From dae39608bbfe0d0bdea05e041a77df1e3e99e48b Mon Sep 17 00:00:00 2001 From: Eric Fiselier Date: Mon, 16 Jan 2017 21:01:00 +0000 Subject: [PATCH] [libc++] Introduce _LIBCPP_EXTERN_VIS to fix __libcpp_debug_function link errors Summary: On Windows tests that use `_LIBCPP_ASSERT` fail to link because the assertion handler function isn't correctly exported from the libc++ dylib. This patch fixes the dll import/export issues by introducing a new visibility macro `_LIBCPP_EXTERN_VIS` for use on external variables. Reviewers: compnerd, smeenai, EricWF Reviewed By: EricWF Subscribers: cfe-commits Differential Revision: https://reviews.llvm.org/D28728 git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@292158 91177308-0d34-0410-b5e6-96231b3b80d8 --- docs/DesignDocs/VisibilityMacros.rst | 6 ++++++ include/__config | 5 +++++ include/__debug | 2 +- 3 files changed, 12 insertions(+), 1 deletion(-) diff --git a/docs/DesignDocs/VisibilityMacros.rst b/docs/DesignDocs/VisibilityMacros.rst index 7c6f39c44..12c1d56b3 100644 --- a/docs/DesignDocs/VisibilityMacros.rst +++ b/docs/DesignDocs/VisibilityMacros.rst @@ -22,6 +22,12 @@ Visibility Macros Mark a symbol as being exported by the libc++ library. This attribute must be applied to the declaration of all functions exported by the libc++ dylib. +**_LIBCPP_EXTERN_VIS** + Mark a symbol as being exported by the libc++ library. This attribute may + only be applied to objects defined in the libc++ library. On Windows this + macro applies `dllimport`/`dllexport` to the symbol. On all other platforms + this macro has no effect. + **_LIBCPP_OVERRIDABLE_FUNC_VIS** Mark a symbol as being exported by the libc++ library, but allow it to be overridden locally. On non-Windows, this is equivalent to `_LIBCPP_FUNC_VIS`. diff --git a/include/__config b/include/__config index 118e3bde2..d7ecdcfc9 100644 --- a/include/__config +++ b/include/__config @@ -583,6 +583,7 @@ namespace std { #define _LIBCPP_TYPE_VIS _LIBCPP_DLL_VIS #define _LIBCPP_FUNC_VIS _LIBCPP_DLL_VIS +#define _LIBCPP_EXTERN_VIS _LIBCPP_DLL_VIS #define _LIBCPP_EXCEPTION_ABI _LIBCPP_DLL_VIS #define _LIBCPP_HIDDEN #define _LIBCPP_TEMPLATE_VIS @@ -636,6 +637,10 @@ namespace std { # define _LIBCPP_FUNC_VIS_ONLY _LIBCPP_FUNC_VIS #endif +#ifndef _LIBCPP_EXTERN_VIS +# define _LIBCPP_EXTERN_VIS +#endif + #ifndef _LIBCPP_OVERRIDABLE_FUNC_VIS # define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_FUNC_VIS #endif diff --git a/include/__debug b/include/__debug index d95e33931..d01bacdf7 100644 --- a/include/__debug +++ b/include/__debug @@ -74,7 +74,7 @@ typedef void(*__libcpp_debug_function_type)(__libcpp_debug_info const&); /// __libcpp_debug_function - The handler function called when a _LIBCPP_ASSERT /// fails. -extern __libcpp_debug_function_type __libcpp_debug_function; +extern _LIBCPP_EXTERN_VIS __libcpp_debug_function_type __libcpp_debug_function; /// __libcpp_abort_debug_function - A debug handler that aborts when called. _LIBCPP_NORETURN _LIBCPP_FUNC_VIS