xref: /llvm-project/llvm/cmake/modules/HandleLLVMOptions.cmake (revision e1b5826c2b9dafbdf627b2abbf0157ae12306657)
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 "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE)
8
9include(CheckCompilerVersion)
10include(CheckProblematicConfigurations)
11include(HandleLLVMStdlib)
12include(CheckCCompilerFlag)
13include(CheckCSourceCompiles)
14include(CheckCXXCompilerFlag)
15include(CheckCXXSourceCompiles)
16include(CheckSymbolExists)
17include(CMakeDependentOption)
18include(LLVMProcessSources)
19
20if(CMAKE_LINKER MATCHES ".*lld" OR (LLVM_USE_LINKER STREQUAL "lld" OR LLVM_ENABLE_LLD))
21  set(LINKER_IS_LLD TRUE)
22else()
23  set(LINKER_IS_LLD FALSE)
24endif()
25
26if(CMAKE_LINKER MATCHES "lld-link" OR (MSVC AND (LLVM_USE_LINKER STREQUAL "lld" OR LLVM_ENABLE_LLD)))
27  set(LINKER_IS_LLD_LINK TRUE)
28else()
29  set(LINKER_IS_LLD_LINK FALSE)
30endif()
31
32set(LLVM_ENABLE_LTO OFF CACHE STRING "Build LLVM with LTO. May be specified as Thin or Full to use a particular kind of LTO")
33string(TOUPPER "${LLVM_ENABLE_LTO}" uppercase_LLVM_ENABLE_LTO)
34
35option(LLVM_ENABLE_FATLTO "Build LLVM with -ffat-lto-objects." OFF)
36
37# Ninja Job Pool support
38# The following only works with the Ninja generator in CMake >= 3.0.
39set(LLVM_PARALLEL_COMPILE_JOBS "" CACHE STRING
40  "Define the maximum number of concurrent compilation jobs (Ninja only).")
41if(LLVM_RAM_PER_COMPILE_JOB OR LLVM_RAM_PER_LINK_JOB OR LLVM_RAM_PER_TABLEGEN_JOB)
42  cmake_host_system_information(RESULT available_physical_memory QUERY AVAILABLE_PHYSICAL_MEMORY)
43  cmake_host_system_information(RESULT number_of_logical_cores QUERY NUMBER_OF_LOGICAL_CORES)
44endif()
45if(LLVM_RAM_PER_COMPILE_JOB)
46  math(EXPR jobs_with_sufficient_memory "${available_physical_memory} / ${LLVM_RAM_PER_COMPILE_JOB}" OUTPUT_FORMAT DECIMAL)
47  if (jobs_with_sufficient_memory LESS 1)
48    set(jobs_with_sufficient_memory 1)
49  endif()
50  if (jobs_with_sufficient_memory LESS number_of_logical_cores)
51    set(LLVM_PARALLEL_COMPILE_JOBS "${jobs_with_sufficient_memory}")
52  else()
53    set(LLVM_PARALLEL_COMPILE_JOBS "${number_of_logical_cores}")
54  endif()
55endif()
56if(LLVM_PARALLEL_COMPILE_JOBS)
57  if(NOT CMAKE_GENERATOR MATCHES "Ninja")
58    message(WARNING "Job pooling is only available with Ninja generators.")
59  else()
60    set_property(GLOBAL APPEND PROPERTY JOB_POOLS compile_job_pool=${LLVM_PARALLEL_COMPILE_JOBS})
61    set(CMAKE_JOB_POOL_COMPILE compile_job_pool)
62  endif()
63endif()
64
65set(LLVM_PARALLEL_LINK_JOBS "" CACHE STRING
66  "Define the maximum number of concurrent link jobs (Ninja only).")
67if(LLVM_RAM_PER_LINK_JOB)
68  math(EXPR jobs_with_sufficient_memory "${available_physical_memory} / ${LLVM_RAM_PER_LINK_JOB}" OUTPUT_FORMAT DECIMAL)
69  if (jobs_with_sufficient_memory LESS 1)
70    set(jobs_with_sufficient_memory 1)
71  endif()
72  if (jobs_with_sufficient_memory LESS number_of_logical_cores)
73    set(LLVM_PARALLEL_LINK_JOBS "${jobs_with_sufficient_memory}")
74  else()
75    set(LLVM_PARALLEL_LINK_JOBS "${number_of_logical_cores}")
76  endif()
77endif()
78if(CMAKE_GENERATOR MATCHES "Ninja")
79  if(NOT LLVM_PARALLEL_LINK_JOBS AND uppercase_LLVM_ENABLE_LTO STREQUAL "THIN")
80    message(STATUS "ThinLTO provides its own parallel linking - limiting parallel link jobs to 2.")
81    set(LLVM_PARALLEL_LINK_JOBS "2")
82  endif()
83  if(LLVM_PARALLEL_LINK_JOBS)
84    set_property(GLOBAL APPEND PROPERTY JOB_POOLS link_job_pool=${LLVM_PARALLEL_LINK_JOBS})
85    set(CMAKE_JOB_POOL_LINK link_job_pool)
86  endif()
87elseif(LLVM_PARALLEL_LINK_JOBS)
88  message(WARNING "Job pooling is only available with Ninja generators.")
89endif()
90
91set(LLVM_PARALLEL_TABLEGEN_JOBS "" CACHE STRING
92  "Define the maximum number of concurrent tablegen jobs (Ninja only).")
93if(LLVM_RAM_PER_TABLEGEN_JOB)
94  math(EXPR jobs_with_sufficient_memory "${available_physical_memory} / ${LLVM_RAM_PER_TABLEGEN_JOB}" OUTPUT_FORMAT DECIMAL)
95  if (jobs_with_sufficient_memory LESS 1)
96    set(jobs_with_sufficient_memory 1)
97  endif()
98  if (jobs_with_sufficient_memory LESS number_of_logical_cores)
99    set(LLVM_PARALLEL_TABLEGEN_JOBS "${jobs_with_sufficient_memory}")
100  else()
101    set(LLVM_PARALLEL_TABLEGEN_JOBS "${number_of_logical_cores}")
102  endif()
103endif()
104if(LLVM_PARALLEL_TABLEGEN_JOBS)
105  if(NOT CMAKE_GENERATOR MATCHES "Ninja")
106    message(WARNING "Job pooling is only available with Ninja generators.")
107  else()
108    set_property(GLOBAL APPEND PROPERTY JOB_POOLS tablegen_job_pool=${LLVM_PARALLEL_TABLEGEN_JOBS})
109    # Job pool for tablegen is set on the add_custom_command
110  endif()
111endif()
112
113if( LLVM_ENABLE_ASSERTIONS )
114  # MSVC doesn't like _DEBUG on release builds. See PR 4379.
115  if( NOT MSVC )
116    add_compile_definitions(_DEBUG)
117  endif()
118  # On non-Debug builds cmake automatically defines NDEBUG, so we
119  # explicitly undefine it:
120  if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )
121    add_compile_options($<$<OR:$<COMPILE_LANGUAGE:C>,$<COMPILE_LANGUAGE:CXX>>:-UNDEBUG>)
122    if (MSVC)
123      # Also remove /D NDEBUG to avoid MSVC warnings about conflicting defines.
124      foreach (flags_var_to_scrub
125          CMAKE_CXX_FLAGS_RELEASE
126          CMAKE_CXX_FLAGS_RELWITHDEBINFO
127          CMAKE_CXX_FLAGS_MINSIZEREL
128          CMAKE_C_FLAGS_RELEASE
129          CMAKE_C_FLAGS_RELWITHDEBINFO
130          CMAKE_C_FLAGS_MINSIZEREL)
131        string (REGEX REPLACE "(^| )[/-]D *NDEBUG($| )" " "
132          "${flags_var_to_scrub}" "${${flags_var_to_scrub}}")
133      endforeach()
134    endif()
135  endif()
136  # Enable assertions in libstdc++.
137  add_compile_definitions(_GLIBCXX_ASSERTIONS)
138  # Cautiously enable the extensive hardening mode in libc++.
139  if((DEFINED LIBCXX_HARDENING_MODE) AND
140     (NOT LIBCXX_HARDENING_MODE STREQUAL "extensive"))
141    message(WARNING "LLVM_ENABLE_ASSERTIONS implies LIBCXX_HARDENING_MODE \"extensive\" but is overriden from command line with value \"${LIBCXX_HARDENING_MODE}\".")
142  else()
143    set(LIBCXX_HARDENING_MODE "extensive")
144  endif()
145endif()
146
147# If we are targeting a GPU architecture in a runtimes build we want to ignore
148# all the standard flag handling.
149if(LLVM_RUNTIMES_GPU_BUILD)
150  return()
151endif()
152
153if(LLVM_ENABLE_EXPENSIVE_CHECKS)
154  # When LLVM_ENABLE_EXPENSIVE_CHECKS is ON, LLVM will intercept errors
155  # using assert(). An explicit check is performed here.
156  if (NOT LLVM_ENABLE_ASSERTIONS)
157    message(FATAL_ERROR "LLVM_ENABLE_EXPENSIVE_CHECKS requires LLVM_ENABLE_ASSERTIONS \"ON\".")
158  endif()
159  add_compile_definitions(EXPENSIVE_CHECKS)
160
161  # In libstdc++ 9 and earlier, std::min_element is not constexpr when
162  # _GLIBCXX_DEBUG is enabled.
