1set(OBJECT_LIBRARY_TARGET_TYPE "OBJECT_LIBRARY") 2 3# Rule which is essentially a wrapper over add_library to compile a set of 4# sources to object files. 5# Usage: 6# add_object_library( 7# <target_name> 8# HDRS <list of header files> 9# SRCS <list of source files> 10# DEPENDS <list of dependencies> 11# COMPILE_OPTIONS <optional list of special compile options for this target> 12function(add_object_library target_name) 13 cmake_parse_arguments( 14 "ADD_OBJECT" 15 "" # No option arguments 16 "" # Single value arguments 17 "SRCS;HDRS;COMPILE_OPTIONS;DEPENDS" # Multivalue arguments 18 ${ARGN} 19 ) 20 21 if(NOT ADD_OBJECT_SRCS) 22 message(FATAL_ERROR "'add_object_library' rule requires SRCS to be specified.") 23 endif() 24 25 get_fq_target_name(${target_name} fq_target_name) 26 add_library( 27 ${fq_target_name} 28 EXCLUDE_FROM_ALL 29 OBJECT 30 ${ADD_OBJECT_SRCS} 31 ${ADD_OBJECT_HDRS} 32 ) 33 target_include_directories( 34 ${fq_target_name} 35 PRIVATE 36 ${LIBC_BUILD_DIR}/include 37 ${LIBC_SOURCE_DIR} 38 ${LIBC_BUILD_DIR} 39 ) 40 if(ADD_OBJECT_COMPILE_OPTIONS) 41 target_compile_options( 42 ${fq_target_name} 43 PRIVATE ${ADD_OBJECT_COMPILE_OPTIONS} 44 ) 45 endif() 46 47 get_fq_deps_list(fq_deps_list ${ADD_OBJECT_DEPENDS}) 48 if(fq_deps_list) 49 add_dependencies(${fq_target_name} ${fq_deps_list}) 50 endif() 51 52 set_target_properties( 53 ${fq_target_name} 54 PROPERTIES 55 "TARGET_TYPE" ${OBJECT_LIBRARY_TARGET_TYPE} 56 "OBJECT_FILES" "$<TARGET_OBJECTS:${fq_target_name}>" 57 "DEPS" "${fq_deps_list}" 58 ) 59endfunction(add_object_library) 60 61set(ENTRYPOINT_OBJ_TARGET_TYPE "ENTRYPOINT_OBJ") 62 63# A rule for entrypoint object targets. 64# Usage: 65# add_entrypoint_object( 66# <target_name> 67# [ALIAS|REDIRECTED] # Specified if the entrypoint is redirected or an alias. 68# [NAME] <the C name of the entrypoint if different from target_name> 69# SRCS <list of .cpp files> 70# HDRS <list of .h files> 71# DEPENDS <list of dependencies> 72# COMPILE_OPTIONS <optional list of special compile options for this target> 73# SPECIAL_OBJECTS <optional list of special object targets added by the rule `add_object`> 74# ) 75function(add_entrypoint_object target_name) 76 cmake_parse_arguments( 77 "ADD_ENTRYPOINT_OBJ" 78 "ALIAS;REDIRECTED" # Optional argument 79 "NAME" # Single value arguments 80 "SRCS;HDRS;DEPENDS;COMPILE_OPTIONS" # Multi value arguments 81 ${ARGN} 82 ) 83 84 get_fq_target_name(${target_name} fq_target_name) 85 set(entrypoint_name ${target_name}) 86 if(ADD_ENTRYPOINT_OBJ_NAME) 87 set(entrypoint_name ${ADD_ENTRYPOINT_OBJ_NAME}) 88 endif() 89 90 list(FIND TARGET_ENTRYPOINT_NAME_LIST ${entrypoint_name} entrypoint_name_index) 91 if(${entrypoint_name_index} EQUAL -1) 92 add_custom_target(${fq_target_name}) 93 set_target_properties( 94 ${fq_target_name} 95 PROPERTIES 96 "ENTRYPOINT_NAME" ${entrypoint_name} 97 "TARGET_TYPE" ${ENTRYPOINT_OBJ_TARGET_TYPE} 98 "OBJECT_FILE" "" 99 "OBJECT_FILE_RAW" "" 100 "DEPS" "" 101 "SKIPPED" "YES" 102 ) 103 message(STATUS "Skipping libc entrypoint ${fq_target_name}.") 104 return() 105 endif() 106 107 if(ADD_ENTRYPOINT_OBJ_ALIAS) 108 # Alias targets help one add aliases to other entrypoint object targets. 109 # One can use alias targets setup OS/machine independent entrypoint targets. 110 list(LENGTH ADD_ENTRYPOINT_OBJ_DEPENDS deps_size) 111 if(NOT (${deps_size} EQUAL "1")) 112 message(FATAL_ERROR "An entrypoint alias should have exactly one dependency.") 