1 files changed, 19 insertions, 0 deletions
diff --git a/tests/ui/mir/mir_codegen_ssa.rs b/tests/ui/mir/mir_codegen_ssa.rs
new file mode 100644
index 000000000..5e2f10cef
--- /dev/null
+++ b/tests/ui/mir/mir_codegen_ssa.rs
@@ -0,0 +1,19 @@
+// build-pass
+// compile-flags: --crate-type=lib
+#![feature(custom_mir, core_intrinsics)]
+use std::intrinsics::mir::*;
+
+#[custom_mir(dialect = "runtime", phase = "optimized")]
+pub fn f(a: u32) -> u32 {
+    mir!(
+        let x: u32;
+        {
+            // Previously code generation failed with ICE "use of .. before def ..." because the
+            // definition of x was incorrectly identified as dominating the use of x located in the
+            // same statement:
+            x = x + a;
+            RET = x;
+            Return()
+        }
+    )
+}