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 "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE)
8
9include(CheckCompilerVersion)
10include(HandleLLVMStdlib)
11include(CheckCCompilerFlag)
12include(CheckCXXCompilerFlag)
13
14if(CMAKE_LINKER MATCHES "lld-link\.exe" OR (WIN32 AND LLVM_USE_LINKER STREQUAL "lld") OR LLVM_ENABLE_LLD)
15  set(LINKER_IS_LLD_LINK TRUE)
16else()
17  set(LINKER_IS_LLD_LINK FALSE)
18endif()
19
20set(LLVM_ENABLE_LTO OFF CACHE STRING "Build LLVM with LTO. May be specified as Thin or Full to use a particular kind of LTO")
21string(TOUPPER "${LLVM_ENABLE_LTO}" uppercase_LLVM_ENABLE_LTO)
22
23# Ninja Job Pool support
24# The following only works with the Ninja generator in CMake >= 3.0.
25set(LLVM_PARALLEL_COMPILE_JOBS "" CACHE STRING
26  "Define the maximum number of concurrent compilation jobs (Ninja only).")
27if(LLVM_PARALLEL_COMPILE_JOBS)
28  if(NOT CMAKE_MAKE_PROGRAM MATCHES "ninja")
29    message(WARNING "Job pooling is only available with Ninja generators.")
30  else()
31    set_property(GLOBAL APPEND PROPERTY JOB_POOLS compile_job_pool=${LLVM_PARALLEL_COMPILE_JOBS})
32    set(CMAKE_JOB_POOL_COMPILE compile_job_pool)
33  endif()
34endif()
35
36set(LLVM_PARALLEL_LINK_JOBS "" CACHE STRING
37  "Define the maximum number of concurrent link jobs (Ninja only).")
38if(CMAKE_MAKE_PROGRAM MATCHES "ninja")
39  if(NOT LLVM_PARALLEL_LINK_JOBS AND uppercase_LLVM_ENABLE_LTO STREQUAL "THIN")
40    message(STATUS "ThinLTO provides its own parallel linking - limiting parallel link jobs to 2.")
41    set(LLVM_PARALLEL_LINK_JOBS "2")
42  endif()
43  if(LLVM_PARALLEL_LINK_JOBS)
44    set_property(GLOBAL APPEND PROPERTY JOB_POOLS link_job_pool=${LLVM_PARALLEL_LINK_JOBS})
45    set(CMAKE_JOB_POOL_LINK link_job_pool)
46  endif()
47elseif(LLVM_PARALLEL_LINK_JOBS)
48  message(WARNING "Job pooling is only available with Ninja generators.")
49endif()
50
51if( LLVM_ENABLE_ASSERTIONS )
52  # MSVC doesn't like _DEBUG on release builds. See PR 4379.
53  if( NOT MSVC )
54    add_definitions( -D_DEBUG )
55  endif()
56  # On non-Debug builds cmake automatically defines NDEBUG, so we
57  # explicitly undefine it:
58  if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )
59    add_definitions( -UNDEBUG )
60    # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines.
61    foreach (flags_var_to_scrub
62        CMAKE_CXX_FLAGS_RELEASE
63        CMAKE_CXX_FLAGS_RELWITHDEBINFO
64        CMAKE_CXX_FLAGS_MINSIZEREL
65        CMAKE_C_FLAGS_RELEASE
66        CMAKE_C_FLAGS_RELWITHDEBINFO
67        CMAKE_C_FLAGS_MINSIZEREL)
68      string (REGEX REPLACE "(^| )[/-]D *NDEBUG($| )" " "
69        "${flags_var_to_scrub}" "${${flags_var_to_scrub}}")
70    endforeach()
71  endif()
72endif()
73
74if(LLVM_ENABLE_EXPENSIVE_CHECKS)
75  add_definitions(-DEXPENSIVE_CHECKS)
76  add_definitions(-D_GLIBCXX_DEBUG)
77endif()
78
79string(TOUPPER "${LLVM_ABI_BREAKING_CHECKS}" uppercase_LLVM_ABI_BREAKING_CHECKS)
80
81if( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "WITH_ASSERTS" )
82  if( LLVM_ENABLE_ASSERTIONS )
83    set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 )
84  endif()
85elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_ON" )
86  set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 )
87elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_OFF" )
88  # We don't need to do anything special to turn off ABI breaking checks.
89elseif( NOT DEFINED LLVM_ABI_BREAKING_CHECKS )
90  # Treat LLVM_ABI_BREAKING_CHECKS like "FORCE_OFF" when it has not been
91  # defined.
92else()
93  message(FATAL_ERROR "Unknown value for LLVM_ABI_BREAKING_CHECKS: \"${LLVM_ABI_BREAKING_CHECKS}\"!")
94endif()
95
96if( LLVM_REVERSE_ITERATION )
97  set( LLVM_ENABLE_REVERSE_ITERATION 1 )
98endif()
99
100if(WIN32)
101  set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
102  if(CYGWIN)
103    set(LLVM_ON_WIN32 0)
104    set(LLVM_ON_UNIX 1)
105  else(CYGWIN)
106    set(LLVM_ON_WIN32 1)
107    set(LLVM_ON_UNIX 0)
108  endif(CYGWIN)
109else(WIN32)
110  if(FUCHSIA OR UNIX)
111    set(LLVM_ON_WIN32 0)
112    set(LLVM_ON_UNIX 1)
113    if(APPLE OR ${CMAKE_SYSTEM_NAME} MATCHES "AIX")
114      set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
115    else()
116      set(LLVM_HAVE_LINK_VERSION_SCRIPT 1)
117    endif()
118  else(FUCHSIA OR UNIX)
119    MESSAGE(SEND_ERROR "Unable to determine platform")
120  endif(FUCHSIA OR UNIX)
121endif(WIN32)
122
123set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX})
124set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
125
126# We use *.dylib rather than *.so on darwin.
