3 files changed, 44 insertions, 0 deletions
diff --git a/tests/run-make/intrinsic-unreachable/Makefile b/tests/run-make/intrinsic-unreachable/Makefile
new file mode 100644
index 000000000..ff9cc5709
--- /dev/null
+++ b/tests/run-make/intrinsic-unreachable/Makefile
@@ -0,0 +1,12 @@
+include ../tools.mk
+
+# needs-asm-support
+# ignore-windows-msvc
+#
+# Because of Windows exception handling, the code is not necessarily any shorter.
+# https://github.com/llvm-mirror/llvm/commit/64b2297786f7fd6f5fa24cdd4db0298fbf211466
+
+all:
+	$(RUSTC) -O --emit asm exit-ret.rs
+	$(RUSTC) -O --emit asm exit-unreachable.rs
+	test `wc -l < $(TMPDIR)/exit-unreachable.s` -lt `wc -l < $(TMPDIR)/exit-ret.s`
diff --git a/tests/run-make/intrinsic-unreachable/exit-ret.rs b/tests/run-make/intrinsic-unreachable/exit-ret.rs
new file mode 100644
index 000000000..e7b9694d9
--- /dev/null
+++ b/tests/run-make/intrinsic-unreachable/exit-ret.rs
@@ -0,0 +1,14 @@
+#![crate_type="lib"]
+use std::arch::asm;
+
+#[deny(unreachable_code)]
+pub fn exit(n: usize) -> i32 {
+    unsafe {
+        // Pretend this asm is an exit() syscall.
+        asm!("/*{0}*/", in(reg) n);
+    }
+    // This return value is just here to generate some extra code for a return
+    // value, making it easier for the test script to detect whether the
+    // compiler deleted it.
+    42
+}
diff --git a/tests/run-make/intrinsic-unreachable/exit-unreachable.rs b/tests/run-make/intrinsic-unreachable/exit-unreachable.rs
new file mode 100644
index 000000000..ec85db733
--- /dev/null
+++ b/tests/run-make/intrinsic-unreachable/exit-unreachable.rs
@@ -0,0 +1,18 @@
+#![feature(core_intrinsics)]
+#![crate_type="lib"]
+use std::arch::asm;
+
+use std::intrinsics;
+
+#[allow(unreachable_code)]
+pub fn exit(n: usize) -> i32 {
+    unsafe {
+        // Pretend this asm is an exit() syscall.
+        asm!("/*{0}*/", in(reg) n);
+        intrinsics::unreachable()
+    }
+    // This return value is just here to generate some extra code for a return
+    // value, making it easier for the test script to detect whether the
+    // compiler deleted it.
+    42
+}