From e7e3bf4f5f3509148d030d3af31b2e4555632e7f Mon Sep 17 00:00:00 2001
From: Jordan Maples <jomaples@microsoft.com>
Date: Mon, 14 Sep 2020 15:50:46 -0700
Subject: [PATCH] add what to narrowing_error

---
 include/gsl/gsl_narrow | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/gsl/gsl_narrow b/include/gsl/gsl_narrow
index 7027b58..cec25a1 100644
--- a/include/gsl/gsl_narrow
+++ b/include/gsl/gsl_narrow
@@ -22,6 +22,10 @@ namespace gsl
 {
 struct narrowing_error : public std::exception
 {
+    const char* what() const noexcept override
+    {
+        return "narrowing_error";
+    }
 };
 
 // narrow() : a checked version of narrow_cast() that throws if the cast changed the value