127set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
128
129if(APPLE)
130  if(LLVM_ENABLE_LLD AND LLVM_ENABLE_LTO)
131    message(FATAL_ERROR "lld does not support LTO on Darwin")
132  endif()
133  # Darwin-specific linker flags for loadable modules.
134  set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-flat_namespace -Wl,-undefined -Wl,suppress")
135endif()
136
137# Pass -Wl,-z,defs. This makes sure all symbols are defined. Otherwise a DSO
138# build might work on ELF but fail on MachO/COFF.
139if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin" OR WIN32 OR CYGWIN OR
140        ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR
141        ${CMAKE_SYSTEM_NAME} MATCHES "OpenBSD") AND
142   NOT LLVM_USE_SANITIZER)
143  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,defs")
144endif()
145
146# Pass -Wl,-z,nodelete. This makes sure our shared libraries are not unloaded
147# by dlclose(). We need that since the CLI API relies on cross-references
148# between global objects which became horribly broken when one of the libraries
149# is unloaded.
150if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
151  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,nodelete")
152  set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-z,nodelete")
153endif()
154
155
156function(append value)
157  foreach(variable ${ARGN})
158    set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
159  endforeach(variable)
160endfunction()
161
162function(append_if condition value)
163  if (${condition})
164    foreach(variable ${ARGN})
165      set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
166    endforeach(variable)
167  endif()
168endfunction()
169
170macro(add_flag_if_supported flag name)
171  check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}")
172  append_if("C_SUPPORTS_${name}" "${flag}" CMAKE_C_FLAGS)
173  check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}")
174  append_if("CXX_SUPPORTS_${name}" "${flag}" CMAKE_CXX_FLAGS)
175endmacro()
176
177function(add_flag_or_print_warning flag name)
178  check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}")
179  check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}")
180  if (C_SUPPORTS_${name} AND CXX_SUPPORTS_${name})
181    message(STATUS "Building with ${flag}")
182    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE)
183    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE)
184    set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${flag}" PARENT_SCOPE)
185  else()
186    message(WARNING "${flag} is not supported.")
187  endif()
188endfunction()
189
190if( LLVM_ENABLE_LLD )
191	if ( LLVM_USE_LINKER )
192		message(FATAL_ERROR "LLVM_ENABLE_LLD and LLVM_USE_LINKER can't be set at the same time")
193	endif()
194	set(LLVM_USE_LINKER "lld")
195endif()
196
197if( LLVM_USE_LINKER )
198  set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
199  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -fuse-ld=${LLVM_USE_LINKER}")
200  check_cxx_source_compiles("int main() { return 0; }" CXX_SUPPORTS_CUSTOM_LINKER)
201  if ( NOT CXX_SUPPORTS_CUSTOM_LINKER )
202	  message(FATAL_ERROR "Host compiler does not support '-fuse-ld=${LLVM_USE_LINKER}'")
203  endif()
204  set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
205  append("-fuse-ld=${LLVM_USE_LINKER}"
206    CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
207endif()
208
209if( LLVM_ENABLE_PIC )
210  if( XCODE )
211    # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
212    # know how to disable this, so just force ENABLE_PIC off for now.
213    message(WARNING "-fPIC not supported with Xcode.")
214  elseif( WIN32 OR CYGWIN)
215    # On Windows all code is PIC. MinGW warns if -fPIC is used.
216  else()
217    add_flag_or_print_warning("-fPIC" FPIC)
218  endif()
219endif()
220
221if(NOT WIN32 AND NOT CYGWIN)
222  # MinGW warns if -fvisibility-inlines-hidden is used.
223  check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG)
224  append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS)
225endif()
226
227if(CMAKE_SIZEOF_VOID_P EQUAL 8 AND MINGW)
228  add_definitions( -D_FILE_OFFSET_BITS=64 )
229endif()
230
231if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
232  # TODO: support other platforms and toolchains.
233  if( LLVM_BUILD_32_BITS )
234    message(STATUS "Building 32 bits executables and libraries.")
235    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -m32")
236    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -m32")
237    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32")
238    set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32")
239    set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32")
240
241    # FIXME: CMAKE_SIZEOF_VOID_P is still 8
242    add_definitions(-D_LARGEFILE_SOURCE)
243    add_definitions(-D_FILE_OFFSET_BITS=64)
244  endif( LLVM_BUILD_32_BITS )
245endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
246
247# If building on a GNU specific 32-bit system, make sure off_t is 64 bits
248# so that off_t can stored offset > 2GB.
249# Android until version N (API 24) doesn't support it.
250if (ANDROID AND (ANDROID_NATIVE_API_LEVEL LESS 24))
251  set(LLVM_FORCE_SMALLFILE_FOR_ANDROID TRUE)
252endif()
253if( CMAKE_SIZEOF_VOID_P EQUAL 4 AND NOT LLVM_FORCE_SMALLFILE_FOR_ANDROID)
254  # FIXME: It isn't handled in LLVM_BUILD_32_BITS.
