From e9d60c5636a8ba2a9685a741d06641a4b86398f9 Mon Sep 17 00:00:00 2001
From: Dmitry Kalinkin <dmitry.kalinkin@gmail.com>
Date: Fri, 30 Dec 2016 15:58:03 -0500
Subject: [PATCH] libc++3.7: fix to use with modern compilers

Modern compiler will issue a following error whenever '#include <string>'
is done:

/nix/store/yxpwamjdapjcp53mmsdh1j2c9bc26h4k-libc++-3.7.1/include/c++/v1/string:1938:44:
error: 'basic_string<_CharT, _Traits, _Allocator>' is missing exception specification 'noexcept(is_nothrow_copy_constructible<allocator_type>::value)'
basic_string<_CharT, _Traits, _Allocator>::basic_string(const allocator_type& __a)
                                           ^
/nix/store/yxpwamjdapjcp53mmsdh1j2c9bc26h4k-libc++-3.7.1/include/c++/v1/string:1326:40:
note: previous declaration is here
    _LIBCPP_INLINE_VISIBILITY explicit basic_string(const allocator_type& __a)
                                       ^
1 error generated.

This happens because modern clang is more strict about checking
exception specification for forward declaration and definition.

http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/string?r1=242056&r2=242623&diff_format=h
---
 .../compilers/llvm/3.7/libc++/default.nix        |  5 ++++-
 .../compilers/llvm/3.7/libc++/r242056.patch      | 16 ++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 pkgs/development/compilers/llvm/3.7/libc++/r242056.patch

diff --git a/pkgs/development/compilers/llvm/3.7/libc++/default.nix b/pkgs/development/compilers/llvm/3.7/libc++/default.nix
index 62402142a129..1196645b923e 100644
--- a/pkgs/development/compilers/llvm/3.7/libc++/default.nix
+++ b/pkgs/development/compilers/llvm/3.7/libc++/default.nix
@@ -14,7 +14,10 @@ stdenv.mkDerivation rec {
     cmakeFlagsArray=($cmakeFlagsArray -DLIBCXX_CXX_ABI_INCLUDE_PATHS="$NIX_BUILD_TOP/libcxxabi-${version}.src/include")
   '';
 
-  patches = [ ./darwin.patch ];
+  patches = [
+    ./darwin.patch
+    ./r242056.patch
+  ];
 
   buildInputs = [ cmake libcxxabi ] ++ lib.optional stdenv.isDarwin fixDarwinDylibNames;
 
diff --git a/pkgs/development/compilers/llvm/3.7/libc++/r242056.patch b/pkgs/development/compilers/llvm/3.7/libc++/r242056.patch
new file mode 100644
index 000000000000..96245e76653a
--- /dev/null
+++ b/pkgs/development/compilers/llvm/3.7/libc++/r242056.patch
@@ -0,0 +1,16 @@
+--- a/include/string	2015/07/13 20:04:56	242056
++++ b/include/string	2015/07/18 20:40:46	242623
+@@ -1936,7 +1936,12 @@
+ template <class _CharT, class _Traits, class _Allocator>
+ inline _LIBCPP_INLINE_VISIBILITY
+ basic_string<_CharT, _Traits, _Allocator>::basic_string(const allocator_type& __a)
+-    : __r_(__a)
++#if _LIBCPP_STD_VER <= 14
++        _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
++#else
++        _NOEXCEPT
++#endif
++: __r_(__a)
+ {
+ #if _LIBCPP_DEBUG_LEVEL >= 2
+     __get_db()->__insert_c(this);