163  CHECK_CXX_SOURCE_COMPILES("
164    #define _GLIBCXX_DEBUG
165    #include <algorithm>
166    int main(int argc, char** argv) {
167      static constexpr int data[] = {0, 1};
168      constexpr const int* min_elt = std::min_element(&data[0], &data[2]);
169      return 0;
170    }" CXX_SUPPORTS_GLIBCXX_DEBUG)
171  if(CXX_SUPPORTS_GLIBCXX_DEBUG)
172    add_compile_definitions(_GLIBCXX_DEBUG)
173  else()
174    add_compile_definitions(_GLIBCXX_ASSERTIONS)
175  endif()
176endif()
177
178if (LLVM_ENABLE_STRICT_FIXED_SIZE_VECTORS)
179  add_compile_definitions(STRICT_FIXED_SIZE_VECTORS)
180endif()
181
182string(TOUPPER "${LLVM_ABI_BREAKING_CHECKS}" uppercase_LLVM_ABI_BREAKING_CHECKS)
183
184if( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "WITH_ASSERTS" )
185  if( LLVM_ENABLE_ASSERTIONS )
186    set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 )
187  endif()
188elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_ON" )
189  set( LLVM_ENABLE_ABI_BREAKING_CHECKS 1 )
190elseif( uppercase_LLVM_ABI_BREAKING_CHECKS STREQUAL "FORCE_OFF" )
191  # We don't need to do anything special to turn off ABI breaking checks.
192elseif( NOT DEFINED LLVM_ABI_BREAKING_CHECKS )
193  # Treat LLVM_ABI_BREAKING_CHECKS like "FORCE_OFF" when it has not been
194  # defined.
195else()
196  message(FATAL_ERROR "Unknown value for LLVM_ABI_BREAKING_CHECKS: \"${LLVM_ABI_BREAKING_CHECKS}\"!")
197endif()
198
199string(TOUPPER "${LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING}" uppercase_LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING)
200
201if( uppercase_LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING STREQUAL "COVERAGE" )
202  set( ENABLE_DEBUGLOC_COVERAGE_TRACKING 1 )
203elseif( uppercase_LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING STREQUAL "DISABLED" OR NOT DEFINED LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING )
204  # The DISABLED setting is default and requires no additional defines.
205else()
206  message(FATAL_ERROR "Unknown value for LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING: \"${LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING}\"!")
207endif()
208
209if( LLVM_REVERSE_ITERATION )
210  set( LLVM_ENABLE_REVERSE_ITERATION 1 )
211endif()
212
213if(WIN32)
214  set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
215  if(CYGWIN)
216    set(LLVM_ON_WIN32 0)
217    set(LLVM_ON_UNIX 1)
218  else(CYGWIN)
219    set(LLVM_ON_WIN32 1)
220    set(LLVM_ON_UNIX 0)
221  endif(CYGWIN)
222elseif(FUCHSIA OR UNIX)
223  set(LLVM_ON_WIN32 0)
224  set(LLVM_ON_UNIX 1)
225  if(APPLE OR ${CMAKE_SYSTEM_NAME} MATCHES "AIX")
226    set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
227  else()
228    set(LLVM_HAVE_LINK_VERSION_SCRIPT 1)
229  endif()
230elseif(CMAKE_SYSTEM_NAME STREQUAL "Generic")
231  set(LLVM_ON_WIN32 0)
232  set(LLVM_ON_UNIX 0)
233  set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
234else()
235  MESSAGE(SEND_ERROR "Unable to determine platform")
236endif()
237
238if (CMAKE_SYSTEM_NAME MATCHES "OS390")
239  set(LLVM_HAVE_LINK_VERSION_SCRIPT 0)
240endif()
241
242set(EXEEXT ${CMAKE_EXECUTABLE_SUFFIX})
243set(LTDL_SHLIB_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
244
245# We use *.dylib rather than *.so on darwin, but we stick with *.so on AIX.
246if(${CMAKE_SYSTEM_NAME} MATCHES "AIX")
247  set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_MODULE_SUFFIX})
248else()
249  set(LLVM_PLUGIN_EXT ${CMAKE_SHARED_LIBRARY_SUFFIX})
250endif()
251
252if(APPLE)
253  # Darwin-specific linker flags for loadable modules.
254  set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-flat_namespace -Wl,-undefined -Wl,dynamic_lookup")
255endif()
256
257if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
258  # RHEL7 has ar and ranlib being non-deterministic by default. The D flag forces determinism,
259  # however only GNU version of ar and ranlib (2.27) have this option.
260  # RHEL DTS7 is also affected by this, which uses GNU binutils 2.28
261  execute_process(COMMAND ${CMAKE_AR} rD t.a
262                  WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
263                  RESULT_VARIABLE AR_RESULT
264                  OUTPUT_QUIET
265                  ERROR_QUIET
266                  )
267  if(${AR_RESULT} EQUAL 0)
268    execute_process(COMMAND ${CMAKE_RANLIB} -D t.a
269                    WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
270                    RESULT_VARIABLE RANLIB_RESULT
271                    OUTPUT_QUIET
272                    ERROR_QUIET
273                    )
274    if(${RANLIB_RESULT} EQUAL 0)
275      set(CMAKE_C_ARCHIVE_CREATE "<CMAKE_AR> Dqc <TARGET> <LINK_FLAGS> <OBJECTS>"
276          CACHE STRING "archive create command")
277      set(CMAKE_C_ARCHIVE_APPEND "<CMAKE_AR> Dq  <TARGET> <LINK_FLAGS> <OBJECTS>")
278      set(CMAKE_C_ARCHIVE_FINISH "<CMAKE_RANLIB> -D <TARGET>" CACHE STRING "ranlib command")
279
280      set(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> Dqc <TARGET> <LINK_FLAGS> <OBJECTS>"
281          CACHE STRING "archive create command")
282      set(CMAKE_CXX_ARCHIVE_APPEND "<CMAKE_AR> Dq  <TARGET> <LINK_FLAGS> <OBJECTS>")
283      set(CMAKE_CXX_ARCHIVE_FINISH "<CMAKE_RANLIB> -D <TARGET>" CACHE STRING "ranlib command")
284    endif()
285    file(REMOVE ${CMAKE_BINARY_DIR}/t.a)
286  endif()
287endif()
288
289if(${CMAKE_SYSTEM_NAME} MATCHES "AIX")
290  # -fPIC does not enable the large code model for GCC on AIX but does for XL.
291  if(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
292    append("-mcmodel=large" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
293    append("-Wl,-bglink=large"
294        CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
295  elseif(CMAKE_CXX_COMPILER_ID MATCHES "XL")
296    # XL generates a small number of relocations not of the large model, -bbigtoc is needed.
297    append("-Wl,-bbigtoc"
298           CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
299    # The default behaviour on AIX processes dynamic initialization of non-local variables with
300    # static storage duration even for archive members that are otherwise unreferenced.
301    # Since `--whole-archive` is not used by the LLVM build to keep such initializations for Linux,
302    # we can limit the processing for archive members to only those that are otherwise referenced.
303    append("-bcdtors:mbr"
304           CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
305  endif()
306  if(BUILD_SHARED_LIBS)
307    # See rpath handling in AddLLVM.cmake
308    # FIXME: Remove this warning if this rpath is no longer hardcoded.
309    message(WARNING "Build and install environment path info may be exposed; binaries will also be unrelocatable.")
310  endif()
311endif()
312
313# Pass -Wl,-z,defs. This makes sure all symbols are defined. Otherwise a DSO
314# build might work on ELF but fail on MachO/COFF.
315if(NOT (CMAKE_SYSTEM_NAME MATCHES "Darwin|FreeBSD|OpenBSD|DragonFly|AIX|OS390|Emscripten" OR
316        WIN32 OR CYGWIN) AND
317   NOT LLVM_USE_SANITIZER)
318  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,defs")
319endif()
320
321# Pass -Wl,-z,nodelete. This makes sure our shared libraries are not unloaded
322# by dlclose(). We need that since the CLI API relies on cross-references
323# between global objects which became horribly broken when one of the libraries
324# is unloaded.
325if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
326  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,nodelete")
327  set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -Wl,-z,nodelete")
328endif()
329
330
331function(append value)
332  foreach(variable ${ARGN})
333    set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
334  endforeach(variable)
335endfunction()
336
337function(prepend value)
338  foreach(variable ${ARGN})
339    set(${variable} "${value} ${${variable}}" PARENT_SCOPE)
340  endforeach(variable)
341endfunction()
342
343function(append_if condition value)
344  if (${condition})
345    foreach(variable ${ARGN})
346      set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
347    endforeach(variable)
348  endif()
349endfunction()
350
351macro(add_flag_if_supported flag name)
352  check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}")
353  append_if("C_SUPPORTS_${name}" "${flag}" CMAKE_C_FLAGS)
354  check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}")
355  append_if("CXX_SUPPORTS_${name}" "${flag}" CMAKE_CXX_FLAGS)
356endmacro()
357
358function(add_flag_or_print_warning flag name)
359  check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}")
360  check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}")
361  if (C_SUPPORTS_${name} AND CXX_SUPPORTS_${name})
362    message(STATUS "Building with ${flag}")
363    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${flag}" PARENT_SCOPE)
364    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE)
365    set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${flag}" PARENT_SCOPE)
366  else()
367    message(WARNING "${flag} is not supported.")
