[libc++abi] Default to DLL annotations on Windows

`__declspec(dllexport)` and `__declspec(dllimport)` should only be used
when building libc++abi as a DLL, but that's the more common use case,
so default to adding the annotations and add an option to opt out.

Similar to r282449, which made the corresponding change for libc++.

Differential Revision: https://reviews.llvm.org/D24945

llvm-svn: 282470

diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
index e1487b3..a33cf48 100644 (file)
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -249,6 +249,15 @@ if (LIBCXXABI_USE_COMPILER_RT)
   list(APPEND LIBCXXABI_LINK_FLAGS "-rtlib=compiler-rt")
 endif()
 
+# Let the library headers know they are currently being used to build the
+# library.
+add_definitions(-D_LIBCXXABI_BUILDING_LIBRARY)
+
+# Disable DLL annotations on Windows for static builds.
+if (WIN32 AND LIBCXXABI_ENABLE_STATIC AND NOT LIBCXXABI_ENABLE_SHARED)
+  add_definitions(-D_LIBCXXABI_DISABLE_DLL_IMPORT_EXPORT)
+endif()
+
 append_if(LIBCXXABI_COMPILE_FLAGS LIBCXXABI_HAS_WERROR_FLAG -Werror=return-type)
 
 # Get warning flags
@@ -333,7 +342,6 @@ if (LIBCXXABI_HAS_PTHREAD_API)
   add_definitions(-D_LIBCPP_HAS_THREAD_API_PTHREAD)
 endif()
 
-# This is the _ONLY_ place where add_definitions is called.
 if (MSVC)
   add_definitions(-D_CRT_SECURE_NO_WARNINGS)
 endif()

diff --git a/libcxxabi/include/__cxxabi_config.h b/libcxxabi/include/__cxxabi_config.h
index 61555f1..0e7106e 100644 (file)
--- a/libcxxabi/include/__cxxabi_config.h
+++ b/libcxxabi/include/__cxxabi_config.h
@@ -21,8 +21,13 @@
 #define __has_attribute(_attribute_) 0
 #endif
 
-#if defined(_LIBCXXABI_DLL)
- #if defined(cxxabi_EXPORTS)
+#if defined(_WIN32)
+ #if defined(_LIBCXXABI_DISABLE_DLL_IMPORT_EXPORT)
+  #define _LIBCXXABI_HIDDEN
+  #define _LIBCXXABI_DATA_VIS
+  #define _LIBCXXABI_FUNC_VIS
+  #define _LIBCXXABI_TYPE_VIS
+ #elif defined(_LIBCXXABI_BUILDING_LIBRARY)
   #define _LIBCXXABI_HIDDEN
   #define _LIBCXXABI_DATA_VIS __declspec(dllexport)
   #define _LIBCXXABI_FUNC_VIS __declspec(dllexport)