255  add_definitions( -D_LARGEFILE_SOURCE )
256  add_definitions( -D_FILE_OFFSET_BITS=64 )
257endif()
258
259if( XCODE )
260  # For Xcode enable several build settings that correspond to
261  # many warnings that are on by default in Clang but are
262  # not enabled for historical reasons.  For versions of Xcode
263  # that do not support these options they will simply
264  # be ignored.
265  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_RETURN_TYPE "YES")
266  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_MISSING_NEWLINE "YES")
267  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VALUE "YES")
268  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VARIABLE "YES")
269  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_SIGN_COMPARE "YES")
270  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_FUNCTION "YES")
271  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_INITIALIZER_NOT_FULLY_BRACKETED "YES")
272  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_HIDDEN_VIRTUAL_FUNCTIONS "YES")
273  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNINITIALIZED_AUTOS "YES")
274  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_BOOL_CONVERSION "YES")
275  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_EMPTY_BODY "YES")
276  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_ENUM_CONVERSION "YES")
277  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_INT_CONVERSION "YES")
278  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_CONSTANT_CONVERSION "YES")
279  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_NON_VIRTUAL_DESTRUCTOR "YES")
280endif()
281
282# On Win32 using MS tools, provide an option to set the number of parallel jobs
283# to use.
284if( MSVC_IDE )
285  set(LLVM_COMPILER_JOBS "0" CACHE STRING
286    "Number of parallel compiler jobs. 0 means use all processors. Default is 0.")
287  if( NOT LLVM_COMPILER_JOBS STREQUAL "1" )
288    if( LLVM_COMPILER_JOBS STREQUAL "0" )
289      add_definitions( /MP )
290    else()
291      message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS})
292      add_definitions( /MP${LLVM_COMPILER_JOBS} )
293    endif()
294  else()
295    message(STATUS "Parallel compilation disabled")
296  endif()
297endif()
298
299# set stack reserved size to ~10MB
300if(MSVC)
301  # CMake previously automatically set this value for MSVC builds, but the
302  # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default
303  # value (1 MB) which is not enough for us in tasks such as parsing recursive
304  # C++ templates in Clang.
305  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} /STACK:10000000")
306elseif(MINGW) # FIXME: Also cygwin?
307  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--stack,16777216")
308
309  # Pass -mbig-obj to mingw gas on Win64. COFF has a 2**16 section limit, and
310  # on Win64, every COMDAT function creates at least 3 sections: .text, .pdata,
311  # and .xdata.
312  if (CMAKE_SIZEOF_VOID_P EQUAL 8)
313    append("-Wa,-mbig-obj" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
314  endif()
315endif()
316
317if( MSVC )
318  if( CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.0 )
319    # For MSVC 2013, disable iterator null pointer checking in debug mode,
320    # especially so std::equal(nullptr, nullptr, nullptr) will not assert.
321    add_definitions("-D_DEBUG_POINTER_IMPL=")
322  endif()
323
324  include(ChooseMSVCCRT)
325
326  if( MSVC11 )
327    add_definitions(-D_VARIADIC_MAX=10)
328  endif()
329
330  # Add definitions that make MSVC much less annoying.
331  add_definitions(
332    # For some reason MS wants to deprecate a bunch of standard functions...
333    -D_CRT_SECURE_NO_DEPRECATE
334    -D_CRT_SECURE_NO_WARNINGS
335    -D_CRT_NONSTDC_NO_DEPRECATE
336    -D_CRT_NONSTDC_NO_WARNINGS
337    -D_SCL_SECURE_NO_DEPRECATE
338    -D_SCL_SECURE_NO_WARNINGS
339    )
340
341  # Tell MSVC to use the Unicode version of the Win32 APIs instead of ANSI.
342  add_definitions(
343    -DUNICODE
344    -D_UNICODE
345  )
346
347  if (LLVM_ENABLE_WERROR)
348    append("/WX" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
349  endif (LLVM_ENABLE_WERROR)
350
351  append("/Zc:inline" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
352
353  # Allow users to request PDBs in release mode. CMake offeres the
354  # RelWithDebInfo configuration, but it uses different optimization settings
355  # (/Ob1 vs /Ob2 or -O2 vs -O3). LLVM provides this flag so that users can get
356  # PDBs without changing codegen.
357  option(LLVM_ENABLE_PDB OFF)
358  if (LLVM_ENABLE_PDB AND uppercase_CMAKE_BUILD_TYPE STREQUAL "RELEASE")
359    append("/Zi" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
360    # /DEBUG disables linker GC and ICF, but we want those in Release mode.
361    append("/DEBUG /OPT:REF /OPT:ICF"
362          CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS
363          CMAKE_SHARED_LINKER_FLAGS)
364  endif()
365
366  # /Zc:strictStrings is incompatible with VS12's (Visual Studio 2013's)
367  # debug mode headers. Instead of only enabling them in VS2013's debug mode,
368  # we'll just enable them for Visual Studio 2015 (VS 14, MSVC_VERSION 1900)
369  # and up.
370  if (NOT (MSVC_VERSION LESS 1900))
371    # Disable string literal const->non-const type conversion.
372    # "When specified, the compiler requires strict const-qualification
373    # conformance for pointers initialized by using string literals."
374    append("/Zc:strictStrings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
375  endif(NOT (MSVC_VERSION LESS 1900))
376
377  # "Generate Intrinsic Functions".
378  append("/Oi" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
379
380  # "Enforce type conversion rules".
