From 5fae81e48b3a0a513f8b56e157948f149987977d Mon Sep 17 00:00:00 2001
From: Aaron Clarke <aaclarke@google.com>
Date: Tue, 30 Aug 2022 10:13:28 -0700
Subject: [PATCH] allowed copies of size zero

---
 fml/mapping.h            | 2 +-
 fml/mapping_unittests.cc | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/fml/mapping.h b/fml/mapping.h
index 3bf50841cd130..c6fe0151eff79 100644
--- a/fml/mapping.h
+++ b/fml/mapping.h
@@ -160,7 +160,7 @@ class MallocMapping final : public Mapping {
   /// for `uint8_t` and `char`.
   template <typename T>
   static MallocMapping Copy(const T* begin, const T* end) {
-    FML_DCHECK(end > begin);
+    FML_DCHECK(end >= begin);
     size_t length = end - begin;
     return Copy(begin, length);
   }
diff --git a/fml/mapping_unittests.cc b/fml/mapping_unittests.cc
index 7dc397dbde14e..f0b2a992d18ca 100644
--- a/fml/mapping_unittests.cc
+++ b/fml/mapping_unittests.cc
@@ -60,4 +60,10 @@ TEST(MallocMapping, IsDontNeedSafe) {
   ASSERT_FALSE(mapping.IsDontNeedSafe());
 }
 
+TEST(MallocMapping, CopySizeZero) {
+  char ch = 'a';
+  MallocMapping mapping = MallocMapping::Copy(&ch, &ch);
+  ASSERT_EQ(0u, mapping.GetSize());
+}
+
 }  // namespace fml