113 endif() 114 list(GET ADD_ENTRYPOINT_OBJ_DEPENDS 0 dep_target) 115 get_fq_dep_name(fq_dep_name ${dep_target}) 116 if(NOT TARGET ${fq_dep_name}) 117 message(WARNING "Aliasee ${fq_dep_name} for entrypoint alias ${target_name} missing; " 118 "Target ${target_name} will be ignored.") 119 return() 120 endif() 121 122 get_target_property(obj_type ${fq_dep_name} "TARGET_TYPE") 123 if((NOT obj_type) OR (NOT (${obj_type} STREQUAL ${ENTRYPOINT_OBJ_TARGET_TYPE}))) 124 message(FATAL_ERROR "The aliasee of an entrypoint alias should be an entrypoint.") 125 endif() 126 127 add_custom_target(${fq_target_name}) 128 add_dependencies(${fq_target_name} ${fq_dep_name}) 129 get_target_property(object_file ${fq_dep_name} "OBJECT_FILE") 130 get_target_property(object_file_raw ${fq_dep_name} "OBJECT_FILE_RAW") 131 set_target_properties( 132 ${fq_target_name} 133 PROPERTIES 134 "ENTRYPOINT_NAME" ${entrypoint_name} 135 "TARGET_TYPE" ${ENTRYPOINT_OBJ_TARGET_TYPE} 136 "IS_ALIAS" "YES" 137 "OBJECT_FILE" "" 138 "OBJECT_FILE_RAW" "" 139 "DEPS" "${fq_dep_name}" 140 ) 141 return() 142 endif() 143 144 if(NOT ADD_ENTRYPOINT_OBJ_SRCS) 145 message(FATAL_ERROR "`add_entrypoint_object` rule requires SRCS to be specified.") 146 endif() 147 if(NOT ADD_ENTRYPOINT_OBJ_HDRS) 148 message(FATAL_ERROR "`add_entrypoint_object` rule requires HDRS to be specified.") 149 endif() 150 151 set(common_compile_options -fpie ${LLVM_CXX_STD_default} -ffreestanding ${ADD_ENTRYPOINT_OBJ_COMPILE_OPTIONS}) 152 set(internal_target_name ${fq_target_name}.__internal__) 153 set(include_dirs ${LIBC_BUILD_DIR}/include ${LIBC_SOURCE_DIR} ${LIBC_BUILD_DIR}) 154 get_fq_deps_list(fq_deps_list ${ADD_ENTRYPOINT_OBJ_DEPENDS}) 155 set(full_deps_list ${fq_deps_list} libc.src.__support.common) 156 157 add_library( 158 ${internal_target_name} 159 # TODO: We don't need an object library for internal consumption. 160 # A future change should switch this to a normal static library. 161 EXCLUDE_FROM_ALL 162 OBJECT 163 ${ADD_ENTRYPOINT_OBJ_SRCS} 164 ${ADD_ENTRYPOINT_OBJ_HDRS} 165 ) 166 target_compile_options(${internal_target_name} BEFORE PRIVATE ${common_compile_options}) 167 target_include_directories(${internal_target_name} PRIVATE ${include_dirs}) 168 add_dependencies(${internal_target_name} ${full_deps_list}) 169 170 add_library( 171 ${fq_target_name} 172 # We want an object library as the objects will eventually get packaged into 173 # an archive (like libc.a). 174 EXCLUDE_FROM_ALL 175 OBJECT 176 ${ADD_ENTRYPOINT_OBJ_SRCS} 177 ${ADD_ENTRYPOINT_OBJ_HDRS} 178 ) 179 target_compile_options( 180 ${fq_target_name} BEFORE PRIVATE ${common_compile_options} -DLLVM_LIBC_PUBLIC_PACKAGING 181 ) 182 target_include_directories(${fq_target_name} PRIVATE ${include_dirs}) 183 add_dependencies(${fq_target_name} ${full_deps_list}) 184 185 set_target_properties( 186 ${fq_target_name} 187 PROPERTIES 188 "ENTRYPOINT_NAME" ${entrypoint_name} 189 "TARGET_TYPE" ${ENTRYPOINT_OBJ_TARGET_TYPE} 190 "OBJECT_FILE" $<TARGET_OBJECTS:${fq_target_name}> 191 # TODO: We don't need to list internal object files if the internal 192 # target is a normal static library. 