Subject: fix GCC 12 fails to compile AArch64 due to -Wstringop-overflow

---
 hotspot/make/linux/makefiles/gcc.make | 2 +-
 hotspot/src/share/vm/opto/type.cpp    | 7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/hotspot/make/linux/makefiles/gcc.make b/hotspot/make/linux/makefiles/gcc.make
index 7dde7f096..d122f0eae 100644
--- a/hotspot/make/linux/makefiles/gcc.make
+++ b/hotspot/make/linux/makefiles/gcc.make
@@ -212,7 +212,7 @@ ifeq ($(USE_CLANG), true)
   WARNINGS_ARE_ERRORS += -Wno-return-type -Wno-empty-body
 endif
 
-WARNING_FLAGS = -Wpointer-arith -Wsign-compare -Wundef -Wunused-function -Wunused-value -Wformat=2 -Wreturn-type
+WARNING_FLAGS = -Wpointer-arith -Wsign-compare -Wundef -Wunused-function -Wunused-value -Wformat=2 -Wreturn-type -Wno-stringop-overflow
 
 ifeq ($(USE_CLANG),)
   # Since GCC 4.3, -Wconversion has changed its meanings to warn these implicit
diff --git a/hotspot/src/share/vm/opto/type.cpp b/hotspot/src/share/vm/opto/type.cpp
index 58572f137..92d4e6b70 100644
--- a/hotspot/src/share/vm/opto/type.cpp
+++ b/hotspot/src/share/vm/opto/type.cpp
@@ -2553,8 +2553,11 @@ TypeOopPtr::TypeOopPtr(TYPES t, PTR ptr, ciKlass* k, bool xk, ciObject* o, int o
                    _offset >= InstanceMirrorKlass::offset_of_static_fields()) {
           // Static fields
           assert(o != NULL, "must be constant");
-          ciInstanceKlass* k = o->as_instance()->java_lang_Class_klass()->as_instance_klass();
-          ciField* field = k->get_field_by_offset(_offset, true);
+          ciField* field = NULL;
+          if (o != NULL) {
+            ciInstanceKlass* k = o->as_instance()->java_lang_Class_klass()->as_instance_klass();
+            field = k->get_field_by_offset(_offset, true);
+          }
           assert(field != NULL, "missing field");
           BasicType basic_elem_type = field->layout_type();
           _is_ptr_to_narrowoop = UseCompressedOops && (basic_elem_type == T_OBJECT ||
-- 
2.22.0