Fix configuring and building libc++ w/o an ABI library.

Typically libc++ uses libc++abi or libcxxrt to provide the ABI and runtime bits
of the C++ STL. However we also support building w/o an ABI library entirely.
This patch fixes building libc++ w/o an ABI library (and incorporates the
`~type_info()` fix in D28211).

The main changes in this patch are:

1) Add `-DLIBCXX_CXX_ABI=default` instead of using the empty string to mean "default".
2) Fix CMake bits which treated "none" as "default" on OS X.
3) Teach the source files to respect `-D_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY`.
4) Define ~type_info() when _LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY is defined.

Unfortunately this patch doesn't help clean up the macro mess that we use to
configure for different ABI libraries.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@290839 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -87,13 +87,13 @@ if (NOT LIBCXX_ENABLE_SHARED AND NOT LIBCXX_ENABLE_STATIC)
 endif()
 
 # ABI Library options ---------------------------------------------------------
-set(LIBCXX_CXX_ABI "${LIBCXX_CXX_ABI}" CACHE STRING
+set(LIBCXX_CXX_ABI "default" CACHE STRING
-    "Specify C++ ABI library to use." FORCE)
+    "Specify C++ ABI library to use.")
-set(CXXABIS none libcxxabi libcxxrt libstdc++ libsupc++)
+set(CXXABIS none default libcxxabi libcxxrt libstdc++ libsupc++)
 set_property(CACHE LIBCXX_CXX_ABI PROPERTY STRINGS ;${CXXABIS})
 
 # Setup the default options if LIBCXX_CXX_ABI is not specified.
-if (NOT LIBCXX_CXX_ABI)
+if (LIBCXX_CXX_ABI STREQUAL "default")
   find_path(
     LIBCXX_LIBCXXABI_INCLUDES_INTERNAL
     cxxabi.h
@@ -107,7 +107,7 @@ if (NOT LIBCXX_CXX_ABI)
     set(LIBCXX_CXX_ABI_INCLUDE_PATHS "${LIBCXX_LIBCXXABI_INCLUDES_INTERNAL}")
     set(LIBCXX_CXX_ABI_INTREE 1)
   else()
-    set(LIBCXX_CXX_ABI_LIBNAME "none")
+    set(LIBCXX_CXX_ABI_LIBNAME "default")
   endif()
 else()
   set(LIBCXX_CXX_ABI_LIBNAME "${LIBCXX_CXX_ABI}")
@@ -125,6 +125,7 @@ option(LIBCXX_ENABLE_STATIC_ABI_LIBRARY "Statically link the ABI library" OFF)
 set(ENABLE_LINKER_SCRIPT_DEFAULT_VALUE OFF)
 if (LLVM_HAVE_LINK_VERSION_SCRIPT AND NOT LIBCXX_ENABLE_STATIC_ABI_LIBRARY
       AND NOT LIBCXX_CXX_ABI_LIBNAME STREQUAL "none"
+      AND NOT LIBCXX_CXX_ABI_LIBNAME STREQUAL "default"
       AND PYTHONINTERP_FOUND
       AND LIBCXX_ENABLE_SHARED)
     set(ENABLE_LINKER_SCRIPT_DEFAULT_VALUE ON)

cmake/Modules/HandleLibCXXABI.cmake

@@ -102,7 +102,11 @@ elseif ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "libcxxrt")
   setup_abi_lib("-DLIBCXXRT"
     "cxxrt" "cxxabi.h;unwind.h;unwind-arm.h;unwind-itanium.h" ""
     )
-elseif (NOT "${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "none")
+elseif ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "none")
+  list(APPEND LIBCXX_COMPILE_FLAGS "-D_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY")
+elseif ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "default")
+  # Nothing TODO
+else()
   message(FATAL_ERROR
     "Currently libstdc++, libsupc++, libcxxabi, libcxxrt and none are "
     "supported for c++ abi."