368  endif()
369endfunction()
370
371function(has_msvc_incremental_no_flag flags incr_no_flag_on)
372  set(${incr_no_flag_on} OFF PARENT_SCOPE)
373  string(FIND "${flags}" "/INCREMENTAL" idx REVERSE)
374  if (${idx} GREATER -1)
375    string(SUBSTRING "${flags}" ${idx} 15 no_flag)
376    if (${no_flag} MATCHES "/INCREMENTAL:NO")
377      set(${incr_no_flag_on} ON PARENT_SCOPE)
378    endif()
379  endif()
380endfunction()
381
382if( LLVM_ENABLE_LLD )
383  if ( LLVM_USE_LINKER )
384    message(FATAL_ERROR "LLVM_ENABLE_LLD and LLVM_USE_LINKER can't be set at the same time")
385  endif()
386
387  # In case of MSVC cmake always invokes the linker directly, so the linker
388  # should be specified by CMAKE_LINKER cmake variable instead of by -fuse-ld
389  # compiler option.
390  if ( MSVC )
391    if(NOT CMAKE_LINKER MATCHES "lld-link")
392      get_filename_component(CXX_COMPILER_DIR ${CMAKE_CXX_COMPILER} DIRECTORY)
393      get_filename_component(C_COMPILER_DIR ${CMAKE_C_COMPILER} DIRECTORY)
394      find_program(LLD_LINK NAMES "lld-link" "lld-link.exe" HINTS ${CXX_COMPILER_DIR} ${C_COMPILER_DIR} DOC "lld linker")
395      if(NOT LLD_LINK)
396        message(FATAL_ERROR
397          "LLVM_ENABLE_LLD set, but cannot find lld-link. "
398          "Consider setting CMAKE_LINKER to lld-link path.")
399      endif()
400      set(CMAKE_LINKER ${LLD_LINK})
401    endif()
402  else()
403    set(LLVM_USE_LINKER "lld")
404  endif()
405endif()
406
407if( LLVM_USE_LINKER )
408  append("-fuse-ld=${LLVM_USE_LINKER}"
409    CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
410  check_cxx_source_compiles("int main() { return 0; }" CXX_SUPPORTS_CUSTOM_LINKER)
411  if ( NOT CXX_SUPPORTS_CUSTOM_LINKER )
412    message(FATAL_ERROR "Host compiler does not support '-fuse-ld=${LLVM_USE_LINKER}'. "
413                        "Please make sure that '${LLVM_USE_LINKER}' is installed and "
414                        "that your host compiler can compile a simple program when "
415                        "given the option '-fuse-ld=${LLVM_USE_LINKER}'.")
416  endif()
417endif()
418
419if( LLVM_ENABLE_PIC )
420  if( XCODE )
421    # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
422    # know how to disable this, so just force ENABLE_PIC off for now.
423    message(WARNING "-fPIC not supported with Xcode.")
424  elseif( WIN32 OR CYGWIN)
425    # On Windows all code is PIC. MinGW warns if -fPIC is used.
426  else()
427    add_flag_or_print_warning("-fPIC" FPIC)
428    # Enable interprocedural optimizations for non-inline functions which would
429    # otherwise be disabled due to GCC -fPIC's default.
430    # Note: GCC<10.3 has a bug on SystemZ.
431    #
432    # Note: Clang allows IPO for -fPIC so this optimization is less effective.
433    # Clang 13 has a bug related to -fsanitize-coverage
434    # -fno-semantic-interposition (https://reviews.llvm.org/D117183).
435    if ((CMAKE_COMPILER_IS_GNUCXX AND
436         NOT (LLVM_NATIVE_ARCH STREQUAL "SystemZ" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 10.3))
437       OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND CMAKE_CXX_COMPILER_VERSION GREATER_EQUAL 14))
438      add_flag_if_supported("-fno-semantic-interposition" FNO_SEMANTIC_INTERPOSITION)
439    endif()
440  endif()
441  # GCC for MIPS can miscompile LLVM due to PR37701.
442  if(CMAKE_COMPILER_IS_GNUCXX AND LLVM_NATIVE_ARCH STREQUAL "Mips" AND
443         NOT Uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
444    append("-fno-shrink-wrap" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
445  endif()
446  # gcc with -O3 -fPIC generates TLS sequences that violate the spec on
447  # Solaris/sparcv9, causing executables created with the system linker
448  # to SEGV (GCC PR target/96607).
449  # clang with -O3 -fPIC generates code that SEGVs.
450  # Both can be worked around by compiling with -O instead.
451  if(${CMAKE_SYSTEM_NAME} STREQUAL "SunOS" AND LLVM_NATIVE_ARCH STREQUAL "Sparc")
452    llvm_replace_compiler_option(CMAKE_CXX_FLAGS_RELEASE "-O[23]" "-O")
453    llvm_replace_compiler_option(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O[23]" "-O")
454  endif()
455endif()
456
457if((NOT (${CMAKE_SYSTEM_NAME} MATCHES "AIX")) AND
458   (NOT (WIN32 OR CYGWIN) OR (MINGW AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")))
459  # GCC for MinGW does nothing about -fvisibility-inlines-hidden, but warns
460  # about use of the attributes. As long as we don't use the attributes (to
461  # override the default) we shouldn't set the command line options either.
462  # GCC on AIX warns if -fvisibility-inlines-hidden is used and Clang on AIX doesn't currently support visibility.
463  check_cxx_compiler_flag("-fvisibility-inlines-hidden" SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG)
464  append_if(SUPPORTS_FVISIBILITY_INLINES_HIDDEN_FLAG "-fvisibility-inlines-hidden" CMAKE_CXX_FLAGS)
465endif()
466
467if(CMAKE_SIZEOF_VOID_P EQUAL 8 AND MINGW)
468  add_compile_definitions(_FILE_OFFSET_BITS=64)
469endif()
470
471if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
472  # TODO: support other platforms and toolchains.
473  if( LLVM_BUILD_32_BITS )
474    message(STATUS "Building 32 bits executables and libraries.")
475    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -m32")
476    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -m32")
477    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32")
478    set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -m32")
479    set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} -m32")
480
481    # FIXME: CMAKE_SIZEOF_VOID_P is still 8
482    add_compile_definitions(_LARGEFILE_SOURCE)
483    add_compile_definitions(_FILE_OFFSET_BITS=64)
484  endif( LLVM_BUILD_32_BITS )
485endif( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
486
487# If building on a GNU specific 32-bit system, make sure off_t is 64 bits
488# so that off_t can stored offset > 2GB.
489# Android until version N (API 24) doesn't support it.
490if (ANDROID AND (ANDROID_NATIVE_API_LEVEL LESS 24))
491  set(LLVM_FORCE_SMALLFILE_FOR_ANDROID TRUE)
492endif()
493if( CMAKE_SIZEOF_VOID_P EQUAL 4 AND NOT LLVM_FORCE_SMALLFILE_FOR_ANDROID)
494  # FIXME: It isn't handled in LLVM_BUILD_32_BITS.
495  add_compile_definitions(_LARGEFILE_SOURCE)
496  add_compile_definitions(_FILE_OFFSET_BITS=64)
497endif()
498
499if( XCODE )
500  # For Xcode enable several build settings that correspond to
501  # many warnings that are on by default in Clang but are
502  # not enabled for historical reasons.  For versions of Xcode
503  # that do not support these options they will simply
504  # be ignored.
505  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_RETURN_TYPE "YES")
506  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_ABOUT_MISSING_NEWLINE "YES")
507  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VALUE "YES")
508  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_VARIABLE "YES")
509  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_SIGN_COMPARE "YES")
510  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNUSED_FUNCTION "YES")
511  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_INITIALIZER_NOT_FULLY_BRACKETED "YES")
512  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_HIDDEN_VIRTUAL_FUNCTIONS "YES")
513  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_UNINITIALIZED_AUTOS "YES")
514  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_BOOL_CONVERSION "YES")
515  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_EMPTY_BODY "YES")
516  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_ENUM_CONVERSION "YES")
517  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_INT_CONVERSION "YES")
518  set(CMAKE_XCODE_ATTRIBUTE_CLANG_WARN_CONSTANT_CONVERSION "YES")
519  set(CMAKE_XCODE_ATTRIBUTE_GCC_WARN_NON_VIRTUAL_DESTRUCTOR "YES")
520endif()
521
522# On Win32 using MS tools, provide an option to set the number of parallel jobs
523# to use.
524if( MSVC_IDE )
525  set(LLVM_COMPILER_JOBS "0" CACHE STRING
526    "Number of parallel compiler jobs. 0 means use all processors. Default is 0.")
527  if( NOT LLVM_COMPILER_JOBS STREQUAL "1" )
528    if( LLVM_COMPILER_JOBS STREQUAL "0" )
529      add_compile_options(/MP)
530    else()
531      message(STATUS "Number of parallel compiler jobs set to " ${LLVM_COMPILER_JOBS})
532      add_compile_options(/MP${LLVM_COMPILER_JOBS})
533    endif()
534  else()
535    message(STATUS "Parallel compilation disabled")
536  endif()
537endif()
538
539# set stack reserved size to ~10MB
540if(MSVC)
541  # CMake previously automatically set this value for MSVC builds, but the
542  # behavior was changed in CMake 2.8.11 (Issue 12437) to use the MSVC default
543  # value (1 MB) which is not enough for us in tasks such as parsing recursive
544  # C++ templates in Clang.
545  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${CMAKE_CXX_LINKER_WRAPPER_FLAG}/STACK:10000000")
546elseif(MINGW OR CYGWIN)
547  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--stack,16777216")
548
549  # Pass -mbig-obj to mingw gas to avoid COFF 2**16 section limit.
550  if (NOT CMAKE_CXX_COMPILER_ID MATCHES "Clang")
551    append("-Wa,-mbig-obj" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
552  endif()
553endif()
554
555option(LLVM_ENABLE_WARNINGS "Enable compiler warnings." ON)
556
557if( MSVC )
558
559  # Add definitions that make MSVC much less annoying.
