From 42e0c8c0a1cabb24b48f56470aea1656a47f9cc7 Mon Sep 17 00:00:00 2001
From: gnzlbg <gonzalobg88@gmail.com>
Date: Wed, 10 Jul 2019 12:59:36 +0200
Subject: [PATCH] Add FMA tests that cause it to segfault

---
 .../compiler-builtins/libm/src/math/fma.rs    | 19 +++++++++++++++++++
 library/compiler-builtins/libm/tests/unit.rs  | 19 +++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 library/compiler-builtins/libm/tests/unit.rs

diff --git a/library/compiler-builtins/libm/src/math/fma.rs b/library/compiler-builtins/libm/src/math/fma.rs
index 07d90f8b727d..6d4471a9a04f 100644
--- a/library/compiler-builtins/libm/src/math/fma.rs
+++ b/library/compiler-builtins/libm/src/math/fma.rs
@@ -205,3 +205,22 @@ pub fn fma(x: f64, y: f64, z: f64) -> f64 {
     }
     scalbn(r, e)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn fma_segfault() {
+        // These two inputs cause fma to segfault on release due to overflow:
+        assert_eq!(
+            fma(
+                -0.0000000000000002220446049250313,
+                -0.0000000000000002220446049250313,
+                -0.0000000000000002220446049250313
+            ),
+            -0.00000000000000022204460492503126,
+        );
+
+        assert_eq!(fma(-0.992, -0.992, -0.992), -0.00793599999988632,);
+    }
+}
diff --git a/library/compiler-builtins/libm/tests/unit.rs b/library/compiler-builtins/libm/tests/unit.rs
new file mode 100644
index 000000000000..4e7002817a64
--- /dev/null
+++ b/library/compiler-builtins/libm/tests/unit.rs
@@ -0,0 +1,19 @@
+use libm::*;
+
+#[test]
+fn fma_segfault() {
+    // These two inputs cause fma to segfault on release due to overflow:
+    assert_eq!(
+        fma(
+            -0.0000000000000002220446049250313,
+            -0.0000000000000002220446049250313,
+            -0.0000000000000002220446049250313
+        ),
+        -0.00000000000000022204460492503126,
+    );
+
+    assert_eq!(
+        fma(-0.992, -0.992, -0.992),
+        -0.00793599999988632,
+    );
+}