lib/CMakeLists.txt

@@ -34,7 +34,7 @@ add_link_flags_if(LIBCXX_CXX_ABI_LIBRARY_PATH "-L${LIBCXX_CXX_ABI_LIBRARY_PATH}"
 add_library_flags_if(LIBCXX_COVERAGE_LIBRARY "${LIBCXX_COVERAGE_LIBRARY}")
 
 if (APPLE AND (LIBCXX_CXX_ABI_LIBNAME STREQUAL "libcxxabi" OR
-               LIBCXX_CXX_ABI_LIBNAME STREQUAL "none"))
+               LIBCXX_CXX_ABI_LIBNAME STREQUAL "default"))
   set(LIBCXX_OSX_REEXPORT_SYSTEM_ABI_LIBRARY ON)
 endif()
 

lib/abi/CMakeLists.txt

@@ -5,7 +5,7 @@ if (DEFINED TARGET_TRIPLE
     AND EXISTS "${CMAKE_CURRENT_LIST_DIR}/${TARGET_TRIPLE}.abilist"
     AND TARGET cxx_shared
     AND ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "libcxxabi" OR
-         (APPLE AND "${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "none"))
+         (APPLE AND "${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "default"))
     AND NOT LIBCXX_ABI_UNSTABLE
     AND LIBCXX_ABI_VERSION EQUAL "1")
     set(LIBCXX_HAS_ABILIST_CONFIGURATION 1 CACHE INTERNAL "")

src/exception.cpp

@@ -12,7 +12,8 @@
 #include "exception"
 #include "new"
 
-#if defined(__APPLE__) && !defined(LIBCXXRT)
+#if defined(__APPLE__) && !defined(LIBCXXRT) && \
+    !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY)
   #include <cxxabi.h>
 
   using namespace __cxxabiv1;
@@ -106,7 +107,8 @@ bool uncaught_exception() _NOEXCEPT { return uncaught_exceptions() > 0; }
 
 int uncaught_exceptions() _NOEXCEPT
 {
-#if defined(__APPLE__) || defined(_LIBCPPABI_VERSION)
+#if !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY) && \
+    (defined(__APPLE__) || defined(_LIBCPPABI_VERSION))
    // on Darwin, there is a helper function so __cxa_get_globals is private
 # if _LIBCPPABI_VERSION > 1101
     return __cxa_uncaught_exceptions();

src/new.cpp

@@ -13,7 +13,8 @@
 
 #include "new"
 
-#if defined(__APPLE__) && !defined(LIBCXXRT)
+#if defined(__APPLE__) && !defined(LIBCXXRT) && \
+    !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY)
     #include <cxxabi.h>
 
     #ifndef _LIBCPPABI_VERSION
@@ -26,7 +27,8 @@
     #if defined(LIBCXXRT) || defined(LIBCXX_BUILDING_LIBCXXABI)
         #include <cxxabi.h>
     #endif  // defined(LIBCXX_BUILDING_LIBCXXABI)
-    #if !defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__)
+    #if defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY) || \
+        (!defined(_LIBCPPABI_VERSION) && !defined(__GLIBCXX__))
         static std::new_handler __new_handler;
     #endif  // _LIBCPPABI_VERSION
 #endif

src/stdexcept.cpp

@@ -14,7 +14,8 @@
 #include "__refstring"
 
 /* For _LIBCPPABI_VERSION */
-#if defined(LIBCXX_BUILDING_LIBCXXABI) || defined(__APPLE__) || defined(LIBCXXRT)
+#if !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY) && \
+    (defined(LIBCXX_BUILDING_LIBCXXABI) || defined(__APPLE__) || defined(LIBCXXRT))
 #include <cxxabi.h>
 #endif
 

src/typeinfo.cpp

@@ -8,13 +8,19 @@
 //===----------------------------------------------------------------------===//
 #include <stdlib.h>
 
-#if defined(__APPLE__) || defined(LIBCXXRT) ||                                 \
+#if !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY) && \
-    defined(LIBCXX_BUILDING_LIBCXXABI)
+    (defined(__APPLE__) || defined(LIBCXXRT) || defined(LIBCXX_BUILDING_LIBCXXABI))
 #include <cxxabi.h>
 #endif
 
 #include "typeinfo"
 
+#if defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY)
+std::type_info::~type_info()
+{
+}
+#endif
+
 #if !defined(LIBCXXRT) && !defined(_LIBCPPABI_VERSION)
 
 std::bad_cast::bad_cast() _NOEXCEPT
@@ -47,7 +53,7 @@ std::bad_typeid::what() const _NOEXCEPT
   return "std::bad_typeid";
 }
 
-#ifdef __APPLE__
+#if defined(__APPLE__) && !defined(_LIBCPP_BUILDING_HAS_NO_ABI_LIBRARY)
   // On Darwin, the cxa_bad_* functions cannot be in the lower level library
   // because bad_cast and bad_typeid are defined in his higher level library
   void __cxxabiv1::__cxa_bad_typeid()