Add linking patch

PKGBUILD

@@ -8,7 +8,7 @@
 
 pkgname=nix
 pkgver=2.3.1
-pkgrel=1
+pkgrel=2
 pkgdesc="A purely functional package manager"
 arch=('i686' 'x86_64' 'armv7h')
 url="https://nixos.org/nix"
@@ -17,16 +17,19 @@ depends=('gc' 'libsodium' 'boost' 'brotli' 'editline')
 optdepends=('archlinux-nix: tools to help with setup of Nix')
 makedepends=('bzip2' 'openssl')
 install=nix.install
-source=("https://nixos.org/releases/nix/nix-$pkgver/nix-$pkgver.tar.xz")
-sha256sums=('bb6578e9f20eebab6d78469ecc59c450ac54f276e5a86a882015d98fecb1bc7b')
+source=("https://nixos.org/releases/nix/nix-$pkgver/nix-$pkgver.tar.xz"
+        'ldflags.patch')
+sha256sums=('bb6578e9f20eebab6d78469ecc59c450ac54f276e5a86a882015d98fecb1bc7b'
+            '42350237d98785b30b0ee099405f2f1f7412f8a816162c22bd232ed3dbbe0305')
 
 prepare() {
   cd "$pkgname-$pkgver"
+  patch --forward --strip=1 --input="${srcdir}/ldflags.patch"
 }
 
 build () {
   cd "$pkgname-$pkgver"
-  ./configure --prefix=/usr \
+  CXXFLAGS='-D_GLIBCXX_USE_CXX11_ABI=0' ./configure --prefix=/usr \
               --libexecdir="/usr/lib/$pkgname" \
               --sysconfdir=/etc \
               --enable-gc