1 files changed, 39 insertions, 15 deletions

diff --git a/libc/src/__support/fixedvector.h b/libc/src/__support/fixedvector.h
index 7ac0c230f9c5..34601f86dc01 100644
--- a/libc/src/__support/fixedvector.h
+++ b/libc/src/__support/fixedvector.h
@@ -10,9 +10,10 @@
 #define LLVM_LIBC_SRC___SUPPORT_FIXEDVECTOR_H
 
 #include "src/__support/CPP/array.h"
-
 #include "src/__support/CPP/iterator.h"
+#include "src/__support/libc_assert.h"
 #include "src/__support/macros/config.h"
+#include "src/string/memory_utils/inline_memset.h"
 
 namespace LIBC_NAMESPACE_DECL {
 
@@ -23,27 +24,32 @@ template <typename T, size_t CAPACITY> class FixedVector {
   size_t item_count = 0;
 
 public:
-  constexpr FixedVector() = default;
+  LIBC_INLINE constexpr FixedVector() = default;
 
   using iterator = typename cpp::array<T, CAPACITY>::iterator;
-  constexpr FixedVector(iterator begin, iterator end) : store{}, item_count{} {
+  LIBC_INLINE constexpr FixedVector(iterator begin, iterator end)
+      : store{}, item_count{} {
+    LIBC_ASSERT(begin + CAPACITY >= end);
     for (; begin != end; ++begin)
       push_back(*begin);
   }
 
   using const_iterator = typename cpp::array<T, CAPACITY>::const_iterator;
-  constexpr FixedVector(const_iterator begin, const_iterator end)
+  LIBC_INLINE constexpr FixedVector(const_iterator begin, const_iterator end)
       : store{}, item_count{} {
+    LIBC_ASSERT(begin + CAPACITY >= end);
     for (; begin != end; ++begin)
       push_back(*begin);
   }
 
-  constexpr FixedVector(size_t count, const T &value) : store{}, item_count{} {
+  LIBC_INLINE constexpr FixedVector(size_t count, const T &value)
+      : store{}, item_count{} {
+    LIBC_ASSERT(count <= CAPACITY);
     for (size_t i = 0; i < count; ++i)
       push_back(value);
   }
 
-  constexpr bool push_back(const T &obj) {
+  LIBC_INLINE constexpr bool push_back(const T &obj) {
     if (item_count == CAPACITY)
       return false;
     store[item_count] = obj;
@@ -51,27 +57,43 @@ public:
     return true;
   }
 
-  constexpr const T &back() const { return store[item_count - 1]; }
+  LIBC_INLINE constexpr const T &back() const {
+    LIBC_ASSERT(!empty());
+    return store[item_count - 1];
+  }
 
-  constexpr T &back() { return store[item_count - 1]; }
+  LIBC_INLINE constexpr T &back() {
+    LIBC_ASSERT(!empty());
+    return store[item_count - 1];
+  }
 
-  constexpr bool pop_back() {
+  LIBC_INLINE constexpr bool pop_back() {
     if (item_count == 0)
       return false;
+    inline_memset(&store[item_count - 1], 0, sizeof(T));
     --item_count;
     return true;
   }
 
-  constexpr T &operator[](size_t idx) { return store[idx]; }
+  LIBC_INLINE constexpr T &operator[](size_t idx) {
+    LIBC_ASSERT(idx < item_count);
+    return store[idx];
+  }
 
-  constexpr const T &operator[](size_t idx) const { return store[idx]; }
+  LIBC_INLINE constexpr const T &operator[](size_t idx) const {
+    LIBC_ASSERT(idx < item_count);
+    return store[idx];
+  }
 
-  constexpr bool empty() const { return item_count == 0; }
+  LIBC_INLINE constexpr bool empty() const { return item_count == 0; }
 
-  constexpr size_t size() const { return item_count; }
+  LIBC_INLINE constexpr size_t size() const { return item_count; }
 
   // Empties the store for all practical purposes.
-  constexpr void reset() { item_count = 0; }
+  LIBC_INLINE constexpr void reset() {
+    inline_memset(store.data(), 0, sizeof(T) * item_count);
+    item_count = 0;
+  }
 
   // This static method does not free up the resources held by |store|,
   // say by calling `free` or something similar. It just does the equivalent
@@ -81,7 +103,9 @@ public:
   // dynamically allocated storate. So, the `destroy` method like this
   // matches the `destroy` API of those other data structures so that users
   // can easily swap one data structure for the other.
-  static void destroy(FixedVector<T, CAPACITY> *store) { store->reset(); }
+  LIBC_INLINE static void destroy(FixedVector<T, CAPACITY> *store) {
+    store->reset();
+  }
 
   using reverse_iterator = typename cpp::array<T, CAPACITY>::reverse_iterator;
   LIBC_INLINE constexpr reverse_iterator rbegin() {