Add SIZEOF_MEMBER.
Bug: N/A
Test: ran tests
Change-Id: Icb7e8ae83d242c867b71a990b08eb1a62ed1482c
diff --git a/include/android-base/macros.h b/include/android-base/macros.h
index 25f2ff4..fd6efb2 100644
--- a/include/android-base/macros.h
+++ b/include/android-base/macros.h
@@ -20,6 +20,8 @@
#include <stddef.h> // for size_t
#include <unistd.h> // for TEMP_FAILURE_RETRY
+#include <utility>
+
// bionic and glibc both have TEMP_FAILURE_RETRY, but eg Mac OS' libc doesn't.
#ifndef TEMP_FAILURE_RETRY
#define TEMP_FAILURE_RETRY(exp) \
@@ -114,6 +116,8 @@
((sizeof(a) / sizeof(*(a))) / \
static_cast<size_t>(!(sizeof(a) % sizeof(*(a)))))
+#define SIZEOF_MEMBER(t, f) sizeof(std::declval<t>().f)
+
// Changing this definition will cause you a lot of pain. A majority of
// vendor code defines LIKELY and UNLIKELY this way, and includes
// this header through an indirect path.