381  append("/Zc:rvalueCast" CMAKE_CXX_FLAGS)
382
383  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT LLVM_ENABLE_LTO)
384    # clang-cl and cl by default produce non-deterministic binaries because
385    # link.exe /incremental requires a timestamp in the .obj file.  clang-cl
386    # has the flag /Brepro to force deterministic binaries. We want to pass that
387    # whenever you're building with clang unless you're passing /incremental
388    # or using LTO (/Brepro with LTO would result in a warning about the flag
389    # being unused, because we're not generating object files).
390    # This checks CMAKE_CXX_COMPILER_ID in addition to check_cxx_compiler_flag()
391    # because cl.exe does not emit an error on flags it doesn't understand,
392    # letting check_cxx_compiler_flag() claim it understands all flags.
393    check_cxx_compiler_flag("/Brepro" SUPPORTS_BREPRO)
394    if (SUPPORTS_BREPRO)
395      # Check if /INCREMENTAL is passed to the linker and complain that it
396      # won't work with /Brepro.
397      string(TOUPPER "${CMAKE_EXE_LINKER_FLAGS}" upper_exe_flags)
398      string(TOUPPER "${CMAKE_MODULE_LINKER_FLAGS}" upper_module_flags)
399      string(TOUPPER "${CMAKE_SHARED_LINKER_FLAGS}" upper_shared_flags)
400
401      string(FIND "${upper_exe_flags} ${upper_module_flags} ${upper_shared_flags}"
402        "/INCREMENTAL" linker_flag_idx)
403
404      if (${linker_flag_idx} GREATER -1)
405        message(WARNING "/Brepro not compatible with /INCREMENTAL linking - builds will be non-deterministic")
406      else()
407        append("/Brepro" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
408      endif()
409    endif()
410  endif()
411
412elseif( LLVM_COMPILER_IS_GCC_COMPATIBLE )
413  append_if(LLVM_ENABLE_WERROR "-Werror" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
414  append_if(LLVM_ENABLE_WERROR "-Wno-error" CMAKE_REQUIRED_FLAGS)
415  add_flag_if_supported("-Werror=date-time" WERROR_DATE_TIME)
416  add_flag_if_supported("-Werror=unguarded-availability-new" WERROR_UNGUARDED_AVAILABILITY_NEW)
417  if (LLVM_ENABLE_CXX1Y)
418    check_cxx_compiler_flag("-std=c++1y" CXX_SUPPORTS_CXX1Y)
419    append_if(CXX_SUPPORTS_CXX1Y "-std=c++1y" CMAKE_CXX_FLAGS)
420  elseif(LLVM_ENABLE_CXX1Z)
421    check_cxx_compiler_flag("-std=c++1z" CXX_SUPPORTS_CXX1Z)
422    append_if(CXX_SUPPORTS_CXX1Z "-std=c++1z" CMAKE_CXX_FLAGS)
423  else()
424    check_cxx_compiler_flag("-std=c++11" CXX_SUPPORTS_CXX11)
425    if (CXX_SUPPORTS_CXX11)
426      if (CYGWIN OR MINGW)
427        # MinGW and Cygwin are a bit stricter and lack things like
428        # 'strdup', 'stricmp', etc in c++11 mode.
429        append("-std=gnu++11" CMAKE_CXX_FLAGS)
430      else()
431        append("-std=c++11" CMAKE_CXX_FLAGS)
432      endif()
433    else()
434      message(FATAL_ERROR "LLVM requires C++11 support but the '-std=c++11' flag isn't supported.")
435    endif()
436  endif()
437  if (LLVM_ENABLE_MODULES)
438    set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
439    set(module_flags "-fmodules -fmodules-cache-path=${PROJECT_BINARY_DIR}/module.cache")
440    if (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
441      # On Darwin -fmodules does not imply -fcxx-modules.
442      set(module_flags "${module_flags} -fcxx-modules")
443    endif()
444    if (LLVM_ENABLE_LOCAL_SUBMODULE_VISIBILITY)
445      set(module_flags "${module_flags} -Xclang -fmodules-local-submodule-visibility")
446    endif()
447    if (LLVM_ENABLE_MODULE_DEBUGGING AND
448        ((uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") OR
449         (uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")))
450      set(module_flags "${module_flags} -gmodules")
451    endif()
452    set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${module_flags}")
453
454    # Check that we can build code with modules enabled, and that repeatedly
455    # including <cassert> still manages to respect NDEBUG properly.
456    CHECK_CXX_SOURCE_COMPILES("#undef NDEBUG
457                               #include <cassert>
458                               #define NDEBUG
459                               #include <cassert>
460                               int main() { assert(this code is not compiled); }"
461                               CXX_SUPPORTS_MODULES)
462    set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
463    if (CXX_SUPPORTS_MODULES)
464      append("${module_flags}" CMAKE_CXX_FLAGS)
465    else()
466      message(FATAL_ERROR "LLVM_ENABLE_MODULES is not supported by this compiler")
467    endif()
468  endif(LLVM_ENABLE_MODULES)
469endif( MSVC )
470
471if (MSVC)
472  if (NOT CLANG_CL)
473    set(msvc_warning_flags
474      # Disabled warnings.
