From 7b80a15c6eebc069e593e0f748d3b2c618b239c7 Mon Sep 17 00:00:00 2001
From: Walter Bright <walter@walterbright.com>
Date: Sun, 12 Jun 2016 02:05:59 -0700
Subject: [PATCH] fix unsafe .ptr access in druntime

---
 src/core/internal/string.d |  4 ++--
 src/rt/util/array.d        | 27 +++++++++++++++++----------
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/core/internal/string.d b/src/core/internal/string.d
index cecec37fe3..96f2e580db 100644
--- a/src/core/internal/string.d
+++ b/src/core/internal/string.d
@@ -78,8 +78,8 @@ auto signedToTempString(long value, char[] buf, uint radix) @safe
     if(neg)
     {
         // about to do a slice without a bounds check
-        assert(r.ptr > buf.ptr);
-        r = (() @trusted => (r.ptr-1)[0..r.length+1])();
+        auto trustedSlice() @trusted { assert(r.ptr > buf.ptr); return (r.ptr-1)[0..r.length+1]; }
+        r = trustedSlice();
         r[0] = '-';
     }
     return r;
diff --git a/src/rt/util/array.d b/src/rt/util/array.d
index f299052444..8060338733 100644
--- a/src/rt/util/array.d
+++ b/src/rt/util/array.d
@@ -10,27 +10,28 @@ module rt.util.array;
 
 
 import core.internal.string;
+import core.stdc.stdint;
 
 
 @safe /* pure dmd @@@BUG11461@@@ */ nothrow:
 
-void enforceTypedArraysConformable(T)(in char[] action,
-    in T[] a1, in T[] a2, in bool allowOverlap = false)
+void enforceTypedArraysConformable(T)(const char[] action,
+    const T[] a1, const T[] a2, in bool allowOverlap = false)
 {
     _enforceSameLength(action, a1.length, a2.length);
     if(!allowOverlap)
-        _enforceNoOverlap(action, a1.ptr, a2.ptr, T.sizeof * a1.length);
+        _enforceNoOverlap(action, arrayToPtr(a1), arrayToPtr(a2), T.sizeof * a1.length);
 }
 
-void enforceRawArraysConformable(in char[] action, in size_t elementSize,
-    in void[] a1, in void[] a2, in bool allowOverlap = false)
+void enforceRawArraysConformable(const char[] action, in size_t elementSize,
+    const void[] a1, const void[] a2, in bool allowOverlap = false)
 {
     _enforceSameLength(action, a1.length, a2.length);
     if(!allowOverlap)
-        _enforceNoOverlap(action, a1.ptr, a2.ptr, elementSize * a1.length);
+        _enforceNoOverlap(action, arrayToPtr(a1), arrayToPtr(a2), elementSize * a1.length);
 }
 
-private void _enforceSameLength(in char[] action,
+private void _enforceSameLength(const char[] action,
     in size_t length1, in size_t length2)
 {
     if(length1 == length2)
@@ -46,10 +47,10 @@ private void _enforceSameLength(in char[] action,
     throw new Error(msg);
 }
 
-private void _enforceNoOverlap(in char[] action,
-    in void* ptr1, in void* ptr2, in size_t bytes)
+private void _enforceNoOverlap(const char[] action,
+    uintptr_t ptr1, uintptr_t ptr2, in size_t bytes)
 {
-    const size_t d = ptr1 > ptr2 ? ptr1 - ptr2 : ptr2 - ptr1;
+    const d = ptr1 > ptr2 ? ptr1 - ptr2 : ptr2 - ptr1;
     if(d >= bytes)
         return;
     const overlappedBytes = bytes - d;
@@ -63,3 +64,9 @@ private void _enforceNoOverlap(in char[] action,
     msg ~= bytes.unsignedToTempString(tmpBuff, 10);
     throw new Error(msg);
 }
+
+private uintptr_t arrayToPtr(const void[] array) @trusted
+{
+    // Ok because the user will never dereference the pointer
+    return cast(uintptr_t)array.ptr;
+}