diff --git a/.gitignore b/.gitignore
index e69de29..be368c4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1 @@
+/libcxx-3.8.0.src.tar.xz
diff --git a/libcxx.spec b/libcxx.spec
new file mode 100644
index 0000000..0463b70
--- /dev/null
+++ b/libcxx.spec
@@ -0,0 +1,97 @@
+# If you need to bootstrap this, turn this on.
+# Otherwise, you have a loop with libcxxabi
+%global bootstrap 1
+
+Name:		libcxx
+Version:	3.8.0
+Release:	3%{?dist}
+Summary:	C++ standard library targeting C++11
+License:	MIT or NCSA
+URL:		http://libcxx.llvm.org/
+Source0:	http://llvm.org/releases/%{version}/libcxx-%{version}.src.tar.xz
+BuildRequires:	clang llvm-devel cmake
+%if %{bootstrap} < 1
+BuildRequires:	libcxxabi-devel
+%endif
+# PPC64 (on EL7) doesn't like this code.
+# /builddir/build/BUILD/libcxx-3.8.0.src/include/thread:431:73: error: '(9.223372036854775807e+18 / 1.0e+9)' is not a constant expression
+# _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max();
+ExcludeArch:	ppc64 ppc64le
+
+%description
+libc++ is a new implementation of the C++ standard library, targeting C++11.
+
+%package devel
+Summary:	Headers and libraries for libcxx devel
+Requires:	%{name}%{?_isa} = %{version}-%{release}
+%if %{bootstrap} < 1
+Requires:	libcxxabi-devel
+%endif
+
+
+%description devel
+%{summary}.
+
+%prep
+%setup -q -n %{name}-%{version}.src
+
+%build
+mkdir _build
+cd _build
+# Clang in older releases than f24 can't build this code without crashing.
+# So, we use gcc there. But the really old version in RHEL 6 works. Huh.
+%cmake .. \
+%if 0%{?rhel} == 6
+	-DCMAKE_C_COMPILER=/usr/bin/clang \
+	-DCMAKE_CXX_COMPILER=/usr/bin/clang++ \
+%else
+%if 0%{?fedora} >= 24
+	-DCMAKE_C_COMPILER=/usr/bin/clang \
+	-DCMAKE_CXX_COMPILER=/usr/bin/clang++ \
+%else
+	-DCMAKE_C_COMPILER=/usr/bin/gcc \
+	-DCMAKE_CXX_COMPILER=/usr/bin/g++ \
+%endif
+%endif
+	-DLLVM_CONFIG=%{_bindir}/llvm-config \
+%if %{bootstrap} < 1
+	-DLIBCXX_CXX_ABI=libcxxabi \
+	-DLIBCXX_CXX_ABI_INCLUDE_PATHS=%{_includedir} \
+%endif
+%if %{__isa_bits} == 64
+	-DLIBCXX_LIBDIR_SUFFIX:STRING=64 \
+%endif
+	-DCMAKE_BUILD_TYPE=RelWithDebInfo
+
+
+make %{?_smp_mflags}
+
+%install
+cd _build
+make install DESTDIR=%{buildroot}
+
+%post -p /sbin/ldconfig
+
+%postun -p /sbin/ldconfig
+
+%files
+%license LICENSE.TXT
+%doc CREDITS.TXT TODO.TXT
+%{_libdir}/libc++.so.*
+
+%files devel
+%{_includedir}/c++/
+%{_libdir}/libc++.so
+
+%changelog
+* Thu May 19 2016 Tom Callaway <spot@fedoraproject.org> - 3.8.0-3
+- use gcc on el7, fedora < 24. use clang on el6 and f24+
+  MAGIC.
+- bootstrap on
+
+* Tue May 3 2016 Tom Callaway <spot@fedoraproject.org> - 3.8.0-2
+- bootstrap off
+
+* Tue May 3 2016 Tom Callaway <spot@fedoraproject.org> - 3.8.0-1
+- initial package
+- bootstrap on
diff --git a/sources b/sources
index e69de29..7858a06 100644
--- a/sources
+++ b/sources
@@ -0,0 +1 @@
+d6e0bdbbee39f7907ad74fd56d03b88a  libcxx-3.8.0.src.tar.xz