475      -wd4141 # Suppress ''modifier' : used more than once' (because of __forceinline combined with inline)
476      -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned'
477      -wd4180 # Suppress 'qualifier applied to function type has no meaning; ignored'
478      -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data'
479      -wd4258 # Suppress ''var' : definition from the for loop is ignored; the definition from the enclosing scope is used'
480      -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data'
481      -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception'
482      -wd4345 # Suppress 'behavior change: an object of POD type constructed with an initializer of the form () will be default-initialized'
483      -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized'
484      -wd4355 # Suppress ''this' : used in base member initializer list'
485      -wd4456 # Suppress 'declaration of 'var' hides local variable'
486      -wd4457 # Suppress 'declaration of 'var' hides function parameter'
487      -wd4458 # Suppress 'declaration of 'var' hides class member'
488      -wd4459 # Suppress 'declaration of 'var' hides global declaration'
489      -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated'
490      -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible'
491      -wd4722 # Suppress 'function' : destructor never returns, potential memory leak
492      -wd4800 # Suppress ''type' : forcing value to bool 'true' or 'false' (performance warning)'
493      -wd4100 # Suppress 'unreferenced formal parameter'
494      -wd4127 # Suppress 'conditional expression is constant'
495      -wd4512 # Suppress 'assignment operator could not be generated'
496      -wd4505 # Suppress 'unreferenced local function has been removed'
497      -wd4610 # Suppress '<class> can never be instantiated'
498      -wd4510 # Suppress 'default constructor could not be generated'
499      -wd4702 # Suppress 'unreachable code'
500      -wd4245 # Suppress 'signed/unsigned mismatch'
501      -wd4706 # Suppress 'assignment within conditional expression'
502      -wd4310 # Suppress 'cast truncates constant value'
503      -wd4701 # Suppress 'potentially uninitialized local variable'
504      -wd4703 # Suppress 'potentially uninitialized local pointer variable'
505      -wd4389 # Suppress 'signed/unsigned mismatch'
506      -wd4611 # Suppress 'interaction between '_setjmp' and C++ object destruction is non-portable'
507      -wd4805 # Suppress 'unsafe mix of type <type> and type <type> in operation'
508      -wd4204 # Suppress 'nonstandard extension used : non-constant aggregate initializer'
509      -wd4577 # Suppress 'noexcept used with no exception handling mode specified; termination on exception is not guaranteed'
510      -wd4091 # Suppress 'typedef: ignored on left of '' when no variable is declared'
511          # C4592 is disabled because of false positives in Visual Studio 2015
512          # Update 1. Re-evaluate the usefulness of this diagnostic with Update 2.
513      -wd4592 # Suppress ''var': symbol will be dynamically initialized (implementation limitation)
514      -wd4319 # Suppress ''operator' : zero extending 'type' to 'type' of greater size'
515
516      # Ideally, we'd like this warning to be enabled, but MSVC 2013 doesn't
517      # support the 'aligned' attribute in the way that clang sources requires (for
518      # any code that uses the LLVM_ALIGNAS macro), so this is must be disabled to
519      # avoid unwanted alignment warnings.
520      # When we switch to requiring a version of MSVC that supports the 'alignas'
521      # specifier (MSVC 2015?) this warning can be re-enabled.
522      -wd4324 # Suppress 'structure was padded due to __declspec(align())'
523
524      # Promoted warnings.
525      -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning.
526
527      # Promoted warnings to errors.
528      -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error.
529      )
530  endif(NOT CLANG_CL)
531
532  # Enable warnings
533  if (LLVM_ENABLE_WARNINGS)
534    # Put /W4 in front of all the -we flags. cl.exe doesn't care, but for
535    # clang-cl having /W4 after the -we flags will re-enable the warnings
536    # disabled by -we.
537    set(msvc_warning_flags "/W4 ${msvc_warning_flags}")
538    # CMake appends /W3 by default, and having /W3 followed by /W4 will result in
539    # cl : Command line warning D9025 : overriding '/W3' with '/W4'.  Since this is
540    # a command line warning and not a compiler warning, it cannot be suppressed except
541    # by fixing the command line.
542    string(REGEX REPLACE " /W[0-4]" "" CMAKE_C_FLAGS "${CMAKE_C_FLAGS}")
543    string(REGEX REPLACE " /W[0-4]" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
544
545    if (LLVM_ENABLE_PEDANTIC)
546      # No MSVC equivalent available
547    endif (LLVM_ENABLE_PEDANTIC)
548  endif (LLVM_ENABLE_WARNINGS)
549
550  foreach(flag ${msvc_warning_flags})
551    append("${flag}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
552  endforeach(flag)
553endif (MSVC)
554
555if (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
556
557  # Don't add -Wall for clang-cl, because it maps -Wall to -Weverything for
558  # MSVC compatibility.  /W4 is added above instead.
559  if (NOT CLANG_CL)
560    append("-Wall" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
561  endif()
562
563  append("-Wextra -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
564  append("-Wcast-qual" CMAKE_CXX_FLAGS)
565
566  # Turn off missing field initializer warnings for gcc to avoid noise from
567  # false positives with empty {}. Turn them on otherwise (they're off by
568  # default for clang).
569  check_cxx_compiler_flag("-Wmissing-field-initializers" CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
570  if (CXX_SUPPORTS_MISSING_FIELD_INITIALIZERS_FLAG)
571    if (CMAKE_COMPILER_IS_GNUCXX)
572      append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
573    else()
574      append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
575    endif()
576  endif()
577
578  if (LLVM_ENABLE_PEDANTIC AND LLVM_COMPILER_IS_GCC_COMPATIBLE)
579    append("-pedantic" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
580    append("-Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
581  endif()
582
583  add_flag_if_supported("-Wcovered-switch-default" COVERED_SWITCH_DEFAULT_FLAG)
584  append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS)
585  append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS)
586
587  # Disable -Wclass-memaccess, a C++-only warning from GCC 8 that fires on
588  # LLVM's ADT classes.
