--- a/make/linux/makefiles/zeroshark.make	Mon May 07 18:14:16 2018 +0100
+++ b/make/linux/makefiles/zeroshark.make	Mon May 07 18:29:21 2018 +0100
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
 # Copyright 2007, 2008 Red Hat, Inc.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
@@ -29,11 +29,6 @@
 ifeq ($(USE_CLANG), true)
   WARNING_FLAGS += -Wno-undef
 endif
-# Suppress some warning flags that are normally turned on for hotspot,
-# because some of the zero code has not been updated accordingly.
-WARNING_FLAGS += -Wno-return-type \
-  -Wno-format-nonliteral -Wno-format-security \
-  -Wno-maybe-uninitialized
 
 # The copied fdlibm routines in sharedRuntimeTrig.o must not be optimized
 OPT_CFLAGS/sharedRuntimeTrig.o = $(OPT_CFLAGS/NOOPT)

--- a/src/cpu/zero/vm/cppInterpreter_zero.cpp	Mon May 07 18:14:16 2018 +0100
+++ b/src/cpu/zero/vm/cppInterpreter_zero.cpp	Mon May 07 18:29:21 2018 +0100
@@ -100,7 +100,7 @@
     case T_DOUBLE:
     case T_VOID:
       return result;
-    default  : ShouldNotReachHere();
+    default  : ShouldNotReachHere(); return NULL_WORD;
   }
 }
 

--- a/src/cpu/zero/vm/interpreterRT_zero.cpp	Mon May 07 18:14:16 2018 +0100
+++ b/src/cpu/zero/vm/interpreterRT_zero.cpp	Mon May 07 18:29:21 2018 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2007, 2008, 2010 Red Hat, Inc.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -62,7 +62,7 @@
 }
 
 void InterpreterRuntime::SignatureHandlerGeneratorBase::push(BasicType type) {
-  ffi_type *ftype;
+  ffi_type *ftype = NULL;
   switch (type) {
   case T_VOID:
     ftype = &ffi_type_void;

--- a/src/os_cpu/linux_zero/vm/os_linux_zero.cpp	Mon May 07 18:14:16 2018 +0100
+++ b/src/os_cpu/linux_zero/vm/os_linux_zero.cpp	Mon May 07 18:29:21 2018 +0100
@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
- * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc.
+ * Copyright 2016 Red Hat, Inc.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -61,6 +61,7 @@
 
 frame os::get_sender_for_C_frame(frame* fr) {
   ShouldNotCallThis();
+  return frame(NULL, NULL); // silence compile warning.
 }
 
 frame os::current_frame() {
@@ -98,16 +99,19 @@
 
 address os::Linux::ucontext_get_pc(ucontext_t* uc) {
   ShouldNotCallThis();
+  return NULL; // silence compile warnings
 }
 
 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
                                         intptr_t** ret_sp,
                                         intptr_t** ret_fp) {
   ShouldNotCallThis();
+  return NULL; // silence compile warnings
 }
 
 frame os::fetch_frame_from_context(void* ucVoid) {
   ShouldNotCallThis();
+  return frame(NULL, NULL); // silence compile warnings
 }
 
 extern "C" JNIEXPORT int
@@ -247,11 +251,16 @@
   }
 #endif // !PRODUCT
 
-  const char *fmt = "caught unhandled signal %d";
   char buf[64];
 
-  sprintf(buf, fmt, sig);
+  sprintf(buf, "caught unhandled signal %d", sig);
+
+// Silence -Wformat-security warning for fatal()
+PRAGMA_DIAG_PUSH
+PRAGMA_FORMAT_NONLITERAL_IGNORED
   fatal(buf);
+PRAGMA_DIAG_POP
+  return true; // silence compiler warnings
 }
 
 void os::Linux::init_thread_fpu_state(void) {
@@ -260,6 +269,7 @@
 
 int os::Linux::get_fpu_control_word() {
   ShouldNotCallThis();
+  return -1; // silence compile warnings
 }
 
 void os::Linux::set_fpu_control_word(int fpu) {
@@ -408,6 +418,7 @@
 
 extern "C" {
   int SpinPause() {
+      return -1; // silence compile warnings
   }
 
 

--- a/src/os_cpu/linux_zero/vm/thread_linux_zero.hpp	Mon May 07 18:14:16 2018 +0100
+++ b/src/os_cpu/linux_zero/vm/thread_linux_zero.hpp	Mon May 07 18:29:21 2018 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -110,6 +110,7 @@
                                            void* ucontext,
                                            bool isInJava) {
     ShouldNotCallThis();
+    return false; // silence compile warning
   }
 
   // These routines are only used on cpu architectures that