVC) 525 if (LLVM_USE_SANITIZER STREQUAL "Address") 526 append_common_sanitizer_flags() 527 append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 528 else() 529 message(FATAL_ERROR "This sanitizer not yet supported in the MSVC environment: ${LLVM_USE_SANITIZER}") 530 endif() 531 else() 532 message(FATAL_ERROR "LLVM_USE_SANITIZER is not supported on this platform.") 533 endif() 534 if (LLVM_USE_SANITIZE_COVERAGE) 535 append("-fsanitize-coverage=edge,indirect-calls,8bit-counters,trace-cmp" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 536 endif() 537endif() 538 539# Turn on -gsplit-dwarf if requested 540if(LLVM_USE_SPLIT_DWARF) 541 add_definitions("-gsplit-dwarf") 542endif() 543 544add_llvm_definitions( -D__STDC_CONSTANT_MACROS ) 545add_llvm_definitions( -D__STDC_FORMAT_MACROS ) 546add_llvm_definitions( -D__STDC_LIMIT_MACROS ) 547 548# clang doesn't print colored diagnostics when invoked from Ninja 549if (UNIX AND 550 CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND 551 CMAKE_GENERATOR STREQUAL "Ninja") 552 append("-fcolor-diagnostics" CMAKE_C_FLAGS CMAKE_CXX_FLAGS) 553endif() 554 555# Add flags for add_dead_strip(). 556# FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF? 557# But MinSizeRel seems to add that automatically, so maybe disable these 558# flags instead if LLVM_NO_DEAD_STRIP is set. 559if(NOT CYGWIN AND NOT WIN32) 560 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin" AND 561 NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") 562 check_c_compiler_flag("-Werror -fno-function-sections" C_SUPPORTS_FNO_FUNCTION_SECTIONS) 563 if (C_SUPPORTS_FNO_FUNCTION_SECTIONS) 564 # Don't add -ffunction-section if it can be disabled with -fno-function-sections. 565 # Doing so will break sanitizers. 566 add_flag_if_supported("-ffunction-sections" FFUNCTION_SECTIONS) 567 endif() 568 add_flag_if_supported("-fdata-sections" FDATA_SECTIONS) 569 endif() 570endif() 571 572if(CYGWIN OR MINGW) 573 # Prune --out-implib from executables. It doesn't make sense even 574 # with --export-all-symbols. 575 string(REGEX REPLACE "-Wl,--out-implib,[^ ]+ " " " 576 CMAKE_C_LINK_EXECUTABLE "${CMAKE_C_LINK_EXECUTABLE}") 577 string(REGEX REPLACE "-Wl,--out-implib,[^ ]+ " " " 578 CMAKE_CXX_LINK_EXECUTABLE "${CMAKE_CXX_LINK_EXECUTABLE}") 579endif() 580 581if(MSVC) 582 # Remove flags here, for exceptions and RTTI. 583 # Each target property or source property should be responsible to control 584 # them. 585 # CL.EXE complains to override flags like "/GR /GR-". 586 string(REGEX REPLACE "(^| ) */EH[-cs]+ *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}") 587 string(REGEX REPLACE "(^| ) */GR-? *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}") 588endif() 589 590# Provide public options to globally control RTTI and EH 591option(LLVM_ENABLE_EH "Enable Exception handling" OFF) 592option(LLVM_ENABLE_RTTI "Enable run time type information" OFF) 593if(LLVM_ENABLE_EH AND NOT LLVM_ENABLE_RTTI) 594 message(FATAL_ERROR "Exception handling requires RTTI. You must set LLVM_ENABLE_RTTI to ON") 595endif() 596 597option(LLVM_BUILD_INSTRUMENTED "Build LLVM and tools with PGO instrumentation (experimental)" Off) 598mark_as_advanced(LLVM_BUILD_INSTRUMENTED) 599append_if(LLVM_BUILD_INSTRUMENTED "-fprofile-instr-generate" 600 CMAKE_CXX_FLAGS 601 CMAKE_C_FLAGS 602 CMAKE_EXE_LINKER_FLAGS 603 CMAKE_SHARED_LINKER_FLAGS) 604 605# Plugin support 606# FIXME: Make this configurable. 607if(WIN32 OR CYGWIN) 608 if(BUILD_SHARED_LIBS) 609 set(LLVM_ENABLE_PLUGINS ON) 610 else() 611 set(LLVM_ENABLE_PLUGINS OFF) 612 endif() 613else() 614 set(LLVM_ENABLE_PLUGINS ON) 615endif() 616