diff --git a/build/toolchain/BUILD.gn b/build/toolchain/BUILD.gn
index c152b39..cdceaf9 100644
--- a/build/toolchain/BUILD.gn
+++ b/build/toolchain/BUILD.gn
@@ -28,14 +28,14 @@
   extra_cflags =
       "-nostdinc -isystem" +
       rebase_path("//prebuilts/linux-aarch64/musl/include") + " -isystem" +
-      rebase_path("//prebuilts/linux-x64/clang/lib64/clang/8.0.4/include") +
+      rebase_path("//prebuilts/linux-x64/clang/lib64/clang/9.0.3/include") +
       " -isystem" + rebase_path("//inc/system")
   extra_defines = "-D_LIBCPP_HAS_MUSL_LIBC=1 -D_GNU_SOURCE=1"
   extra_ldflags = "-no-pie -lc --library-path=" +
                   rebase_path("//prebuilts/linux-aarch64/musl/lib/") + " " +
                   rebase_path("//prebuilts/linux-aarch64/musl/lib/crt1.o") +
                   " " + rebase_path(
-                      "//prebuilts/linux-x64/clang/lib64/clang/8.0.4/lib/linux/libclang_rt.builtins-aarch64-android.a")
+                      "//prebuilts/linux-x64/clang/lib64/clang/9.0.3/lib/linux/libclang_rt.builtins-aarch64-android.a")
   toolchain_args = {
     use_platform = true
     plat_arch = "fake"
diff --git a/build/toolchain/embedded.gni b/build/toolchain/embedded.gni
index beed6aa..476873c 100644
--- a/build/toolchain/embedded.gni
+++ b/build/toolchain/embedded.gni
@@ -120,7 +120,7 @@
     # from the Android prebuilt Clang.
     extra_cflags +=
         " -target ${invoker.target} -fcolor-diagnostics -nostdinc -isystem" +
-        rebase_path("//prebuilts/linux-x64/clang/lib64/clang/8.0.4/include") +
+        rebase_path("//prebuilts/linux-x64/clang/lib64/clang/9.0.3/include") +
         " -isystem" + rebase_path("//inc/system")
     extra_ldflags +=
         " -O2 -lto-O2 --icf=all --fatal-warnings --color-diagnostics"
diff --git a/prebuilts b/prebuilts
index 52c2969..16937d0 160000
--- a/prebuilts
+++ b/prebuilts
@@ -1 +1 @@
-Subproject commit 52c2969f621c443130e93da7ae16eea8d8fe620b
+Subproject commit 16937d08ad8cc9225fd54b0caa282c84bc523947
diff --git a/test/vmapi/primary_with_secondaries/memory_sharing.c b/test/vmapi/primary_with_secondaries/memory_sharing.c
index 61505d0..76d0739 100644
--- a/test/vmapi/primary_with_secondaries/memory_sharing.c
+++ b/test/vmapi/primary_with_secondaries/memory_sharing.c
@@ -138,10 +138,10 @@
 		SPCI_MEMORY_OUTER_SHAREABLE, SPCI_MEMORY_INNER_SHAREABLE};
 	uint32_t vms[] = {HF_PRIMARY_VM_ID, SERVICE_VM0, SERVICE_VM1};
 
-	int i = 0;
-	int j = 0;
-	int k = 0;
-	int l = 0;
+	size_t i = 0;
+	size_t j = 0;
+	size_t k = 0;
+	size_t l = 0;
 
 	for (i = 0; i < ARRAY_SIZE(vms); ++i) {
 		for (j = 0; j < ARRAY_SIZE(lend_access); ++j) {