560  add_compile_definitions(
561    # For some reason MS wants to deprecate a bunch of standard functions...
562    _CRT_SECURE_NO_DEPRECATE
563    _CRT_SECURE_NO_WARNINGS
564    _CRT_NONSTDC_NO_DEPRECATE
565    _CRT_NONSTDC_NO_WARNINGS
566    _SCL_SECURE_NO_DEPRECATE
567    _SCL_SECURE_NO_WARNINGS
568    )
569
570  # Tell MSVC to use the Unicode version of the Win32 APIs instead of ANSI.
571  add_compile_definitions(
572    UNICODE
573    _UNICODE
574  )
575
576  if (LLVM_WINSYSROOT)
577    if (NOT CLANG_CL)
578      message(ERROR "LLVM_WINSYSROOT requires clang-cl")
579    endif()
580    append("/winsysroot${LLVM_WINSYSROOT}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
581    if (LINKER_IS_LLD_LINK)
582      append("/winsysroot:${LLVM_WINSYSROOT}"
583          CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS
584          CMAKE_SHARED_LINKER_FLAGS)
585    endif()
586  endif()
587
588  if (LLVM_ENABLE_WERROR)
589    append("/WX" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
590  endif (LLVM_ENABLE_WERROR)
591
592  append("/Zc:inline" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
593
594  if (CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
595    # Enable standards-conforming preprocessor.
596    # https://learn.microsoft.com/en-us/cpp/build/reference/zc-preprocessor
597    append("/Zc:preprocessor" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
598  endif ()
599
600  # Some projects use the __cplusplus preprocessor macro to check support for
601  # a particular version of the C++ standard. When this option is not specified
602  # explicitly, macro's value is "199711L" that implies C++98 Standard.
603  # https://devblogs.microsoft.com/cppblog/msvc-now-correctly-reports-__cplusplus/
604  append("/Zc:__cplusplus" CMAKE_CXX_FLAGS)
605
606  # Allow users to request PDBs in release mode. CMake offeres the
607  # RelWithDebInfo configuration, but it uses different optimization settings
608  # (/Ob1 vs /Ob2 or -O2 vs -O3). LLVM provides this flag so that users can get
609  # PDBs without changing codegen.
610  option(LLVM_ENABLE_PDB OFF)
611  if (LLVM_ENABLE_PDB AND uppercase_CMAKE_BUILD_TYPE STREQUAL "RELEASE")
612    append("/Zi" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
613    # /DEBUG disables linker GC and ICF, but we want those in Release mode.
614    append("/DEBUG /OPT:REF /OPT:ICF"
615          CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS
616          CMAKE_SHARED_LINKER_FLAGS)
617  endif()
618
619  # Get all linker flags in upper case form so we can search them.
620  string(CONCAT all_linker_flags_uppercase
621     ${CMAKE_EXE_LINKER_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} " "
622     ${CMAKE_EXE_LINKER_FLAGS} " "
623     ${CMAKE_MODULE_LINKER_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} " "
624     ${CMAKE_MODULE_LINKER_FLAGS} " "
625     ${CMAKE_SHARED_LINKER_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} " "
626     ${CMAKE_SHARED_LINKER_FLAGS})
627  string(TOUPPER "${all_linker_flags_uppercase}" all_linker_flags_uppercase)
628
629  if (CLANG_CL AND LINKER_IS_LLD)
630    # If we are using clang-cl with lld-link and /debug is present in any of the
631    # linker flag variables, pass -gcodeview-ghash to the compiler to speed up
632    # linking. This flag is orthogonal from /Zi, /Z7, and other flags that
633    # enable debug info emission, and only has an effect if those are also in
634    # use.
635    string(FIND "${all_linker_flags_uppercase}" "/DEBUG" linker_flag_idx)
636    if (${linker_flag_idx} GREATER -1)
637      add_flag_if_supported("-gcodeview-ghash" GCODEVIEW_GHASH)
638    endif()
639  endif()
640
641  # "Generate Intrinsic Functions".
642  append("/Oi" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
643
644  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT LLVM_ENABLE_LTO)
645    # clang-cl and cl by default produce non-deterministic binaries because
646    # link.exe /incremental requires a timestamp in the .obj file.  clang-cl
647    # has the flag /Brepro to force deterministic binaries. We want to pass that
648    # whenever you're building with clang unless you're passing /incremental
649    # or using LTO (/Brepro with LTO would result in a warning about the flag
650    # being unused, because we're not generating object files).
651    # This checks CMAKE_CXX_COMPILER_ID in addition to check_cxx_compiler_flag()
652    # because cl.exe does not emit an error on flags it doesn't understand,
653    # letting check_cxx_compiler_flag() claim it understands all flags.
654
655    # Check if /INCREMENTAL is passed to the linker and complain that it
656    # won't work with /Brepro.
657    has_msvc_incremental_no_flag("${CMAKE_EXE_LINKER_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} ${CMAKE_EXE_LINKER_FLAGS}" NO_INCR_EXE)
658    has_msvc_incremental_no_flag("${CMAKE_MODULE_LINKER_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} ${CMAKE_MODULE_LINKER_FLAGS}" NO_INCR_MODULE)
659    has_msvc_incremental_no_flag("${CMAKE_SHARED_LINKER_FLAGS_${uppercase_CMAKE_BUILD_TYPE}} ${CMAKE_SHARED_LINKER_FLAGS}" NO_INCR_SHARED)
660    if (NO_INCR_EXE AND NO_INCR_MODULE AND NO_INCR_SHARED)
661      append("/Brepro" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
662    else()
663      message(WARNING "/Brepro not compatible with /INCREMENTAL linking - builds will be non-deterministic")
664    endif()
665  endif()
666  # By default MSVC has a 2^16 limit on the number of sections in an object file,
667  # but in many objects files need more than that. This flag is to increase the
668  # number of sections.
669  append("/bigobj" CMAKE_CXX_FLAGS)
670
671  # Enable standards conformance mode.
672  # This ensures handling of various C/C++ constructs is more similar to other compilers.
673  append("/permissive-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
674endif( MSVC )
675
676# Warnings-as-errors handling for GCC-compatible compilers:
677if ( LLVM_COMPILER_IS_GCC_COMPATIBLE )
678  append_if(LLVM_ENABLE_WERROR "-Werror" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
679  append_if(LLVM_ENABLE_WERROR "-Wno-error" CMAKE_REQUIRED_FLAGS)
680endif( LLVM_COMPILER_IS_GCC_COMPATIBLE )
681
682# Specific default warnings-as-errors for compilers accepting GCC-compatible warning flags:
683if ( LLVM_COMPILER_IS_GCC_COMPATIBLE OR CMAKE_CXX_COMPILER_ID MATCHES "XL" )
684  append("-Werror=date-time" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
685endif( LLVM_COMPILER_IS_GCC_COMPATIBLE OR CMAKE_CXX_COMPILER_ID MATCHES "XL" )
686
687if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
688  append("-Werror=unguarded-availability-new" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
689endif()
690
691if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
692  # LLVM data structures like llvm::User and llvm::MDNode rely on
693  # the value of object storage persisting beyond the lifetime of the
694  # object (#24952).  This is not standard compliant and causes a runtime
695  # crash if LLVM is built with GCC and LTO enabled (#57740).  Until
696  # these bugs are fixed, we need to disable dead store eliminations
697  # based on object lifetime.
698  append("-fno-lifetime-dse" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
699endif ()
700
701# Modules enablement for GCC-compatible compilers:
702if ( LLVM_COMPILER_IS_GCC_COMPATIBLE AND LLVM_ENABLE_MODULES )
703  set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
704  set(module_flags "-fmodules -fmodules-cache-path=${PROJECT_BINARY_DIR}/module.cache")
705  if (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
706    # On Darwin -fmodules does not imply -fcxx-modules.
707    set(module_flags "${module_flags} -fcxx-modules")
708  endif()
709  if (LLVM_ENABLE_LOCAL_SUBMODULE_VISIBILITY)
710    set(module_flags "${module_flags} -Xclang -fmodules-local-submodule-visibility")
711  endif()
712  if (LLVM_ENABLE_MODULE_DEBUGGING AND
713      ((uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") OR
714       (uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")))
715    set(module_flags "${module_flags} -gmodules")
716  endif()
717  append("${module_flags}" CMAKE_CXX_FLAGS)
718endif( LLVM_COMPILER_IS_GCC_COMPATIBLE AND LLVM_ENABLE_MODULES )
719
720if (MSVC)
721  if (NOT CLANG_CL)
722    set(msvc_warning_flags
723      # Disabled warnings.
