[CMake] Add PARENT_TARGET option to add_sanitizer_rt_symbols.

[beanz]

Summary

This is another step in a multi-step refactoring to move add_sanitizer_rt_symbols in the direction of other add_* functions in compiler-rt.

[filcab]

LGTM

compiler-rt/trunk/cmake/Modules/SanitizerUtils.cmake

 set(SANITIZER_GEN_DYNAMIC_LIST
   ${COMPILER_RT_SOURCE_DIR}/lib/sanitizer_common/scripts/gen_dynamic_list.py)
 
 set(SANITIZER_LINT_SCRIPT
   ${COMPILER_RT_SOURCE_DIR}/lib/sanitizer_common/scripts/check_lint.sh)
 
 # Create a target "<name>-symbols" that would generate the list of symbols
 # that need to be exported from sanitizer runtime "<name>". Function
 # interceptors are exported automatically, user can also provide files with
 # symbol names that should be exported as well.
 #   add_sanitizer_rt_symbols(<name>
+#                            PARENT_TARGET <convenience parent target>
 #                            EXTRA <files with extra symbols to export>)
 macro(add_sanitizer_rt_symbols name)
   cmake_parse_arguments(ARG
     ""
-    ""
+    "PARENT_TARGET"
     "EXTRA"
     ${ARGN})
   set(stamp ${CMAKE_CURRENT_BINARY_DIR}/${name}.syms-stamp)
   set(extra_args)
   foreach(arg ${ARG_EXTRA})
     list(APPEND extra_args "--extra" ${arg})
   endforeach()
   add_custom_command(OUTPUT ${stamp}
if(CMAKE_CONFIGURATION_TYPES)
         install(FILES ${libfile}.syms CONFIGURATIONS ${c}
           DESTINATION ${COMPILER_RT_LIBRARY_INSTALL_DIR})
       endforeach()
     else()
       get_target_property(libfile ${name} LOCATION_${CMAKE_BUILD_TYPE})
       install(FILES ${libfile}.syms DESTINATION ${COMPILER_RT_LIBRARY_INSTALL_DIR})
     endif()
   endif()
+  if(ARG_PARENT_TARGET)
+    add_dependencies(${ARG_PARENT_TARGET} ${name}-symbols)
+  endif()
 endmacro()
 
 macro(add_sanitizer_rt_version_list name)
   set(vers ${CMAKE_CURRENT_BINARY_DIR}/${name}.vers)
   cmake_parse_arguments(ARG "" "" "LIBS;EXTRA" ${ARGN})
   set(args)
   foreach(arg ${ARG_EXTRA})
     list(APPEND args "--extra" ${arg})

compiler-rt/trunk/lib/ubsan/CMakeLists.txt

add_compiler_rt_runtime(clang_rt.ubsan_standalone_cxx
       ARCHS ${UBSAN_SUPPORTED_ARCH}
       OBJECT_LIBS RTUbsan_cxx
       CFLAGS ${UBSAN_CXXFLAGS}
       PARENT_TARGET ubsan)
 
     foreach(arch ${UBSAN_SUPPORTED_ARCH})
       if (UNIX AND NOT ${arch} MATCHES "i386|i686")
         add_sanitizer_rt_symbols(clang_rt.ubsan_standalone-${arch}
+          PARENT_TARGET ubsan
           EXTRA ubsan.syms.extra)
         add_sanitizer_rt_symbols(clang_rt.ubsan_standalone_cxx-${arch}
+          PARENT_TARGET ubsan
           EXTRA ubsan.syms.extra)
-        add_dependencies(ubsan
-          clang_rt.ubsan_standalone-${arch}-symbols
-          clang_rt.ubsan_standalone_cxx-${arch}-symbols)
       endif()
     endforeach()
   endif()
 endif()
 
 add_dependencies(compiler-rt ubsan)