From b4f675fe150afaa577d6a41d6013ca33d932bd57 Mon Sep 17 00:00:00 2001
From: Jack Stouffer <jack@jackstouffer.com>
Date: Thu, 5 Apr 2018 09:40:02 -0400
Subject: [PATCH] Work On Issue 18693 - Remove rndtonl from std.math

---
 .dscanner.ini                   |  1 -
 changelog/rndtonl-deprecated.dd |  6 ++++++
 std/math.d                      | 38 ++++++++++++++++++++++-----------
 3 files changed, 31 insertions(+), 14 deletions(-)
 create mode 100644 changelog/rndtonl-deprecated.dd

diff --git a/.dscanner.ini b/.dscanner.ini
index 2391b7da59b..0c1ba1daa98 100644
--- a/.dscanner.ini
+++ b/.dscanner.ini
@@ -252,7 +252,6 @@ has_public_example="-etc.c.curl,\
 -std.internal.scopebuffer,\
 -std.internal.test.dummyrange,\
 -std.json,\
--std.math,\
 -std.mathspecial,\
 -std.mmfile,\
 -std.net.curl,\
diff --git a/changelog/rndtonl-deprecated.dd b/changelog/rndtonl-deprecated.dd
new file mode 100644
index 00000000000..8b6ae6140c8
--- /dev/null
+++ b/changelog/rndtonl-deprecated.dd
@@ -0,0 +1,6 @@
+std.math.rndtonl has been deprecated
+
+$(REF rndtonl, std, math) is a rounding function only available when using the
+Digital Mars C Runtime on Windows. As this function is not cross-platform, it
+has been deprecated, and will be removed on version 2.089. Please use
+$(REF round, std, math) instead.
diff --git a/std/math.d b/std/math.d
index 88ffeb5069f..612ff877b75 100644
--- a/std/math.d
+++ b/std/math.d
@@ -1804,22 +1804,34 @@ long rndtol(float x) @safe pure nothrow @nogc { return rndtol(cast(real) x); }
     assert(prndtol != null);
 }
 
-/*****************************************
- * Returns x rounded to a long value using the FE_TONEAREST rounding mode.
- * If the integer value of x is
- * greater than long.max, the result is
- * indeterminate.
+/**
+$(RED Deprecated. Please use $(LREF round) instead.)
+
+Returns `x` rounded to a `long` value using the `FE_TONEAREST` rounding mode.
+If the integer value of `x` is greater than `long.max`, the result is
+indeterminate.
+
+Only works with the Digital Mars C Runtime.
+
+Params:
+    x = the number to round
+Returns:
+    `x` rounded to an integer value
  */
+deprecated("rndtonl is to be removed by 2.089. Please use round instead")
 extern (C) real rndtonl(real x);
 
-// issue 18693
-//@safe unittest
-//{
-//    assert(rndtol(1.0) == 1.0);
-//    assert(rndtol(1.2) == 1.0);
-//    assert(rndtol(1.7) == 2.0);
-//    assert(rndtol(1.0001) == 1.0);
-//}
+///
+deprecated @system unittest
+{
+    version(CRuntime_DigitalMars)
+    {
+        assert(rndtonl(1.0) is -real.nan);
+        assert(rndtonl(1.2) is -real.nan);
+        assert(rndtonl(1.7) is -real.nan);
+        assert(rndtonl(1.0001) is -real.nan);
+    }
+}
 
 /***************************************
  * Compute square root of x.