724      -wd4141 # Suppress ''modifier' : used more than once' (because of __forceinline combined with inline)
725      -wd4146 # Suppress 'unary minus operator applied to unsigned type, result still unsigned'
726      -wd4244 # Suppress ''argument' : conversion from 'type1' to 'type2', possible loss of data'
727      -wd4267 # Suppress ''var' : conversion from 'size_t' to 'type', possible loss of data'
728      -wd4291 # Suppress ''declaration' : no matching operator delete found; memory will not be freed if initialization throws an exception'
729      -wd4351 # Suppress 'new behavior: elements of array 'array' will be default initialized'
730      -wd4456 # Suppress 'declaration of 'var' hides local variable'
731      -wd4457 # Suppress 'declaration of 'var' hides function parameter'
732      -wd4458 # Suppress 'declaration of 'var' hides class member'
733      -wd4459 # Suppress 'declaration of 'var' hides global declaration'
734      -wd4503 # Suppress ''identifier' : decorated name length exceeded, name was truncated'
735      -wd4624 # Suppress ''derived class' : destructor could not be generated because a base class destructor is inaccessible'
736      -wd4722 # Suppress 'function' : destructor never returns, potential memory leak
737      -wd4100 # Suppress 'unreferenced formal parameter'
738      -wd4127 # Suppress 'conditional expression is constant'
739      -wd4512 # Suppress 'assignment operator could not be generated'
740      -wd4505 # Suppress 'unreferenced local function has been removed'
741      -wd4610 # Suppress '<class> can never be instantiated'
742      -wd4510 # Suppress 'default constructor could not be generated'
743      -wd4702 # Suppress 'unreachable code'
744      -wd4245 # Suppress ''conversion' : conversion from 'type1' to 'type2', signed/unsigned mismatch'
745      -wd4706 # Suppress 'assignment within conditional expression'
746      -wd4310 # Suppress 'cast truncates constant value'
747      -wd4701 # Suppress 'potentially uninitialized local variable'
748      -wd4703 # Suppress 'potentially uninitialized local pointer variable'
749      -wd4389 # Suppress 'signed/unsigned mismatch'
750      -wd4611 # Suppress 'interaction between '_setjmp' and C++ object destruction is non-portable'
751      -wd4805 # Suppress 'unsafe mix of type <type> and type <type> in operation'
752      -wd4204 # Suppress 'nonstandard extension used : non-constant aggregate initializer'
753      -wd4577 # Suppress 'noexcept used with no exception handling mode specified; termination on exception is not guaranteed'
754      -wd4091 # Suppress 'typedef: ignored on left of '' when no variable is declared'
755          # C4592 is disabled because of false positives in Visual Studio 2015
756          # Update 1. Re-evaluate the usefulness of this diagnostic with Update 2.
757      -wd4592 # Suppress ''var': symbol will be dynamically initialized (implementation limitation)
758      -wd4319 # Suppress ''operator' : zero extending 'type' to 'type' of greater size'
759          # C4709 is disabled because of a bug with Visual Studio 2017 as of
760          # v15.8.8. Re-evaluate the usefulness of this diagnostic when the bug
761          # is fixed.
762      -wd4709 # Suppress comma operator within array index expression
763
764      # We'd like this warning to be enabled, but it triggers from code in
765      # WinBase.h that we don't have control over.
766      -wd5105 # Suppress macro expansion producing 'defined' has undefined behavior
767
768      # Ideally, we'd like this warning to be enabled, but even MSVC 2019 doesn't
769      # support the 'aligned' attribute in the way that clang sources requires (for
770      # any code that uses the LLVM_ALIGNAS macro), so this is must be disabled to
771      # avoid unwanted alignment warnings.
772      -wd4324 # Suppress 'structure was padded due to __declspec(align())'
773      # This is triggered for every variable that is a template type of a class even
774      # if there private when the class is dllexport'ed
775      -wd4251 # Suppress 'needs to have dll-interface to be used by clients'
776      # We only putting dll export on classes with out of line members so this
777      # warning gets triggered a lot for bases we haven't exported'
778      -wd4275 # non dll-interface class used as base for dll-interface class
779
780      # Promoted warnings.
781      -w14062 # Promote 'enumerator in switch of enum is not handled' to level 1 warning.
782
783      # Promoted warnings to errors.
784      -we4238 # Promote 'nonstandard extension used : class rvalue used as lvalue' to error.
785      )
786  endif(NOT CLANG_CL)
787
788  # Enable warnings
789  if (LLVM_ENABLE_WARNINGS)
790    # Put /W4 in front of all the -we flags. cl.exe doesn't care, but for
791    # clang-cl having /W4 after the -we flags will re-enable the warnings
792    # disabled by -we.
793    set(msvc_warning_flags "/W4 ${msvc_warning_flags}")
794    # CMake appends /W3 by default, and having /W3 followed by /W4 will result in
795    # cl : Command line warning D9025 : overriding '/W3' with '/W4'.  Since this is
796    # a command line warning and not a compiler warning, it cannot be suppressed except
797    # by fixing the command line.
798    string(REGEX REPLACE " /W[0-4]" "" CMAKE_C_FLAGS "${CMAKE_C_FLAGS}")
799    string(REGEX REPLACE " /W[0-4]" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
800
801    if (LLVM_ENABLE_PEDANTIC)
802      # No MSVC equivalent available
803    endif (LLVM_ENABLE_PEDANTIC)
804  endif (LLVM_ENABLE_WARNINGS)
805
806  foreach(flag ${msvc_warning_flags})
807    append("${flag}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
808  endforeach(flag)
809endif (MSVC)
810
811if (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
812
813  # Don't add -Wall for clang-cl, because it maps -Wall to -Weverything for
814  # MSVC compatibility.  /W4 is added above instead.
815  if (NOT CLANG_CL)
816    append("-Wall" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
817  endif()
818
819  append("-Wextra -Wno-unused-parameter -Wwrite-strings" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
820  append("-Wcast-qual" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
821
822  # Turn off missing field initializer warnings for gcc to avoid noise from
823  # false positives with empty {}. Turn them on otherwise (they're off by
824  # default for clang).
825  if (CMAKE_COMPILER_IS_GNUCXX)
826    append("-Wno-missing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
827  else()
828    append("-Wmissing-field-initializers" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
829  endif()
830
831  if (LLVM_ENABLE_PEDANTIC AND LLVM_COMPILER_IS_GCC_COMPATIBLE)
832    append("-pedantic" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
833    append("-Wno-long-long" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
834
835    # GCC warns about redundant toplevel semicolons (enabled by -pedantic
836    # above), while Clang doesn't. Enable the corresponding Clang option to
837    # pick up on these even in builds with Clang.
838    add_flag_if_supported("-Wc++98-compat-extra-semi" CXX98_COMPAT_EXTRA_SEMI_FLAG)
839  endif()
840
841  append("-Wimplicit-fallthrough" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
842
843  set(CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG 0)
844  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
845    set(CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG 1)
846    append("-Wcovered-switch-default" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
847  endif()
848  append_if(USE_NO_UNINITIALIZED "-Wno-uninitialized" CMAKE_CXX_FLAGS)
849  append_if(USE_NO_MAYBE_UNINITIALIZED "-Wno-maybe-uninitialized" CMAKE_CXX_FLAGS)
850
851  # Disable -Wnonnull for GCC warning as it is emitting a lot of false positives.
852  if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
853    append("-Wno-nonnull" CMAKE_CXX_FLAGS)
854  endif()
855
856  # Disable -Wclass-memaccess, a C++-only warning from GCC 8 that fires on
857  # LLVM's ADT classes.
858  if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
859    if (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 8.1)
860      append("-Wno-class-memaccess" CMAKE_CXX_FLAGS)
861    endif()
862  endif()
863
864  # Disable -Wredundant-move and -Wpessimizing-move on GCC>=9. GCC wants to
865  # remove std::move in code like
866  # "A foo(ConvertibleToA a) { return std::move(a); }",
867  # but this code does not compile (or uses the copy
868  # constructor instead) on clang<=3.8. Clang also has a -Wredundant-move and
869  # -Wpessimizing-move, but they only fire when the types match exactly, so we
870  # can keep them here.
871  if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
872    if (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 9.1)
873      append("-Wno-redundant-move" CMAKE_CXX_FLAGS)
874      append("-Wno-pessimizing-move" CMAKE_CXX_FLAGS)
875    endif()
876  endif()
877
878  # The LLVM libraries have no stable C++ API, so -Wnoexcept-type is not useful.
879  append("-Wno-noexcept-type" CMAKE_CXX_FLAGS)
880
881  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
882    append("-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
883  endif()
884  append("-Wdelete-non-virtual-dtor" CMAKE_CXX_FLAGS)
885
886  # Enable -Wsuggest-override if it's available, and only if it doesn't
887  # suggest adding 'override' to functions that are already marked 'final'
888  # (which means it is disabled for GCC < 9.2).
889  check_cxx_compiler_flag("-Wsuggest-override" CXX_SUPPORTS_SUGGEST_OVERRIDE_FLAG)
890  if (CXX_SUPPORTS_SUGGEST_OVERRIDE_FLAG)
891    set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
892    set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror=suggest-override")
893    CHECK_CXX_SOURCE_COMPILES("class base {public: virtual void anchor();};
894                               class derived : base {public: void anchor() final;};
895                               int main() { return 0; }"
896                              CXX_WSUGGEST_OVERRIDE_ALLOWS_ONLY_FINAL)
897    set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
898    append_if(CXX_WSUGGEST_OVERRIDE_ALLOWS_ONLY_FINAL "-Wsuggest-override" CMAKE_CXX_FLAGS)
899  endif()
900
901  # Check if -Wcomment is OK with an // comment ending with '\' if the next
902  # line is also a // comment.
903  set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
904  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror -Wcomment")
905  CHECK_C_SOURCE_COMPILES("// \\\\\\n//\\nint main(void) {return 0;}"
906                          C_WCOMMENT_ALLOWS_LINE_WRAP)
907  set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
908  if (NOT C_WCOMMENT_ALLOWS_LINE_WRAP)
909    append("-Wno-comment" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
910  endif()
911
912  # Enable -Wstring-conversion to catch misuse of string literals.
913  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
914    append("-Wstring-conversion" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
915  endif()
916
917  if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
918    # Disable the misleading indentation warning with GCC; GCC can
919    # produce noisy notes about this getting disabled in large files.
