From 297ec32b86753d1b90e250d92bec0fc2f5d0a634 Mon Sep 17 00:00:00 2001
From: Nico Weber <nicolasweber@gmx.de>
Date: Sun, 29 Apr 2018 23:05:11 +0000
Subject: [PATCH] Move _LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS macro
 to build system

_LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS is currently used to
bring back std::unexpected, which is removed in C++17, but still needed
for libc++abi for backward compatibility.

This macro used to define in cxa_exception.cpp only, but actually
needed for all sources that touches exceptions.
So, a build-system-level macro is better fit to define this macro.

https://reviews.llvm.org/D46056
Patch from Taiju Tsuiku <tzik@chromium.org>!

llvm-svn: 331150
---
 libcxxabi/CMakeLists.txt                       | 4 ++++
 libcxxabi/src/cxa_exception.cpp                | 2 --
 libcxxabi/test/test_exception_storage.pass.cpp | 5 -----
 3 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
index 4b1f151..1488737 100644
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -387,6 +387,10 @@ endif()
 # Prevent libc++abi from having library dependencies on libc++
 add_definitions(-D_LIBCPP_DISABLE_EXTERN_TEMPLATE)
 
+# Bring back `std::unexpected`, which is removed in C++17, to support
+# pre-C++17.
+add_definitions(-D_LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS)
+
 if (MSVC)
   add_definitions(-D_CRT_SECURE_NO_WARNINGS)
 endif()
diff --git a/libcxxabi/src/cxa_exception.cpp b/libcxxabi/src/cxa_exception.cpp
index 5c32a15..397427a 100644
--- a/libcxxabi/src/cxa_exception.cpp
+++ b/libcxxabi/src/cxa_exception.cpp
@@ -11,8 +11,6 @@
 //  
 //===----------------------------------------------------------------------===//
 
-#define _LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS
-
 #include "cxxabi.h"
 
 #include <exception>        // for std::terminate
diff --git a/libcxxabi/test/test_exception_storage.pass.cpp b/libcxxabi/test/test_exception_storage.pass.cpp
index 49c9b5d..ef2524f 100644
--- a/libcxxabi/test/test_exception_storage.pass.cpp
+++ b/libcxxabi/test/test_exception_storage.pass.cpp
@@ -7,11 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// FIXME: cxa_exception.hpp directly references `std::unexpected` and friends.
-// This breaks this test when compiled in C++17. For now fix this by manually
-// re-enabling the STL functions.
-#define _LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS
-
 #include <cstdlib>
 #include <algorithm>
 #include <iostream>
-- 
2.7.4