589  check_cxx_compiler_flag("-Wclass-memaccess" CXX_SUPPORTS_CLASS_MEMACCESS_FLAG)
590  append_if(CXX_SUPPORTS_CLASS_MEMACCESS_FLAG "-Wno-class-memaccess" CMAKE_CXX_FLAGS)
591
592  # The LLVM libraries have no stable C++ API, so -Wnoexcept-type is not useful.
593  check_cxx_compiler_flag("-Wnoexcept-type" CXX_SUPPORTS_NOEXCEPT_TYPE_FLAG)
594  append_if(CXX_SUPPORTS_NOEXCEPT_TYPE_FLAG "-Wno-noexcept-type" CMAKE_CXX_FLAGS)
595
596  # Check if -Wnon-virtual-dtor warns even though the class is marked final.
597  # If it does, don't add it. So it won't be added on clang 3.4 and older.
598  # This also catches cases when -Wnon-virtual-dtor isn't supported by
599  # the compiler at all.  This flag is not activated for gcc since it will
600  # incorrectly identify a protected non-virtual base when there is a friend
601  # declaration. Don't activate this in general on Windows as this warning has
602  # too many false positives on COM-style classes, which are destroyed with
603  # Release() (PR32286).
604  if (NOT CMAKE_COMPILER_IS_GNUCXX AND NOT WIN32)
605    set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
606    set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++11 -Werror=non-virtual-dtor")
607    CHECK_CXX_SOURCE_COMPILES("class base {public: virtual void anchor();protected: ~base();};
608                               class derived final : public base { public: ~derived();};
609                               int main() { return 0; }"
610                              CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR)
611    set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
612    append_if(CXX_WONT_WARN_ON_FINAL_NONVIRTUALDTOR
613              "-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
614  endif()
615
616  # Enable -Wdelete-non-virtual-dtor if available.
617  add_flag_if_supported("-Wdelete-non-virtual-dtor" DELETE_NON_VIRTUAL_DTOR_FLAG)
618
619  # Check if -Wcomment is OK with an // comment ending with '\' if the next
620  # line is also a // comment.
621  set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
622  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror -Wcomment")
623  CHECK_C_SOURCE_COMPILES("// \\\\\\n//\\nint main() {return 0;}"
624                          C_WCOMMENT_ALLOWS_LINE_WRAP)
625  set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
626  if (NOT C_WCOMMENT_ALLOWS_LINE_WRAP)
627    append("-Wno-comment" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
628  endif()
629
630  # Enable -Wstring-conversion to catch misuse of string literals.
631  add_flag_if_supported("-Wstring-conversion" STRING_CONVERSION_FLAG)
632endif (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
633
634if (LLVM_COMPILER_IS_GCC_COMPATIBLE AND NOT LLVM_ENABLE_WARNINGS)
635  append("-w" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
636endif()
637
638macro(append_common_sanitizer_flags)
639  if (NOT MSVC)
640    # Append -fno-omit-frame-pointer and turn on debug info to get better
641    # stack traces.
642    add_flag_if_supported("-fno-omit-frame-pointer" FNO_OMIT_FRAME_POINTER)
643    if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND
644        NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")
645      add_flag_if_supported("-gline-tables-only" GLINE_TABLES_ONLY)
646    endif()
647    # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large.
648    if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND LLVM_OPTIMIZE_SANITIZED_BUILDS)
649      add_flag_if_supported("-O1" O1)
650    endif()
651  elseif (CLANG_CL)
652    # Keep frame pointers around.
653    append("/Oy-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
654    if (LINKER_IS_LLD_LINK)
655      # Use DWARF debug info with LLD.
656      append("-gdwarf" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
657    else()
658      # Enable codeview otherwise.
659      append("/Z7" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
660    endif()
661    # Always ask the linker to produce symbols with asan.
662    append("-debug" CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
663  endif()
664endmacro()
665
666# Turn on sanitizers if necessary.
667if(LLVM_USE_SANITIZER)
668  if (LLVM_ON_UNIX)
669    if (LLVM_USE_SANITIZER STREQUAL "Address")
670      append_common_sanitizer_flags()
671      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
672    elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?")
673      append_common_sanitizer_flags()
674      append("-fsanitize=memory" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
675      if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins")
676        append("-fsanitize-memory-track-origins" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
677      endif()
678    elseif (LLVM_USE_SANITIZER STREQUAL "Undefined")
679      append_common_sanitizer_flags()
680      append("-fsanitize=undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all"
681              CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
682    elseif (LLVM_USE_SANITIZER STREQUAL "Thread")
683      append_common_sanitizer_flags()
684      append("-fsanitize=thread" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
685    elseif (LLVM_USE_SANITIZER STREQUAL "Address;Undefined" OR
686            LLVM_USE_SANITIZER STREQUAL "Undefined;Address")
687      append_common_sanitizer_flags()
688      append("-fsanitize=address,undefined -fno-sanitize=vptr,function -fno-sanitize-recover=all"
689              CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
690    elseif (LLVM_USE_SANITIZER STREQUAL "Leaks")
691      append_common_sanitizer_flags()
692      append("-fsanitize=leak" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
693    else()
694      message(FATAL_ERROR "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}")
695    endif()
696  elseif(MSVC)
697    if (LLVM_USE_SANITIZER STREQUAL "Address")
698      append_common_sanitizer_flags()
699      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
700    else()
701      message(FATAL_ERROR "This sanitizer not yet supported in the MSVC environment: ${LLVM_USE_SANITIZER}")
702    endif()
703  else()
704    message(FATAL_ERROR "LLVM_USE_SANITIZER is not supported on this platform.")
