From 31e79901454264b4e3ad22a207bf5df9d6aef9a5 Mon Sep 17 00:00:00 2001
From: SparkyPotato <noob.sparkypotato@gmail.com>
Date: Wed, 6 Apr 2022 01:32:26 +0530
Subject: [PATCH 1/3] fix Vec leak with 0 capacity

---
 library/alloc/src/raw_vec.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/library/alloc/src/raw_vec.rs b/library/alloc/src/raw_vec.rs
index 0ce2beb63d681..5cf190423e399 100644
--- a/library/alloc/src/raw_vec.rs
+++ b/library/alloc/src/raw_vec.rs
@@ -170,6 +170,13 @@ impl<T, A: Allocator> RawVec<T, A> {
     fn allocate_in(capacity: usize, init: AllocInit, alloc: A) -> Self {
         if mem::size_of::<T>() == 0 {
             Self::new_in(alloc)
+        } else if capacity == 0 {
+            // Don't allocate here because `Drop` will not deallocate when `capacity` is 0.
+            Self {
+                ptr: unsafe { Unique::new_unchecked(NonNull::dangling().as_ptr()) },
+                cap: capacity,
+                alloc,
+            }
         } else {
             // We avoid `unwrap_or_else` here because it bloats the amount of
             // LLVM IR generated.

From 9e9881bcd803390bfbc1e3b1c64ad66330b01103 Mon Sep 17 00:00:00 2001
From: SparkyPotato <noob.sparkypotato@gmail.com>
Date: Wed, 6 Apr 2022 01:36:24 +0530
Subject: [PATCH 2/3] cleanup

---
 library/alloc/src/raw_vec.rs | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/library/alloc/src/raw_vec.rs b/library/alloc/src/raw_vec.rs
index 5cf190423e399..f73b3866c9cb5 100644
--- a/library/alloc/src/raw_vec.rs
+++ b/library/alloc/src/raw_vec.rs
@@ -168,15 +168,9 @@ impl<T, A: Allocator> RawVec<T, A> {
 
     #[cfg(not(no_global_oom_handling))]
     fn allocate_in(capacity: usize, init: AllocInit, alloc: A) -> Self {
-        if mem::size_of::<T>() == 0 {
+		// Don't allocate here because `Drop` will not deallocate when `capacity` is 0.
+        if mem::size_of::<T>() == 0 || capacity == 0 {
             Self::new_in(alloc)
-        } else if capacity == 0 {
-            // Don't allocate here because `Drop` will not deallocate when `capacity` is 0.
-            Self {
-                ptr: unsafe { Unique::new_unchecked(NonNull::dangling().as_ptr()) },
-                cap: capacity,
-                alloc,
-            }
         } else {
             // We avoid `unwrap_or_else` here because it bloats the amount of
             // LLVM IR generated.

From 83f659b4bb2212037ec62028b1979ec31d956fdd Mon Sep 17 00:00:00 2001
From: SparkyPotato <noob.sparkypotato@gmail.com>
Date: Wed, 6 Apr 2022 01:36:46 +0530
Subject: [PATCH 3/3] formatting

---
 library/alloc/src/raw_vec.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/alloc/src/raw_vec.rs b/library/alloc/src/raw_vec.rs
index f73b3866c9cb5..9dbac3c36ffb2 100644
--- a/library/alloc/src/raw_vec.rs
+++ b/library/alloc/src/raw_vec.rs
@@ -168,7 +168,7 @@ impl<T, A: Allocator> RawVec<T, A> {
 
     #[cfg(not(no_global_oom_handling))]
     fn allocate_in(capacity: usize, init: AllocInit, alloc: A) -> Self {
-		// Don't allocate here because `Drop` will not deallocate when `capacity` is 0.
+        // Don't allocate here because `Drop` will not deallocate when `capacity` is 0.
         if mem::size_of::<T>() == 0 || capacity == 0 {
             Self::new_in(alloc)
         } else {