[CMake] Pass additional CMake flags in Fuchsia cache files

[phosek]

Summary

This allows passing additional CMake flags to builtins and runtimes
build through Fuchsia cache files.

We now also set build type and enable assertions for builtins and
runtimes build which wasn't the case before, but should've been.

[cryptoad]

clang/cmake/caches/Fuchsia-stage2.cmake

69–80

This should probably go away for now if we want to have D46079.
Then I can go through the remaining warnings if that's important to have it and fix them.

clang/cmake/caches/Fuchsia-stage2.cmake

 set(CLANG_DEFAULT_CXX_STDLIB libc++ CACHE STRING "")
 set(CLANG_DEFAULT_RTLIB compiler-rt CACHE STRING "")
 
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
 set(CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "")
 set(CMAKE_C_FLAGS_RELWITHDEBINFO "-O3 -gline-tables-only -DNDEBUG" CACHE STRING "")
 set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O3 -gline-tables-only -DNDEBUG" CACHE STRING "")
 
+set(FUCHSIA_RUNTIMES_ENABLE_ASSERTIONS ON CACHE BOOL "")
+set(FUCHSIA_RUNTIMES_BUILD_TYPE Release CACHE STRING "")
+set(FUCHSIA_BUILTINS_BUILD_TYPE Release CACHE STRING "")
+
 set(LLVM_BUILTIN_TARGETS "default;x86_64-fuchsia;aarch64-fuchsia" CACHE STRING "")
 
 # Set the per-target builtins options.
 foreach(target x86_64;aarch64)
-  set(BUILTINS_${target}-fuchsia_CMAKE_SYSROOT ${FUCHSIA_${target}_SYSROOT} CACHE PATH "")
+  set(BUILTINS_${target}-fuchsia_UNIX 1 CACHE BOOL "")
   set(BUILTINS_${target}-fuchsia_CMAKE_SYSTEM_NAME Fuchsia CACHE STRING "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_BUILD_TYPE ${FUCHSIA_BUILTINS_BUILD_TYPE} CACHE STRING "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_ASM_FLAGS ${FUCHSIA_${target}_C_FLAGS} CACHE PATH "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_C_FLAGS ${FUCHSIA_${target}_C_FLAGS} CACHE PATH "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_CXX_FLAGS ${FUCHSIA_${target}_CXX_FLAGS} CACHE PATH "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_EXE_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE PATH "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_SHARED_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE PATH "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_MODULE_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE PATH "")
+  set(BUILTINS_${target}-fuchsia_CMAKE_SYSROOT ${FUCHSIA_${target}_SYSROOT} CACHE PATH "")
 endforeach()
 
 set(LLVM_RUNTIME_TARGETS "default;x86_64-fuchsia;aarch64-fuchsia;x86_64-fuchsia-asan:x86_64-fuchsia;aarch64-fuchsia-asan:aarch64-fuchsia" CACHE STRING "")
 
 # Set the default target runtimes options.
 if(NOT APPLE)
   set(LIBUNWIND_ENABLE_SHARED OFF CACHE BOOL "")
   set(LIBUNWIND_USE_COMPILER_RT ON CACHE BOOL "")
   set(LIBUNWIND_INSTALL_LIBRARY OFF CACHE BOOL "")
   set(LIBCXXABI_USE_COMPILER_RT ON CACHE BOOL "")
   set(LIBCXXABI_ENABLE_SHARED OFF CACHE BOOL "")
   set(LIBCXXABI_USE_LLVM_UNWINDER ON CACHE BOOL "")
   set(LIBCXXABI_ENABLE_STATIC_UNWINDER ON CACHE BOOL "")
   set(LIBCXXABI_INSTALL_LIBRARY OFF CACHE BOOL "")
   set(LIBCXX_USE_COMPILER_RT ON CACHE BOOL "")
   set(LIBCXX_ENABLE_SHARED OFF CACHE BOOL "")
   set(LIBCXX_ENABLE_STATIC_ABI_LIBRARY ON CACHE BOOL "")
 endif()
 
 # Set the per-target runtimes options.
 foreach(target x86_64;aarch64)
-  set(RUNTIMES_${target}-fuchsia_CMAKE_BUILD_WITH_INSTALL_RPATH ON CACHE BOOL "")
-  set(RUNTIMES_${target}-fuchsia_CMAKE_SYSROOT ${FUCHSIA_${target}_SYSROOT} CACHE PATH "")
-  set(RUNTIMES_${target}-fuchsia_CMAKE_SYSTEM_NAME Fuchsia CACHE STRING "")
   set(RUNTIMES_${target}-fuchsia_UNIX 1 CACHE BOOL "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_SYSTEM_NAME Fuchsia CACHE STRING "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_BUILD_TYPE ${FUCHSIA_RUNTIMES_BUILD_TYPE} CACHE STRING "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_ASM_FLAGS ${FUCHSIA_${target}_C_FLAGS} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_C_FLAGS ${FUCHSIA_${target}_C_FLAGS} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_CXX_FLAGS ${FUCHSIA_${target}_CXX_FLAGS} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_EXE_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_SHARED_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_MODULE_LINKER_FLAGS ${FUCHSIA_${target}_LINKER_FLAGS} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_CMAKE_SYSROOT ${FUCHSIA_${target}_SYSROOT} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_COMPILER_RT_TEST_COMPILER_CFLAGS ${FUCHSIA_${target}_C_FLAGS} CACHE PATH "")
+  set(RUNTIMES_${target}-fuchsia_LLVM_ENABLE_ASSERTIONS ${FUCHSIA_RUNTIMES_ENABLE_ASSERTIONS} CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_LIBUNWIND_USE_COMPILER_RT ON CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_LIBUNWIND_ENABLE_STATIC OFF CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_LIBCXXABI_USE_COMPILER_RT ON CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_LIBCXXABI_USE_LLVM_UNWINDER ON CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_LIBCXXABI_ENABLE_STATIC OFF CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_LIBCXX_USE_COMPILER_RT ON CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_LIBCXX_ENABLE_STATIC OFF CACHE BOOL "")
   set(RUNTIMES_${target}-fuchsia_SANITIZER_USE_COMPILER_RT ON CACHE BOOL "")

clang/cmake/caches/Fuchsia.cmake

set(CLANG_BOOTSTRAP_TARGETS
   test-suite
   test-depends
   llvm-test-depends
   clang-test-depends
   distribution
   install-distribution
   clang CACHE STRING "")
 
-foreach(target x86_64;aarch64)
-  if(FUCHSIA_${target}_SYSROOT)
-    list(APPEND EXTRA_ARGS -DFUCHSIA_${target}_SYSROOT=${FUCHSIA_${target}_SYSROOT})
+get_cmake_property(variableNames VARIABLES)
+foreach(variableName ${variableNames})
+  if(variableName MATCHES "^STAGE2_")
+    string(REPLACE "STAGE2_" "" new_name ${variableName})
+    list(APPEND EXTRA_ARGS "-D${new_name}=${${variableName}}")
   endif()
 endforeach()
 
 # Setup the bootstrap build.
 set(CLANG_ENABLE_BOOTSTRAP ON CACHE BOOL "")
 set(CLANG_BOOTSTRAP_CMAKE_ARGS
   ${EXTRA_ARGS}
   -C ${CMAKE_CURRENT_LIST_DIR}/Fuchsia-stage2.cmake
   CACHE STRING "")