Copy the M_THREAD_DISABLE_MEM_INIT constant value into malloc.h.
This will allow platform and application developers to use it.
Bug: 163630045
Change-Id: If9a361cb97aaf62d3fa124b60f64d51d609af48d
diff --git a/libc/include/malloc.h b/libc/include/malloc.h
index 833fa59..a237254 100644
--- a/libc/include/malloc.h
+++ b/libc/include/malloc.h
@@ -170,6 +170,16 @@
* Available since API level 28.
*/
#define M_PURGE (-101)
+/*
+ * mallopt() option for per-thread memory initialization tuning.
+ * The value argument should be one of:
+ * 1: Disable automatic heap initialization and, where possible, memory tagging,
+ * on this thread.
+ * 0: Normal behavior.
+ *
+ * Available since API level 31.
+ */
+#define M_THREAD_DISABLE_MEM_INIT (-103)
/**
* mallopt() option to set the maximum number of items in the secondary
* cache of the scudo allocator.
diff --git a/tests/malloc_test.cpp b/tests/malloc_test.cpp
index 55bd149..d692cf9 100644
--- a/tests/malloc_test.cpp
+++ b/tests/malloc_test.cpp
@@ -84,6 +84,24 @@
free(ptr);
}
+TEST(malloc, calloc_mem_init_disabled) {
+#if defined(__BIONIC__)
+ // calloc should still zero memory if mem-init is disabled.
+ // With jemalloc the mallopts will fail but that shouldn't affect the
+ // execution of the test.
+ mallopt(M_THREAD_DISABLE_MEM_INIT, 1);
+ size_t alloc_len = 100;
+ char *ptr = reinterpret_cast<char*>(calloc(1, alloc_len));
+ for (size_t i = 0; i < alloc_len; i++) {
+ ASSERT_EQ(0, ptr[i]);
+ }
+ free(ptr);
+ mallopt(M_THREAD_DISABLE_MEM_INIT, 0);
+#else
+ GTEST_SKIP() << "bionic-only test";
+#endif
+}
+
TEST(malloc, calloc_illegal) {
SKIP_WITH_HWASAN;
errno = 0;