auto merge of #9491 : thestinger/rust/noreturn, r=huonw

Closes #9317
rust-lang · Sep 25, 2013 · 5375cf8 · 5375cf8
2 parents 797a373 + e76bfae
commit 5375cf8
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs
@@ -220,6 +220,12 @@ pub fn decl_rust_fn(ccx: &mut CrateContext, inputs: &[ty::t], output: ty::t,
     let llfn = decl_cdecl_fn(ccx.llmod, name, llfty);
 
     match ty::get(output).sty {
+        // functions returning bottom may unwind, but can never return normally
+        ty::ty_bot => {
+            unsafe {
+                llvm::LLVMAddFunctionAttr(llfn, lib::llvm::NoReturnAttribute as c_uint)
+            }
+        }
         // `~` pointer return values never alias because ownership is transferred
         ty::ty_uniq(*) |
         ty::ty_evec(_, ty::vstore_uniq) => {