[cmake][wip] Add support for setting crash report directory

[paulkirth]

Summary

Crash reports and reproducers can be saved to a directory through
-fcrash-diagnostics-dir. This patch adds a CMAKE variable and plumbs
it through to the runtimes build targets in addition to Clang/LLVM

[paulkirth]

Actually passthrough/update the variable in the runtimes build.
Remove debugging code.

[paulkirth]

Is there a way to write a test for CMAKE?

[Mordante]

This seems to solve the same issue as D133082, have you seen that patch?

[paulkirth]

@Mordante I had not seen that, so thanks for pointing this out.

[paulkirth]

D133082 has landed, making this change redundant

llvm/CMakeLists.txt

 
 set(LLVM_ENABLE_NEW_PASS_MANAGER TRUE CACHE BOOL
   "Enable the new pass manager by default.")
 if(NOT LLVM_ENABLE_NEW_PASS_MANAGER)
   message(FATAL_ERROR "Enabling the legacy pass manager on the cmake level is"
                       " no longer supported.")
 endif()
 
+set(LLVM_CRASH_REPORT_DIR "" CACHE STRING "Define directory name for crash reports" )
+
 include(HandleLLVMOptions)
 
 ######
 
 # Configure all of the various header file fragments LLVM uses which depend on
 # configuration variables.
 set(LLVM_ENUM_TARGETS "")
 set(LLVM_ENUM_ASM_PRINTERS "")

llvm/cmake/modules/HandleLLVMOptions.cmake

if (MSVC)
           CMAKE_C_FLAGS_MINSIZEREL)
         string (REGEX REPLACE "(^| )[/-]D *NDEBUG($| )" " "
           "${flags_var_to_scrub}" "${${flags_var_to_scrub}}")
       endforeach()
      endif()
   endif()
 endif()
 
+if(DEFINED LLVM_CRASH_REPORT_DIR AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  append("-fcrash-diagnostics-dir=${LLVM_CRASH_REPORT_DIR}" CMAKE_CXX_FLAGS CMAKE_C_FLAGS)
+endif()
+
 if(LLVM_ENABLE_EXPENSIVE_CHECKS)
   add_definitions(-DEXPENSIVE_CHECKS)
 
   # In some libstdc++ versions, std::min_element is not constexpr when
   # _GLIBCXX_DEBUG is enabled.
   CHECK_CXX_SOURCE_COMPILES("
     #define _GLIBCXX_DEBUG
     #include <algorithm>

llvm/runtimes/CMakeLists.txt

llvm_ExternalProject_Add(builtins
                                       -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=${LLVM_ENABLE_PER_TARGET_RUNTIME_DIR_default}
                                       -DCMAKE_C_COMPILER_WORKS=ON
                                       -DCMAKE_ASM_COMPILER_WORKS=ON
                                       ${COMMON_CMAKE_ARGS}
                                       ${BUILTINS_CMAKE_ARGS}
                            PASSTHROUGH_PREFIXES COMPILER_RT
                                                 DARWIN
                                                 SANITIZER
+                                                LLVM_CRASH_REPORT_DIR
                            USE_TOOLCHAIN
                            TARGET_TRIPLE ${LLVM_TARGET_TRIPLE}
                            ${EXTRA_ARGS})
 endfunction()
 
 function(builtin_register_target compiler_rt_path target)
   cmake_parse_arguments(ARG "" "" "DEPENDS" ${ARGN})
 
llvm_ExternalProject_Add(runtimes
                                       -DLLVM_BUILD_TOOLS=${LLVM_BUILD_TOOLS}
                                       -DCMAKE_C_COMPILER_WORKS=ON
                                       -DCMAKE_CXX_COMPILER_WORKS=ON
                                       -DCMAKE_ASM_COMPILER_WORKS=ON
                                       ${COMMON_CMAKE_ARGS}
                                       ${RUNTIMES_CMAKE_ARGS}
                            PASSTHROUGH_PREFIXES LLVM_ENABLE_RUNTIMES
                                                 LLVM_USE_LINKER
+                                                LLVM_CRASH_REPORT_DIR
                                                 ${ARG_PREFIXES}
                            EXTRA_TARGETS ${extra_targets}
                                          ${test_targets}
                                          ${SUB_COMPONENTS}
                                          ${SUB_CHECK_TARGETS}
                                          ${SUB_INSTALL_TARGETS}
                            USE_TOOLCHAIN
                            TARGET_TRIPLE ${LLVM_TARGET_TRIPLE}
if(NOT RUNTIMES_${name}_LLVM_ENABLE_RUNTIMES AND NOT RUNTIMES_${target}_LLVM_ENABLE_RUNTIMES)
     string(REPLACE ";" "|" LLVM_ENABLE_RUNTIMES_PASSTHROUGH "${LLVM_ENABLE_RUNTIMES}")
     list(APPEND ${name}_extra_args -DLLVM_ENABLE_RUNTIMES=${LLVM_ENABLE_RUNTIMES_PASSTHROUGH})
   endif()
 
   if(NOT RUNTIMES_${name}_LLVM_USE_LINKER AND NOT RUNTIMES_${target}_LLVM_USE_LINKER)
     list(APPEND ${name}_extra_args -DLLVM_USE_LINKER=${LLVM_USE_LINKER})
   endif()
 
+  if(NOT RUNTIMES_${name}_LLVM_CRASH_REPORT_DIR AND NOT RUNTIMES_${target}_LLVM_CRASH_REPORT_DIR)
+    list(APPEND ${name}_extra_args -DLLVM_CRASH_REPORT_DIR=${LLVM_CRASH_REPORT_DIR})
+  endif()
+
   llvm_ExternalProject_Add(runtimes-${name}
                            ${CMAKE_CURRENT_SOURCE_DIR}/../../runtimes
                            DEPENDS ${${name}_deps}
                            # Builtins were built separately above
                            CMAKE_ARGS -DCOMPILER_RT_BUILD_BUILTINS=Off
                                       -DLLVM_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
                                       -DLLVM_DEFAULT_TARGET_TRIPLE=${target}
                                       -DLLVM_ENABLE_PROJECTS_USED=${LLVM_ENABLE_PROJECTS_USED}