705  endif()
706  if (LLVM_USE_SANITIZER MATCHES "(Undefined;)?Address(;Undefined)?")
707    add_flag_if_supported("-fsanitize-address-use-after-scope"
708                          FSANITIZE_USE_AFTER_SCOPE_FLAG)
709  endif()
710  if (LLVM_USE_SANITIZE_COVERAGE)
711    append("-fsanitize=fuzzer-no-link" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
712  endif()
713  if (LLVM_USE_SANITIZER MATCHES ".*Undefined.*")
714    set(BLACKLIST_FILE "${CMAKE_SOURCE_DIR}/utils/sanitizers/ubsan_blacklist.txt")
715    if (EXISTS "${BLACKLIST_FILE}")
716      append("-fsanitize-blacklist=${BLACKLIST_FILE}"
717             CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
718    endif()
719  endif()
720endif()
721
722# Turn on -gsplit-dwarf if requested
723if(LLVM_USE_SPLIT_DWARF)
724  add_definitions("-gsplit-dwarf")
725endif()
726
727add_definitions( -D__STDC_CONSTANT_MACROS )
728add_definitions( -D__STDC_FORMAT_MACROS )
729add_definitions( -D__STDC_LIMIT_MACROS )
730
731# clang and gcc don't default-print colored diagnostics when invoked from Ninja.
732if (UNIX AND
733    CMAKE_GENERATOR STREQUAL "Ninja" AND
734    (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR
735     (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
736      NOT (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9))))
737  append("-fdiagnostics-color" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
738endif()
739
740# lld doesn't print colored diagnostics when invoked from Ninja
741if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja")
742  include(CheckLinkerFlag)
743  check_linker_flag("-Wl,--color-diagnostics" LINKER_SUPPORTS_COLOR_DIAGNOSTICS)
744  append_if(LINKER_SUPPORTS_COLOR_DIAGNOSTICS "-Wl,--color-diagnostics"
745    CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
746endif()
747
748# Add flags for add_dead_strip().
749# FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF?
750# But MinSizeRel seems to add that automatically, so maybe disable these
751# flags instead if LLVM_NO_DEAD_STRIP is set.
752if(NOT CYGWIN AND NOT WIN32)
753  if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin" AND
754     NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
755    check_c_compiler_flag("-Werror -fno-function-sections" C_SUPPORTS_FNO_FUNCTION_SECTIONS)
756    if (C_SUPPORTS_FNO_FUNCTION_SECTIONS)
757      # Don't add -ffunction-section if it can be disabled with -fno-function-sections.
758      # Doing so will break sanitizers.
759      add_flag_if_supported("-ffunction-sections" FFUNCTION_SECTIONS)
760    endif()
761    add_flag_if_supported("-fdata-sections" FDATA_SECTIONS)
762  endif()
763endif()
764
765if(MSVC)
766  # Remove flags here, for exceptions and RTTI.
767  # Each target property or source property should be responsible to control
768  # them.
769  # CL.EXE complains to override flags like "/GR /GR-".
770  string(REGEX REPLACE "(^| ) */EH[-cs]+ *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
771  string(REGEX REPLACE "(^| ) */GR-? *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
772endif()
773
774# Provide public options to globally control RTTI and EH
775option(LLVM_ENABLE_EH "Enable Exception handling" OFF)
776option(LLVM_ENABLE_RTTI "Enable run time type information" OFF)
777if(LLVM_ENABLE_EH AND NOT LLVM_ENABLE_RTTI)
778  message(FATAL_ERROR "Exception handling requires RTTI. You must set LLVM_ENABLE_RTTI to ON")
779endif()
780
781option(LLVM_ENABLE_IR_PGO "Build LLVM and tools with IR PGO instrumentation (deprecated)" Off)
782mark_as_advanced(LLVM_ENABLE_IR_PGO)
783
784set(LLVM_BUILD_INSTRUMENTED OFF CACHE STRING "Build LLVM and tools with PGO instrumentation. May be specified as IR or Frontend")
785mark_as_advanced(LLVM_BUILD_INSTRUMENTED)
786string(TOUPPER "${LLVM_BUILD_INSTRUMENTED}" uppercase_LLVM_BUILD_INSTRUMENTED)
787
788if (LLVM_BUILD_INSTRUMENTED)
789  if (LLVM_ENABLE_IR_PGO OR uppercase_LLVM_BUILD_INSTRUMENTED STREQUAL "IR")
790    append("-fprofile-generate='${LLVM_PROFILE_DATA_DIR}'"
791      CMAKE_CXX_FLAGS
792      CMAKE_C_FLAGS
793      CMAKE_EXE_LINKER_FLAGS
794      CMAKE_SHARED_LINKER_FLAGS)
795  else()
796    append("-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}'"
797      CMAKE_CXX_FLAGS
798      CMAKE_C_FLAGS
799      CMAKE_EXE_LINKER_FLAGS
800      CMAKE_SHARED_LINKER_FLAGS)
801  endif()
802endif()
803
804option(LLVM_BUILD_INSTRUMENTED_COVERAGE "Build LLVM and tools with Code Coverage instrumentation" Off)
805mark_as_advanced(LLVM_BUILD_INSTRUMENTED_COVERAGE)