920    # See e.g. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89549
921    append("-Wno-misleading-indentation" CMAKE_CXX_FLAGS)
922  else()
923    # Prevent bugs that can happen with llvm's brace style.
924    add_flag_if_supported("-Wmisleading-indentation" MISLEADING_INDENTATION_FLAG)
925  endif()
926
927  # Enable -Wctad-maybe-unsupported to catch unintended use of CTAD.
928  add_flag_if_supported("-Wctad-maybe-unsupported" CTAD_MAYBE_UNSPPORTED_FLAG)
929endif (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
930
931if (LLVM_COMPILER_IS_GCC_COMPATIBLE AND NOT LLVM_ENABLE_WARNINGS)
932  append("-w" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
933endif()
934
935macro(append_common_sanitizer_flags)
936  if (NOT MSVC OR CLANG_CL)
937    # Append -fno-omit-frame-pointer and turn on debug info to get better
938    # stack traces.
939    append("-fno-omit-frame-pointer" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
940    if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND
941        NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO" AND
942        CMAKE_CXX_COMPILER_ID MATCHES "Clang")
943      append("-gline-tables-only" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
944    endif()
945    # Use -O1 even in debug mode, otherwise sanitizers slowdown is too large.
946    if (uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" AND LLVM_OPTIMIZE_SANITIZED_BUILDS)
947      append("-O1" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
948    endif()
949  else()
950    # Always ask the linker to produce symbols with asan.
951    append("/Z7" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
952    append("/debug" CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
953    # Not compatible with /INCREMENTAL link.
954    foreach (flags_opt_to_scrub
955        CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
956      string (REGEX REPLACE "(^| )/INCREMENTAL($| )" " /INCREMENTAL:NO "
957        "${flags_opt_to_scrub}" "${${flags_opt_to_scrub}}")
958    endforeach()
959    if (LLVM_HOST_TRIPLE MATCHES "i[2-6]86-.*")
960      # Keep frame pointers around.
961      append("/Oy-" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
962    endif()
963  endif()
964endmacro()
965
966# Turn on sanitizers if necessary.
967if(LLVM_USE_SANITIZER)
968  if (LLVM_ON_UNIX)
969    if (LLVM_USE_SANITIZER STREQUAL "Address")
970      append_common_sanitizer_flags()
971      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
972    elseif (LLVM_USE_SANITIZER STREQUAL "HWAddress")
973      append_common_sanitizer_flags()
974      append("-fsanitize=hwaddress" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
975    elseif (LLVM_USE_SANITIZER MATCHES "Memory(WithOrigins)?")
976      append_common_sanitizer_flags()
977      append("-fsanitize=memory" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
978      if(LLVM_USE_SANITIZER STREQUAL "MemoryWithOrigins")
979        append("-fsanitize-memory-track-origins" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
980      endif()
981    elseif (LLVM_USE_SANITIZER STREQUAL "Undefined")
982      append_common_sanitizer_flags()
983      append("${LLVM_UBSAN_FLAGS}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
984    elseif (LLVM_USE_SANITIZER STREQUAL "Thread")
985      append_common_sanitizer_flags()
986      append("-fsanitize=thread" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
987    elseif (LLVM_USE_SANITIZER STREQUAL "DataFlow")
988      append("-fsanitize=dataflow" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
989    elseif (LLVM_USE_SANITIZER STREQUAL "Address;Undefined" OR
990            LLVM_USE_SANITIZER STREQUAL "Undefined;Address")
991      append_common_sanitizer_flags()
992      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
993      append("${LLVM_UBSAN_FLAGS}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
994    elseif (LLVM_USE_SANITIZER STREQUAL "Leaks")
995      append_common_sanitizer_flags()
996      append("-fsanitize=leak" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
997    else()
998      message(FATAL_ERROR "Unsupported value of LLVM_USE_SANITIZER: ${LLVM_USE_SANITIZER}")
999    endif()
1000  elseif(MINGW)
1001    if (LLVM_USE_SANITIZER STREQUAL "Address")
1002      append_common_sanitizer_flags()
1003      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1004    elseif (LLVM_USE_SANITIZER STREQUAL "Undefined")
1005      append_common_sanitizer_flags()
1006      append("${LLVM_UBSAN_FLAGS}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1007    elseif (LLVM_USE_SANITIZER STREQUAL "Address;Undefined" OR
1008            LLVM_USE_SANITIZER STREQUAL "Undefined;Address")
1009      append_common_sanitizer_flags()
1010      append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1011      append("${LLVM_UBSAN_FLAGS}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1012    else()
1013      message(FATAL_ERROR "This sanitizer not yet supported in a MinGW environment: ${LLVM_USE_SANITIZER}")
1014    endif()
1015  elseif(MSVC)
1016    if (NOT LLVM_USE_SANITIZER MATCHES "^(Address|Undefined|Address;Undefined|Undefined;Address)$")
1017      message(FATAL_ERROR "This sanitizer not yet supported in the MSVC environment: ${LLVM_USE_SANITIZER}")
1018    endif()
1019    append_common_sanitizer_flags()
1020    if (LINKER_IS_LLD_LINK)
1021      if (LLVM_HOST_TRIPLE MATCHES "i[2-6]86-.*")
1022        set(arch "i386")
1023      else()
1024        set(arch "x86_64")
1025      endif()
1026      # Prepare ASAN runtime if needed
1027      if (LLVM_USE_SANITIZER MATCHES ".*Address.*")
1028        # lld string tail merging interacts badly with ASAN on Windows, turn it off here
1029        # See https://github.com/llvm/llvm-project/issues/62078
1030        append("/opt:nolldtailmerge" CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1031        if (${CMAKE_MSVC_RUNTIME_LIBRARY} MATCHES "^(MultiThreaded|MultiThreadedDebug)$")
1032          append("/wholearchive:clang_rt.asan-${arch}.lib /wholearchive:clang_rt.asan_cxx-${arch}.lib"
1033            CMAKE_EXE_LINKER_FLAGS)
1034          append("/wholearchive:clang_rt.asan_dll_thunk-${arch}.lib"
1035            CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1036        else()
1037          append("clang_rt.asan_dynamic-${arch}.lib /wholearchive:clang_rt.asan_dynamic_runtime_thunk-${arch}.lib"
1038            CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1039        endif()
1040      endif()
1041    endif()
1042    if (LLVM_USE_SANITIZER MATCHES ".*Address.*")
1043      if (NOT CLANG_CL)
1044        append("/fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1045        # Not compatible with /RTC flags.
1046        foreach (flags_opt_to_scrub
1047            CMAKE_CXX_FLAGS_${uppercase_CMAKE_BUILD_TYPE} CMAKE_C_FLAGS_${uppercase_CMAKE_BUILD_TYPE})
1048          string (REGEX REPLACE "(^| )/RTC[1csu]*($| )" " "
1049            "${flags_opt_to_scrub}" "${${flags_opt_to_scrub}}")
1050        endforeach()
1051      else()
1052        append("-fsanitize=address" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1053      endif()
1054    endif()
1055    if (LLVM_USE_SANITIZER MATCHES ".*Undefined.*")
1056      if (NOT CLANG_CL)
1057        message(FATAL_ERROR "This sanitizer is only supported by clang-cl: Undefined")
1058      endif()
1059      append(${LLVM_UBSAN_FLAGS} CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1060    endif()
1061  else()
1062    message(FATAL_ERROR "LLVM_USE_SANITIZER is not supported on this platform.")
1063  endif()
1064  if (LLVM_USE_SANITIZE_COVERAGE)
1065    append("-fsanitize=fuzzer-no-link" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1066  endif()
1067  if (LLVM_USE_SANITIZER MATCHES ".*Undefined.*")
1068    set(IGNORELIST_FILE "${PROJECT_SOURCE_DIR}/utils/sanitizers/ubsan_ignorelist.txt")
1069    if (EXISTS "${IGNORELIST_FILE}")
1070      # Use this option name version since -fsanitize-ignorelist is only
1071      # accepted with clang 13.0 or newer.
1072      append("-fsanitize-blacklist=${IGNORELIST_FILE}"
1073             CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1074    endif()
1075  endif()
1076endif()
1077
1078# Turn on -gsplit-dwarf if requested in debug builds.
1079if (LLVM_USE_SPLIT_DWARF AND
1080    ((uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG") OR
1081     (uppercase_CMAKE_BUILD_TYPE STREQUAL "RELWITHDEBINFO")))
1082  # Limit to clang and gcc so far. Add compilers supporting this option.
1083  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR
1084      CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
1085    add_compile_options($<$<COMPILE_LANGUAGE:C,CXX>:-gsplit-dwarf>)
1086    include(CheckLinkerFlag)
1087    check_linker_flag(CXX "-Wl,--gdb-index" LINKER_SUPPORTS_GDB_INDEX)
1088    append_if(LINKER_SUPPORTS_GDB_INDEX "-Wl,--gdb-index"
1089      CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1090  endif()
1091endif()
1092
1093add_compile_definitions(__STDC_CONSTANT_MACROS)
1094add_compile_definitions(__STDC_FORMAT_MACROS)
1095add_compile_definitions(__STDC_LIMIT_MACROS)
1096
1097# clang and gcc don't default-print colored diagnostics when invoked from Ninja.
