rust-llvm-native: build LLVM in its own recipe

rust takes a painfully long time to build.  A non-trivial part of that
is building LLVM.  Fortuitiously, the LLVM component is common between
the -native compiler and all variants of the -cross compiler.  That
means we can build it once, and reuse the output for any flavor of rust.
That saves build time, and it utilizes bitbake's sstate more
efficiently.  It's win/win!

recipes/rust/rust-llvm-native_1.1.0.bb

@@ -0,0 +1,27 @@
+SUMMARY = "LLVM compiler framework (packaged with rust)"
+LICENSE = "NCSA"
+
+LIC_FILES_CHKSUM = "file://LICENSE.TXT;md5=47e311aa9caedd1b3abf098bd7814d1d"
+
+# 1.1.0
+require rust-release.inc
+SRC_URI[rust.md5sum] = "5f2f923f8d1c77a55721d1f0813a158a"
+SRC_URI[rust.sha256sum] = "cb09f443b37ec1b81fe73c04eb413f9f656859cf7d00bc5088008cbc2a63fa8a"
+
+S = "${WORKDIR}/rustc-${PV}/src/llvm"
+
+inherit autotools
+inherit native
+
+EXTRA_OECONF += "--enable-targets=x86,x86_64,arm,aarch64,mips,powerpc"
+EXTRA_OECONF += "--enable-optimized"
+EXTRA_OECONF += "--disable-bindings"
+
+do_install_append () {
+	cd ${D}${bindir}
+	ln -s *-llc llc
+	for i in *-llvm-*; do
+		link=$(echo $i | sed -e 's/.*-llvm-\(.*\)/\1/')
+		ln -s $i llvm-$link
+	done
+}

recipes/rust/rust-release.inc

@@ -3,5 +3,4 @@ SRC_URI = "\
 "
 
 S = "${WORKDIR}/rustc-${PV}"
-require rust.inc
 

recipes/rust/rust_1.1.0.bb

@@ -1,5 +1,6 @@
 # 1.1.0
 require rust-release.inc
+require rust.inc
 SRC_URI[rust.md5sum] = "5f2f923f8d1c77a55721d1f0813a158a"
 SRC_URI[rust.sha256sum] = "cb09f443b37ec1b81fe73c04eb413f9f656859cf7d00bc5088008cbc2a63fa8a"