806append_if(LLVM_BUILD_INSTRUMENTED_COVERAGE "-fprofile-instr-generate='${LLVM_PROFILE_FILE_PATTERN}' -fcoverage-mapping"
807  CMAKE_CXX_FLAGS
808  CMAKE_C_FLAGS
809  CMAKE_EXE_LINKER_FLAGS
810  CMAKE_SHARED_LINKER_FLAGS)
811
812if (LLVM_BUILD_INSTRUMENTED AND LLVM_BUILD_INSTRUMENTED_COVERAGE)
813  message(FATAL_ERROR "LLVM_BUILD_INSTRUMENTED and LLVM_BUILD_INSTRUMENTED_COVERAGE cannot both be specified")
814endif()
815
816if(LLVM_ENABLE_LTO AND LLVM_ON_WIN32 AND NOT LINKER_IS_LLD_LINK)
817  message(FATAL_ERROR "When compiling for Windows, LLVM_ENABLE_LTO requires using lld as the linker (point CMAKE_LINKER at lld-link.exe)")
818endif()
819if(uppercase_LLVM_ENABLE_LTO STREQUAL "THIN")
820  append("-flto=thin" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
821  if(NOT LINKER_IS_LLD_LINK)
822    append("-flto=thin" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
823  endif()
824  # If the linker supports it, enable the lto cache. This improves initial build
825  # time a little since we re-link a lot of the same objects, and significantly
826  # improves incremental build time.
827  # FIXME: We should move all this logic into the clang driver.
828  if(APPLE)
829    append("-Wl,-cache_path_lto,${PROJECT_BINARY_DIR}/lto.cache"
830           CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
831  elseif(UNIX AND LLVM_USE_LINKER STREQUAL "lld")
832    append("-Wl,--thinlto-cache-dir=${PROJECT_BINARY_DIR}/lto.cache"
833           CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
834  elseif(LLVM_USE_LINKER STREQUAL "gold")
835    append("-Wl,--plugin-opt,cache-dir=${PROJECT_BINARY_DIR}/lto.cache"
836           CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
837  endif()
838elseif(uppercase_LLVM_ENABLE_LTO STREQUAL "FULL")
839  append("-flto=full" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
840  if(NOT LINKER_IS_LLD_LINK)
841    append("-flto=full" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
842  endif()
843elseif(LLVM_ENABLE_LTO)
844  append("-flto" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
845  if(NOT LINKER_IS_LLD_LINK)
846    append("-flto" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
847  endif()
848endif()
849
850# This option makes utils/extract_symbols.py be used to determine the list of
851# symbols to export from LLVM tools. This is necessary when using MSVC if you
852# want to allow plugins, though note that the plugin has to explicitly link
853# against (exactly one) tool so we can't unilaterally turn on
854# LLVM_ENABLE_PLUGINS when it's enabled.
855option(LLVM_EXPORT_SYMBOLS_FOR_PLUGINS "Export symbols from LLVM tools so that plugins can import them" OFF)
856if(BUILD_SHARED_LIBS AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
857  message(FATAL_ERROR "BUILD_SHARED_LIBS not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS")
858endif()
859if(LLVM_LINK_LLVM_DYLIB AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
860  message(FATAL_ERROR "LLVM_LINK_LLVM_DYLIB not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS")
861endif()
862
863# Plugin support
864# FIXME: Make this configurable.
865if(WIN32 OR CYGWIN)
866  if(BUILD_SHARED_LIBS OR LLVM_BUILD_LLVM_DYLIB)
867    set(LLVM_ENABLE_PLUGINS ON)
868  else()
869    set(LLVM_ENABLE_PLUGINS OFF)
870  endif()
871else()
872  set(LLVM_ENABLE_PLUGINS ON)
873endif()
874
875# By default we should enable LLVM_ENABLE_IDE only for multi-configuration
876# generators. This option disables optional build system features that make IDEs
877# less usable.
878set(LLVM_ENABLE_IDE_default OFF)
879if (CMAKE_CONFIGURATION_TYPES)
880  set(LLVM_ENABLE_IDE_default ON)
881endif()
882option(LLVM_ENABLE_IDE
883       "Disable optional build system features that cause problems for IDE generators"
884       ${LLVM_ENABLE_IDE_default})
885if (CMAKE_CONFIGURATION_TYPES AND NOT LLVM_ENABLE_IDE)
886  message(WARNING "Disabling LLVM_ENABLE_IDE on multi-configuration generators is not recommended.")
887endif()
888
889function(get_compile_definitions)
890  get_directory_property(top_dir_definitions DIRECTORY ${CMAKE_SOURCE_DIR} COMPILE_DEFINITIONS)
891  foreach(definition ${top_dir_definitions})
892    if(DEFINED result)
893      string(APPEND result " -D${definition}")
894    else()
895      set(result "-D${definition}")
896    endif()
897  endforeach()
898  set(LLVM_DEFINITIONS "${result}" PARENT_SCOPE)
899endfunction()
900get_compile_definitions()
901
902option(LLVM_FORCE_ENABLE_STATS "Enable statistics collection for builds that wouldn't normally enable it" OFF)
903