# Backport of abseil/abseil-cpp 0784689a65b4ea1329fbc5174b8a57c88ec796a9.
# Adapted to 20250814.1: prefer Clang 23 lifetime_capture_by_this, retain older compiler fallback.
diff --git a/absl/base/attributes.h b/absl/base/attributes.h
--- a/absl/base/attributes.h
+++ b/absl/base/attributes.h
@@ -911,6 +911,23 @@
 #define ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(Owner)
 #endif
 
+// Internal attribute; name and documentation TBD.
+//
+// See the upstream documentation:
+// https://clang.llvm.org/docs/AttributeReference.html#lifetime_capture_by_this
+//
+// Note: ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this) is deprecated. Use
+// ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS instead.
+#if ABSL_HAVE_CPP_ATTRIBUTE(clang::lifetime_capture_by_this)
+#define ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS \
+  [[clang::lifetime_capture_by_this]]
+#elif ABSL_HAVE_CPP_ATTRIBUTE(clang::lifetime_capture_by)
+#define ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS \
+  ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this)
+#else
+#define ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS
+#endif
+
 // ABSL_ATTRIBUTE_VIEW indicates that a type is solely a "view" of data that it
 // points to, similarly to a span, string_view, or other non-owning reference
 // type.
diff --git a/absl/base/internal/spinlock.h b/absl/base/internal/spinlock.h
--- a/absl/base/internal/spinlock.h
+++ b/absl/base/internal/spinlock.h
@@ -242,1 +242,1 @@
-      SpinLock& l ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+      SpinLock& l ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
diff --git a/absl/container/internal/btree_container.h b/absl/container/internal/btree_container.h
--- a/absl/container/internal/btree_container.h
+++ b/absl/container/internal/btree_container.h
@@ -508,1 +508,1 @@
-          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this)),                        \
+          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS),                        \
@@ -510,1 +510,1 @@
-          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this)))                        \
+          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS))                        \
@@ -610,1 +610,1 @@
-          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this)),                          \
+          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS),                          \
@@ -637,1 +637,1 @@
-      const key_arg<K> &k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+      const key_arg<K> &k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -646,2 +646,1 @@
-  mapped_type &operator[](key_arg<K> &&k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(
-      this)) ABSL_ATTRIBUTE_LIFETIME_BOUND {
+  mapped_type &operator[](key_arg<K> &&k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS) ABSL_ATTRIBUTE_LIFETIME_BOUND {
diff --git a/absl/container/internal/raw_hash_map.h b/absl/container/internal/raw_hash_map.h
--- a/absl/container/internal/raw_hash_map.h
+++ b/absl/container/internal/raw_hash_map.h
@@ -117,1 +117,1 @@
-          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this)),                          \
+          ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS),                          \
@@ -118,2 +118,1 @@
-      V VQual v ABSL_INTERNAL_IF_##VValue(ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY( \
-          this))) ABSL_ATTRIBUTE_LIFETIME_BOUND {                              \
+      V VQual v ABSL_INTERNAL_IF_##VValue(ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)) ABSL_ATTRIBUTE_LIFETIME_BOUND {                              \
@@ -216,1 +215,1 @@
-      key_arg<K> &&k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+      key_arg<K> &&k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,
@@ -235,1 +234,1 @@
-      const key_arg<K> &k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+      const key_arg<K> &k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,
@@ -249,1 +248,1 @@
-                       key_arg<K> &&k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+                       key_arg<K> &&k ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,
@@ -265,1 +264,1 @@
-                           ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+                           ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,
@@ -305,1 +304,1 @@
-      key_arg<K> &&key ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+      key_arg<K> &&key ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -322,1 +321,1 @@
-      const key_arg<K> &key ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+      const key_arg<K> &key ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
diff --git a/absl/container/internal/raw_hash_set.h b/absl/container/internal/raw_hash_set.h
--- a/absl/container/internal/raw_hash_set.h
+++ b/absl/container/internal/raw_hash_set.h
@@ -2428,1 +2428,1 @@
-      T&& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+      T&& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -2457,1 +2457,1 @@
-      const T& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+      const T& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -2477,1 +2477,1 @@
-      init_type&& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+      init_type&& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -2499,1 +2499,1 @@
-                  T&& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+                  T&& value ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
diff --git a/absl/status/statusor.h b/absl/status/statusor.h
--- a/absl/status/statusor.h
+++ b/absl/status/statusor.h
@@ -408,1 +408,1 @@
-  StatusOr& operator=(U&& v ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this)) {
+  StatusOr& operator=(U&& v ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS) {
diff --git a/absl/synchronization/mutex.h b/absl/synchronization/mutex.h
--- a/absl/synchronization/mutex.h
+++ b/absl/synchronization/mutex.h
@@ -604,1 +604,1 @@
-  explicit MutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+  explicit MutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -619,1 +619,1 @@
-  explicit MutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+  explicit MutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,
@@ -646,1 +646,1 @@
-  explicit ReaderMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+  explicit ReaderMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -655,1 +655,1 @@
-  explicit ReaderMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+  explicit ReaderMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,
@@ -682,1 +682,1 @@
-  explicit WriterMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this))
+  explicit WriterMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS)
@@ -692,1 +692,1 @@
-  explicit WriterMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+  explicit WriterMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,
@@ -1096,2 +1096,1 @@
-  explicit ReleasableMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(
-      this)) ABSL_EXCLUSIVE_LOCK_FUNCTION(mu)
+  explicit ReleasableMutexLock(Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS) ABSL_EXCLUSIVE_LOCK_FUNCTION(mu)
@@ -1107,1 +1106,1 @@
-      Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY(this),
+      Mutex& mu ABSL_INTERNAL_ATTRIBUTE_CAPTURED_BY_THIS,