From 78f425744f2809924844307bdece80bc935b2af7 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Sun, 28 Oct 2018 08:51:47 -0700
Subject: [PATCH] Don't pass 0-length mallocs to system allocator

Part of the unsafe contract!
---
 src/lib.rs | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 1c5ce6ea..4160a89c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -827,9 +827,13 @@ pub mod __rt {
             let align = mem::align_of::<usize>();
             if let Ok(layout) = Layout::from_size_align(size, align) {
                 unsafe {
-                    let ptr = alloc(layout);
-                    if !ptr.is_null() {
-                        return ptr
+                    if layout.size() > 0 {
+                        let ptr = alloc(layout);
+                        if !ptr.is_null() {
+                            return ptr
+                        }
+                    } else {
+                        return align as *mut u8
                     }
                 }
             }