Merge "Revert "Enable the scudo native allocator."" am: c8226ec23d am: 0bce21480c

Change-Id: I10023e34bbcebb0ce0c54e672e567c118a1b46d6
diff --git a/libc/Android.bp b/libc/Android.bp
index daca9c4..c764cb9 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -94,7 +94,7 @@
 cc_defaults {
     name: "libc_native_allocator_defaults",
 
-    defaults: ["libc_scudo_defaults"],
+    defaults: ["libc_jemalloc5_defaults"],
 }
 
 cc_defaults {
@@ -2629,6 +2629,7 @@
 
 cc_library_shared {
     name: "libc_scudo",
+    defaults: ["libc_scudo_wrapper_defaults"],
     vendor_available: true,
     stl: "none",
     system_shared_libs: [],
diff --git a/libc/bionic/malloc_common_dynamic.cpp b/libc/bionic/malloc_common_dynamic.cpp
index 020cd23..2cb1e8a 100644
--- a/libc/bionic/malloc_common_dynamic.cpp
+++ b/libc/bionic/malloc_common_dynamic.cpp
@@ -294,10 +294,17 @@
   return true;
 }
 
+// Note about USE_SCUDO. This file is compiled into libc.so and libc_scudo.so.
+// When compiled into libc_scudo.so, the libc_malloc_* libraries don't need
+// to be loaded from the runtime namespace since libc_scudo.so is not from
+// the runtime APEX, but is copied to any APEX that needs it.
+#ifndef USE_SCUDO
 extern "C" struct android_namespace_t* android_get_exported_namespace(const char* name);
+#endif
 
 void* LoadSharedLibrary(const char* shared_lib, const char* prefix, MallocDispatch* dispatch_table) {
   void* impl_handle = nullptr;
+#ifndef USE_SCUDO
   // Try to load the libc_malloc_* libs from the "runtime" namespace and then
   // fall back to dlopen() to load them from the default namespace.
   //
@@ -316,6 +323,7 @@
     };
     impl_handle = android_dlopen_ext(shared_lib, RTLD_NOW | RTLD_LOCAL, &dlextinfo);
   }
+#endif
 
   if (impl_handle == nullptr) {
     impl_handle = dlopen(shared_lib, RTLD_NOW | RTLD_LOCAL);