1098if (UNIX AND
1099    CMAKE_GENERATOR MATCHES "Ninja" AND
1100    (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR
1101     (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
1102      NOT (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9))))
1103  append("-fdiagnostics-color" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1104endif()
1105
1106# lld doesn't print colored diagnostics when invoked from Ninja
1107if (UNIX AND CMAKE_GENERATOR MATCHES "Ninja")
1108  include(CheckLinkerFlag)
1109  check_linker_flag(CXX "-Wl,--color-diagnostics" LINKER_SUPPORTS_COLOR_DIAGNOSTICS)
1110  append_if(LINKER_SUPPORTS_COLOR_DIAGNOSTICS "-Wl,--color-diagnostics"
1111    CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1112endif()
1113
1114# Add flags for add_dead_strip().
1115# FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF?
1116# But MinSizeRel seems to add that automatically, so maybe disable these
1117# flags instead if LLVM_NO_DEAD_STRIP is set.
1118if(NOT CYGWIN AND NOT MSVC)
1119  if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin" AND
1120     NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
1121    if (CMAKE_CXX_COMPILER_ID MATCHES "XL")
1122      append("-qfuncsect" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1123    else()
1124      append("-ffunction-sections" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1125    endif()
1126    append("-fdata-sections" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1127  endif()
1128elseif(MSVC)
1129  if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" )
1130    append("/Gw" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1131  endif()
1132endif()
1133
1134if(MSVC)
1135  # Remove flags here, for exceptions and RTTI.
1136  # Each target property or source property should be responsible to control
1137  # them.
1138  # CL.EXE complains to override flags like "/GR /GR-".
1139  string(REGEX REPLACE "(^| ) */EH[-cs]+ *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
1140  string(REGEX REPLACE "(^| ) */GR-? *( |$)" "\\1 \\2" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
1141endif()
1142
1143# Provide public options to globally control RTTI and EH
1144option(LLVM_ENABLE_EH "Enable Exception handling" OFF)
1145option(LLVM_ENABLE_RTTI "Enable run time type information" OFF)
1146if(LLVM_ENABLE_EH AND NOT LLVM_ENABLE_RTTI)
1147  message(FATAL_ERROR "Exception handling requires RTTI. You must set LLVM_ENABLE_RTTI to ON")
1148endif()
1149
1150option(LLVM_ENABLE_IR_PGO "Build LLVM and tools with IR PGO instrumentation (deprecated)" Off)
1151mark_as_advanced(LLVM_ENABLE_IR_PGO)
1152
1153set(LLVM_BUILD_INSTRUMENTED OFF CACHE STRING "Build LLVM and tools with PGO instrumentation. May be specified as IR or Frontend")
1154set(LLVM_VP_COUNTERS_PER_SITE "1.5" CACHE STRING "Value profile counters to use per site for IR PGO with Clang")
1155mark_as_advanced(LLVM_BUILD_INSTRUMENTED LLVM_VP_COUNTERS_PER_SITE)
1156string(TOUPPER "${LLVM_BUILD_INSTRUMENTED}" uppercase_LLVM_BUILD_INSTRUMENTED)
1157
1158if (LLVM_BUILD_INSTRUMENTED)
1159  if (LLVM_ENABLE_IR_PGO OR uppercase_LLVM_BUILD_INSTRUMENTED STREQUAL "IR")
1160    append("-fprofile-generate=\"${LLVM_PROFILE_DATA_DIR}\""
1161      CMAKE_CXX_FLAGS
1162      CMAKE_C_FLAGS)
1163    if(NOT LINKER_IS_LLD_LINK)
1164      append("-fprofile-generate=\"${LLVM_PROFILE_DATA_DIR}\""
1165        CMAKE_EXE_LINKER_FLAGS
1166        CMAKE_SHARED_LINKER_FLAGS)
1167    endif()
1168    # Set this to avoid running out of the value profile node section
1169    # under clang in dynamic linking mode.
1170    if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND
1171        CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 11 AND
1172        LLVM_LINK_LLVM_DYLIB)
1173      append("-Xclang -mllvm -Xclang -vp-counters-per-site=${LLVM_VP_COUNTERS_PER_SITE}"
1174        CMAKE_CXX_FLAGS
1175        CMAKE_C_FLAGS)
1176    endif()
1177  elseif(uppercase_LLVM_BUILD_INSTRUMENTED STREQUAL "CSIR")
1178    append("-fcs-profile-generate=\"${LLVM_CSPROFILE_DATA_DIR}\""
1179      CMAKE_CXX_FLAGS
1180      CMAKE_C_FLAGS)
1181    if(NOT LINKER_IS_LLD_LINK)
1182      append("-fcs-profile-generate=\"${LLVM_CSPROFILE_DATA_DIR}\""
1183        CMAKE_EXE_LINKER_FLAGS
1184        CMAKE_SHARED_LINKER_FLAGS)
1185    endif()
1186  else()
1187    append("-fprofile-instr-generate=\"${LLVM_PROFILE_FILE_PATTERN}\""
1188      CMAKE_CXX_FLAGS
1189      CMAKE_C_FLAGS)
1190    if(NOT LINKER_IS_LLD_LINK)
1191      append("-fprofile-instr-generate=\"${LLVM_PROFILE_FILE_PATTERN}\""
1192        CMAKE_EXE_LINKER_FLAGS
1193        CMAKE_SHARED_LINKER_FLAGS)
1194    endif()
1195  endif()
1196endif()
1197
1198# When using clang-cl with an instrumentation-based tool, add clang's library
1199# resource directory to the library search path. Because cmake invokes the
1200# linker directly, it isn't sufficient to pass -fsanitize=* to the linker.
1201if (CLANG_CL AND (LLVM_BUILD_INSTRUMENTED OR LLVM_USE_SANITIZER))
1202  execute_process(
1203    COMMAND ${CMAKE_CXX_COMPILER} /clang:-print-libgcc-file-name /clang:--rtlib=compiler-rt
1204    OUTPUT_VARIABLE clang_compiler_rt_file
1205    ERROR_VARIABLE clang_cl_stderr
1206    OUTPUT_STRIP_TRAILING_WHITESPACE
1207    ERROR_STRIP_TRAILING_WHITESPACE
1208    RESULT_VARIABLE clang_cl_exit_code)
1209  if (NOT "${clang_cl_exit_code}" STREQUAL "0")
1210    message(FATAL_ERROR
1211      "Unable to invoke clang-cl to find resource dir: ${clang_cl_stderr}")
1212  endif()
1213  file(TO_CMAKE_PATH "${clang_compiler_rt_file}" clang_compiler_rt_file)
1214  get_filename_component(clang_runtime_dir "${clang_compiler_rt_file}" DIRECTORY)
1215  prepend("${CMAKE_CXX_LINKER_WRAPPER_FLAG}/libpath:\"${clang_runtime_dir}\""
1216    CMAKE_EXE_LINKER_FLAGS
1217    CMAKE_MODULE_LINKER_FLAGS
1218    CMAKE_SHARED_LINKER_FLAGS)
1219endif()
1220
1221if(LLVM_PROFDATA_FILE AND EXISTS ${LLVM_PROFDATA_FILE})
1222  if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" )
1223    append("-fprofile-instr-use=\"${LLVM_PROFDATA_FILE}\""
1224      CMAKE_CXX_FLAGS
1225      CMAKE_C_FLAGS)
1226    if(NOT LINKER_IS_LLD_LINK)
1227      append("-fprofile-instr-use=\"${LLVM_PROFDATA_FILE}\""
1228        CMAKE_EXE_LINKER_FLAGS
1229        CMAKE_SHARED_LINKER_FLAGS)
1230    endif()
1231  else()
1232    message(FATAL_ERROR "LLVM_PROFDATA_FILE can only be specified when compiling with clang")
1233  endif()
1234endif()
1235
1236option(LLVM_BUILD_INSTRUMENTED_COVERAGE "Build LLVM and tools with Code Coverage instrumentation" Off)
1237option(LLVM_INDIVIDUAL_TEST_COVERAGE "Emit individual coverage file for each test case." OFF)
1238mark_as_advanced(LLVM_BUILD_INSTRUMENTED_COVERAGE)
1239append_if(LLVM_BUILD_INSTRUMENTED_COVERAGE "-fprofile-instr-generate=\"${LLVM_PROFILE_FILE_PATTERN}\" -fcoverage-mapping"
1240  CMAKE_CXX_FLAGS
1241  CMAKE_C_FLAGS
1242  CMAKE_EXE_LINKER_FLAGS
1243  CMAKE_SHARED_LINKER_FLAGS)
1244
1245if (LLVM_BUILD_INSTRUMENTED AND LLVM_BUILD_INSTRUMENTED_COVERAGE)
1246  message(FATAL_ERROR "LLVM_BUILD_INSTRUMENTED and LLVM_BUILD_INSTRUMENTED_COVERAGE cannot both be specified")
1247endif()
1248
1249set(LLVM_THINLTO_CACHE_PATH "${PROJECT_BINARY_DIR}/lto.cache" CACHE STRING "Set ThinLTO cache path. This can be used when building LLVM from several different directiories.")
1250
1251if(LLVM_ENABLE_LTO AND LLVM_ON_WIN32 AND NOT LINKER_IS_LLD_LINK AND NOT MINGW)
1252  message(FATAL_ERROR "When compiling for Windows, LLVM_ENABLE_LTO requires using lld as the linker (point CMAKE_LINKER at lld-link.exe)")
1253endif()
1254if(uppercase_LLVM_ENABLE_LTO STREQUAL "THIN")
1255  append("-flto=thin" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
1256  if(NOT LINKER_IS_LLD_LINK)
1257    append("-flto=thin" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1258  endif()
1259  # If the linker supports it, enable the lto cache. This improves initial build
1260  # time a little since we re-link a lot of the same objects, and significantly
1261  # improves incremental build time.
