Revert "[clang][Fuchsia] Add relative-vtables multilib"

This reverts commit fdbd84c.

Reverting due to failing CI builders for Fuchsia's toolchain:
https://luci-milo.appspot.com/p/fuchsia/builders/ci/clang-linux-x64/b8862150211240186992?

Author: PiJoules

clang/cmake/caches/Fuchsia-stage2.cmake

@@ -211,24 +211,14 @@ if(FUCHSIA_SDK)
     set(RUNTIMES_${target}-unknown-fuchsia+asan+noexcept_LIBCXXABI_ENABLE_EXCEPTIONS OFF CACHE BOOL "")
     set(RUNTIMES_${target}-unknown-fuchsia+asan+noexcept_LIBCXX_ENABLE_EXCEPTIONS OFF CACHE BOOL "")
 
-    set(RUNTIMES_${target}-unknown-fuchsia+relative-vtables_LLVM_BUILD_COMPILER_RT OFF CACHE BOOL "")
-    set(RUNTIMES_${target}-unknown-fuchsia+relative-vtables_CMAKE_CXX_FLAGS "${RUNTIMES_${target}-unknown-fuchsia+relative-vtables_CMAKE_CXX_FLAGS} -Xclang -fexperimental-relative-c++-abi-vtables" CACHE STRING "")
-
-    set(RUNTIMES_${target}-unknown-fuchsia+relative-vtables+noexcept_LLVM_BUILD_COMPILER_RT OFF CACHE BOOL "")
-    set(RUNTIMES_${target}-unknown-fuchsia+relative-vtables+noexcept_CMAKE_CXX_FLAGS "${RUNTIMES_${target}-unknown-fuchsia+relative-vtables+noexcept_CMAKE_CXX_FLAGS} -Xclang -fexperimental-relative-c++-abi-vtables" CACHE STRING "")
-    set(RUNTIMES_${target}-unknown-fuchsia+relative-vtables+noexcept_LIBCXXABI_ENABLE_EXCEPTIONS OFF CACHE BOOL "")
-    set(RUNTIMES_${target}-unknown-fuchsia+relative-vtables+noexcept_LIBCXX_ENABLE_EXCEPTIONS OFF CACHE BOOL "")
-
     # Use .build-id link.
     list(APPEND RUNTIME_BUILD_ID_LINK "${target}-unknown-fuchsia")
   endforeach()
 
-  set(LLVM_RUNTIME_MULTILIBS "asan;noexcept;asan+noexcept;relative-vtables;relative-vtables+noexcept" CACHE STRING "")
+  set(LLVM_RUNTIME_MULTILIBS "asan;noexcept;asan+noexcept" CACHE STRING "")
   set(LLVM_RUNTIME_MULTILIB_asan_TARGETS "x86_64-unknown-fuchsia;aarch64-unknown-fuchsia" CACHE STRING "")
   set(LLVM_RUNTIME_MULTILIB_noexcept_TARGETS "x86_64-unknown-fuchsia;aarch64-unknown-fuchsia" CACHE STRING "")
   set(LLVM_RUNTIME_MULTILIB_asan+noexcept_TARGETS "x86_64-unknown-fuchsia;aarch64-unknown-fuchsia" CACHE STRING "")
-  set(LLVM_RUNTIME_MULTILIB_relative-vtables_TARGETS "x86_64-unknown-fuchsia;aarch64-unknown-fuchsia" CACHE STRING "")
-  set(LLVM_RUNTIME_MULTILIB_relative-vtables+noexcept_TARGETS "x86_64-unknown-fuchsia;aarch64-unknown-fuchsia" CACHE STRING "")
 endif()
 
 set(LLVM_BUILTIN_TARGETS "${BUILTIN_TARGETS}" CACHE STRING "")