193 "OBJECT_FILE_RAW" $<TARGET_OBJECTS:${internal_target_name}> 194 "DEPS" "${fq_deps_list}" 195 ) 196 197 if(LLVM_LIBC_ENABLE_LINTING) 198 199 # We only want a second invocation of clang-tidy to run 200 # restrict-system-libc-headers if the compiler-resource-dir was set in 201 # order to prevent false-positives due to a mismatch between the host 202 # compiler and the compiled clang-tidy. 203 if(COMPILER_RESOURCE_DIR) 204 # We run restrict-system-libc-headers with --system-headers to prevent 205 # transitive inclusion through compler provided headers. 206 set(restrict_system_headers_check_invocation 207 COMMAND $<TARGET_FILE:clang-tidy> --system-headers 208 --checks="-*,llvmlibc-restrict-system-libc-headers" 209 # We explicitly set the resource dir here to match the 210 # resource dir of the host compiler. 211 "--extra-arg=-resource-dir=${COMPILER_RESOURCE_DIR}" 212 --quiet 213 -p ${PROJECT_BINARY_DIR} 214 ${ADD_ENTRYPOINT_OBJ_SRCS} 215 ) 216 else() 217 set(restrict_system_headers_check_invocation 218 COMMAND ${CMAKE_COMMAND} -E echo "Header file check skipped") 219 endif() 220 221 set(lint_timestamp "${CMAKE_CURRENT_BINARY_DIR}/.${target_name}.__lint_timestamp__") 222 add_custom_command( 223 OUTPUT ${lint_timestamp} 224 # --quiet is used to surpress warning statistics from clang-tidy like: 225 # Suppressed X warnings (X in non-user code). 226 # There seems to be a bug in clang-tidy where by even with --quiet some 227 # messages from clang's own diagnostics engine leak through: 228 # X warnings generated. 229 # Until this is fixed upstream, we use -fno-caret-diagnostics to surpress 230 # these. 231 COMMAND $<TARGET_FILE:clang-tidy> 232 "--extra-arg=-fno-caret-diagnostics" --quiet 233 # Path to directory containing compile_commands.json 234 -p ${PROJECT_BINARY_DIR} 235 ${ADD_ENTRYPOINT_OBJ_SRCS} 236 # See above: this might be a second invocation of clang-tidy depending on 237 # the conditions above. 238 ${restrict_system_headers_check_invocation} 239 # We have two options for running commands, add_custom_command and 240 # add_custom_target. We don't want to run the linter unless source files 241 # have changed. add_custom_target explicitly runs everytime therefore we 242 # use add_custom_command. This function requires an output file and since 243 # linting doesn't produce a file, we create a dummy file using a 244 # crossplatform touch. 245 COMMAND "${CMAKE_COMMAND}" -E touch ${lint_timestamp} 246 COMMENT "Linting... ${target_name}" 247 DEPENDS clang-tidy ${internal_target_name} ${ADD_ENTRYPOINT_OBJ_SRCS} 248 WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} 249 ) 250 251 add_custom_target(${fq_target_name}.__lint__ 252 DEPENDS ${lint_timestamp}) 253 add_dependencies(lint-libc ${fq_target_name}.__lint__) 254 add_dependencies(${fq_target_name} ${fq_target_name}.__lint__) 255 endif() 256 257endfunction(add_entrypoint_object) 258 259# Rule build a redirector object file. 260function(add_redirector_object target_name) 261 cmake_parse_arguments( 262 "REDIRECTOR_OBJECT" 263 "" # No optional arguments 264 "SRC" # The cpp file in which the redirector is defined. 265 "" # No multivalue arguments 266 ${ARGN} 267 ) 268 if(NOT REDIRECTOR_OBJECT_SRC) 269 message(FATAL_ERROR "'add_redirector_object' rule requires SRC option listing one source file.") 270 endif() 271 272 add_library( 273 ${target_name} 274 EXCLUDE_FROM_ALL 275 OBJECT 276 ${REDIRECTOR_OBJECT_SRC} 277 ) 278 target_compile_options( 279 ${target_name} 280 BEFORE PRIVATE -fPIC 281 ) 282endfunction(add_redirector_object) 283