1262  # FIXME: We should move all this logic into the clang driver.
1263  if(APPLE)
1264    append("-Wl,-cache_path_lto,${LLVM_THINLTO_CACHE_PATH}"
1265           CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1266  elseif((UNIX OR MINGW) AND LLVM_USE_LINKER STREQUAL "lld")
1267    append("-Wl,--thinlto-cache-dir=${LLVM_THINLTO_CACHE_PATH}"
1268           CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1269  elseif(LLVM_USE_LINKER STREQUAL "gold")
1270    append("-Wl,--plugin-opt,cache-dir=${LLVM_THINLTO_CACHE_PATH}"
1271           CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1272  elseif(LINKER_IS_LLD_LINK)
1273    append("/lldltocache:${LLVM_THINLTO_CACHE_PATH}"
1274           CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1275  endif()
1276elseif(uppercase_LLVM_ENABLE_LTO STREQUAL "FULL")
1277  append("-flto=full" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
1278  if(NOT LINKER_IS_LLD_LINK)
1279    append("-flto=full" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1280  endif()
1281elseif(LLVM_ENABLE_LTO)
1282  append("-flto" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
1283  if(NOT LINKER_IS_LLD_LINK)
1284    append("-flto" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
1285  endif()
1286endif()
1287
1288if(LLVM_ENABLE_FATLTO AND ((UNIX AND NOT APPLE) OR FUCHSIA))
1289  append("-ffat-lto-objects" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1290  if(NOT LINKER_IS_LLD_LINK)
1291    append("-ffat-lto-objects" CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS)
1292  endif()
1293endif()
1294
1295# Set an AIX default for LLVM_EXPORT_SYMBOLS_FOR_PLUGINS based on whether we are
1296# doing dynamic linking (see below).
1297set(LLVM_EXPORT_SYMBOLS_FOR_PLUGINS_AIX_default OFF)
1298if (NOT (BUILD_SHARED_LIBS OR LLVM_LINK_LLVM_DYLIB))
1299  set(LLVM_EXPORT_SYMBOLS_FOR_PLUGINS_AIX_default ON)
1300endif()
1301
1302# This option makes utils/extract_symbols.py be used to determine the list of
1303# symbols to export from LLVM tools. This is necessary when on AIX or when using
1304# MSVC if you want to allow plugins. On AIX we don't show this option, and we
1305# enable it by default except when the LLVM libraries are set up for dynamic
1306# linking (due to incompatibility). With MSVC, note that the plugin has to
1307# explicitly link against (exactly one) tool so we can't unilaterally turn on
1308# LLVM_ENABLE_PLUGINS when it's enabled.
1309CMAKE_DEPENDENT_OPTION(LLVM_EXPORT_SYMBOLS_FOR_PLUGINS
1310       "Export symbols from LLVM tools so that plugins can import them" OFF
1311       "NOT ${CMAKE_SYSTEM_NAME} MATCHES AIX" ${LLVM_EXPORT_SYMBOLS_FOR_PLUGINS_AIX_default})
1312if(BUILD_SHARED_LIBS AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
1313  message(FATAL_ERROR "BUILD_SHARED_LIBS not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS")
1314endif()
1315if(LLVM_LINK_LLVM_DYLIB AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
1316  message(FATAL_ERROR "LLVM_LINK_LLVM_DYLIB not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS")
1317endif()
1318
1319# By default we should enable LLVM_ENABLE_IDE only for multi-configuration
1320# generators. This option disables optional build system features that make IDEs
1321# less usable.
1322set(LLVM_ENABLE_IDE_default OFF)
1323if (CMAKE_CONFIGURATION_TYPES)
1324  set(LLVM_ENABLE_IDE_default ON)
1325endif()
1326option(LLVM_ENABLE_IDE
1327       "Disable optional build system features that cause problems for IDE generators"
1328       ${LLVM_ENABLE_IDE_default})
1329if (CMAKE_CONFIGURATION_TYPES AND NOT LLVM_ENABLE_IDE)
1330  message(WARNING "Disabling LLVM_ENABLE_IDE on multi-configuration generators is not recommended.")
1331endif()
1332
1333function(get_compile_definitions)
1334  get_directory_property(top_dir_definitions DIRECTORY ${CMAKE_SOURCE_DIR} COMPILE_DEFINITIONS)
1335  foreach(definition ${top_dir_definitions})
1336    if(DEFINED result)
1337      string(APPEND result " -D${definition}")
1338    else()
1339      set(result "-D${definition}")
1340    endif()
1341  endforeach()
1342  set(LLVM_DEFINITIONS "${result}" PARENT_SCOPE)
1343endfunction()
1344get_compile_definitions()
1345
1346option(LLVM_FORCE_ENABLE_STATS "Enable statistics collection for builds that wouldn't normally enable it" OFF)
1347
1348check_symbol_exists(os_signpost_interval_begin "os/signpost.h" macos_signposts_available)
1349if(macos_signposts_available)
1350  check_cxx_source_compiles(
1351    "#include <os/signpost.h>
1352    int main() { os_signpost_interval_begin(nullptr, 0, \"\", \"\"); return 0; }"
1353    macos_signposts_usable)
1354  if(macos_signposts_usable)
1355    set(LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS "WITH_ASSERTS" CACHE STRING
1356        "Enable support for Xcode signposts. Can be WITH_ASSERTS, FORCE_ON, FORCE_OFF")
1357    string(TOUPPER "${LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS}"
1358                   uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS)
1359    if( uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS STREQUAL "WITH_ASSERTS" )
1360      if( LLVM_ENABLE_ASSERTIONS )
1361        set( LLVM_SUPPORT_XCODE_SIGNPOSTS 1 )
1362      endif()
1363    elseif( uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS STREQUAL "FORCE_ON" )
1364      set( LLVM_SUPPORT_XCODE_SIGNPOSTS 1 )
1365    elseif( uppercase_LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS STREQUAL "FORCE_OFF" )
1366      # We don't need to do anything special to turn off signposts.
1367    elseif( NOT DEFINED LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS )
1368      # Treat LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS like "FORCE_OFF" when it has not been
1369      # defined.
1370    else()
1371      message(FATAL_ERROR "Unknown value for LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS:"
1372                          " \"${LLVM_ENABLE_SUPPORT_XCODE_SIGNPOSTS}\"!")
1373    endif()
1374  endif()
1375endif()
1376
1377set(LLVM_SOURCE_PREFIX "" CACHE STRING "Use prefix for sources")
1378
1379option(LLVM_USE_RELATIVE_PATHS_IN_DEBUG_INFO "Use relative paths in debug info" OFF)
1380
1381if(LLVM_USE_RELATIVE_PATHS_IN_DEBUG_INFO)
1382  check_c_compiler_flag("-fdebug-prefix-map=foo=bar" SUPPORTS_FDEBUG_PREFIX_MAP)
1383  if(LLVM_ENABLE_PROJECTS_USED)
1384    get_filename_component(source_root "${LLVM_MAIN_SRC_DIR}/.." ABSOLUTE)
1385  else()
1386    set(source_root "${LLVM_MAIN_SRC_DIR}")
1387  endif()
1388  file(RELATIVE_PATH relative_root "${CMAKE_BINARY_DIR}" "${source_root}")
1389  append_if(SUPPORTS_FDEBUG_PREFIX_MAP "-fdebug-prefix-map=${CMAKE_BINARY_DIR}=${relative_root}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1390  append_if(SUPPORTS_FDEBUG_PREFIX_MAP "-fdebug-prefix-map=${source_root}/=${LLVM_SOURCE_PREFIX}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1391  if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
1392    append("-no-canonical-prefixes" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1393  endif()
1394endif()
1395
1396option(LLVM_USE_RELATIVE_PATHS_IN_FILES "Use relative paths in sources and debug info" OFF)
1397
1398if(LLVM_USE_RELATIVE_PATHS_IN_FILES)
1399  check_c_compiler_flag("-ffile-prefix-map=foo=bar" SUPPORTS_FFILE_PREFIX_MAP)
1400  if(LLVM_ENABLE_PROJECTS_USED)
1401    get_filename_component(source_root "${LLVM_MAIN_SRC_DIR}/.." ABSOLUTE)
1402  else()
1403    set(source_root "${LLVM_MAIN_SRC_DIR}")
1404  endif()
1405  file(RELATIVE_PATH relative_root "${CMAKE_BINARY_DIR}" "${source_root}")
1406  append_if(SUPPORTS_FFILE_PREFIX_MAP "-ffile-prefix-map=${CMAKE_BINARY_DIR}=${relative_root}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1407  append_if(SUPPORTS_FFILE_PREFIX_MAP "-ffile-prefix-map=${source_root}/=${LLVM_SOURCE_PREFIX}" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1408  if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
1409    append("-no-canonical-prefixes" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
1410  endif()
1411endif()
1412
1413set(LLVM_THIRD_PARTY_DIR  ${CMAKE_CURRENT_SOURCE_DIR}/../third-party CACHE STRING
1414    "Directory containing third party software used by LLVM (e.g. googletest)")
1415
1416set(LLVM_UNITTEST_LINK_FLAGS "" CACHE STRING
1417    "Additional linker flags for unit tests")
1418
1419if(LLVM_ENABLE_LLVM_LIBC)
1420  check_library_exists(llvmlibc printf "" HAVE_LLVM_LIBC)
1421  if(NOT HAVE_LLVM_LIBC)
1422    message(WARNING "Unable to link against LLVM libc. LLVM will be built without linking against the LLVM libc overlay.")
1423  endif()
1424endif()
1425