clang/lib/Driver/ToolChains/Fuchsia.cpp

@@ -210,13 +210,6 @@ Fuchsia::Fuchsia(const Driver &D, const llvm::Triple &Triple,
                           .flag("+fsanitize=address")
                           .flag("-fexceptions")
                           .flag("+fno-exceptions"));
-  // Use the relative vtables ABI.
-  Multilibs.push_back(Multilib("relative-vtables", {}, {}, 4)
-                          .flag("+fexperimental-relative-c++-abi-vtables"));
-  Multilibs.push_back(Multilib("relative-vtables+noexcept", {}, {}, 5)
-                          .flag("+fexperimental-relative-c++-abi-vtables")
-                          .flag("-fexceptions")
-                          .flag("+fno-exceptions"));
   Multilibs.FilterOut([&](const Multilib &M) {
     std::vector<std::string> RD = FilePaths(M);
     return std::all_of(RD.begin(), RD.end(), [&](std::string P) {
@@ -229,13 +222,6 @@ Fuchsia::Fuchsia(const Driver &D, const llvm::Triple &Triple,
       Args.hasFlag(options::OPT_fexceptions, options::OPT_fno_exceptions, true),
       "fexceptions", Flags);
   addMultilibFlag(getSanitizerArgs().needsAsanRt(), "fsanitize=address", Flags);
-
-  addMultilibFlag(
-      Args.hasFlag(options::OPT_fexperimental_relative_cxx_abi_vtables,
-                   options::OPT_fno_experimental_relative_cxx_abi_vtables,
-                   /*default=*/false),
-      "fexperimental-relative-c++-abi-vtables", Flags);
-
   Multilibs.setFilePathsCallback(FilePaths);
 
   if (Multilibs.select(Flags, SelectedMultilib))

clang/test/Driver/Inputs/basic_fuchsia_tree/lib/aarch64-fuchsia/c++/relative-vtables+noexcept/libc++.so

@@ -86,20 +86,8 @@
 // RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
 // RUN:     -fuse-ld=lld 2>&1\
 // RUN:     | FileCheck %s -check-prefixes=CHECK-MULTILIB-X86,CHECK-MULTILIB-ASAN-NOEXCEPT-X86
-// RUN: %clangxx %s -### --target=x86_64-fuchsia -fexperimental-relative-c++-abi-vtables \
-// RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
-// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
-// RUN:     -fuse-ld=lld 2>&1\
-// RUN:     | FileCheck %s -check-prefixes=CHECK-MULTILIB-X86,CHECK-MULTILIB-RELATIVE-VTABLES-X86
-// RUN: %clangxx %s -### --target=x86_64-fuchsia -fexperimental-relative-c++-abi-vtables -fno-exceptions \
-// RUN:     -ccc-install-dir %S/Inputs/basic_fuchsia_tree/bin \
-// RUN:     -resource-dir=%S/Inputs/resource_dir_with_per_target_subdir \
-// RUN:     -fuse-ld=lld 2>&1\
-// RUN:     | FileCheck %s -check-prefixes=CHECK-MULTILIB-X86,CHECK-MULTILIB-RELATIVE-VTABLES-NOEXCEPT-X86
 // CHECK-MULTILIB-X86: "-resource-dir" "[[RESOURCE_DIR:[^"]+]]"
 // CHECK-MULTILIB-ASAN-X86: "-L{{.*}}{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}c++{{/|\\\\}}asan"
 // CHECK-MULTILIB-NOEXCEPT-X86: "-L{{.*}}{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}c++{{/|\\\\}}noexcept"
 // CHECK-MULTILIB-ASAN-NOEXCEPT-X86: "-L{{.*}}{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}c++{{/|\\\\}}asan+noexcept"
-// CHECK-MULTILIB-RELATIVE-VTABLES-X86: "-L{{.*}}{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}c++{{/|\\\\}}relative-vtables"
-// CHECK-MULTILIB-RELATIVE-VTABLES-NOEXCEPT-X86: "-L{{.*}}{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}c++{{/|\\\\}}relative-vtables+noexcept"
 // CHECK-MULTILIB-X86: "-L{{.*}}{{/|\\\\}}..{{/|\\\\}}lib{{/|\\\\}}x86_64-fuchsia{{/|\\\\}}c++"