Enable building the LLVM Hexagon target

Author: michaelwu

src/bootstrap/config.toml.example

@@ -51,7 +51,7 @@
 # support. You'll need to write a target specification at least, and most
 # likely, teach rustc about the C ABI of the target. Get in touch with the
 # Rust team and file an issue if you need assistance in porting!
-#targets = "X86;ARM;AArch64;Mips;PowerPC;SystemZ;JSBackend;MSP430;Sparc;NVPTX"
+#targets = "X86;ARM;AArch64;Mips;PowerPC;SystemZ;JSBackend;MSP430;Sparc;NVPTX;Hexagon"
 
 # Cap the number of parallel linker invocations when compiling LLVM.
 # This can be useful when building LLVM with debug info, which significantly

src/bootstrap/native.rs

@@ -81,7 +81,7 @@ pub fn llvm(build: &Build, target: &str) {
     // NOTE: remember to also update `config.toml.example` when changing the defaults!
     let llvm_targets = match build.config.llvm_targets {
         Some(ref s) => s,
-        None => "X86;ARM;AArch64;Mips;PowerPC;SystemZ;JSBackend;MSP430;Sparc;NVPTX",
+        None => "X86;ARM;AArch64;Mips;PowerPC;SystemZ;JSBackend;MSP430;Sparc;NVPTX;Hexagon",
     };
 
     let assertions = if build.config.llvm_assertions {"ON"} else {"OFF"};