--- a/make/autoconf/flags-cflags.m4	Thu Jun 14 15:46:19 2018 +0200
+++ b/make/autoconf/flags-cflags.m4	Thu Sep 20 21:47:13 2018 +0200
@@ -196,7 +196,7 @@
       WARNINGS_ENABLE_ALL_CXXFLAGS="$WARNINGS_ENABLE_ADDITIONAL_CXX"
 
       DISABLED_WARNINGS_JUST_GET_THIS_PASS="unused-variable unused-function unused-but-set-variable undef unused-value unused-label pointer-arith"
-      DISABLED_WARNINGS="unknown-warning unused-parameter $DISABLED_WARNINGS_JUST_GET_THIS_PASS"
+      DISABLED_WARNINGS="unused-parameter $DISABLED_WARNINGS_JUST_GET_THIS_PASS"
 
       # Repeate the check for the BUILD_CC and BUILD_CXX. Need to also reset
       # CFLAGS since any target specific flags will likely not work with the

--- a/make/hotspot/lib/CompileJvm.gmk	Thu Jun 14 15:46:19 2018 +0200
+++ b/make/hotspot/lib/CompileJvm.gmk	Thu Sep 20 21:47:13 2018 +0200
@@ -106,6 +106,10 @@
   JVM_EXCLUDE_PATTERNS += x86_32
 endif
 
+ifneq ($(DEBUG_LEVEL), release)
+  DISABLED_WARNINGS_gcc += extra
+endif
+
 # Inline assembly for solaris
 ifeq ($(OPENJDK_TARGET_OS), solaris)
   ifeq ($(OPENJDK_TARGET_CPU), x86_64)
@@ -164,7 +168,8 @@
         missing-field-initializers unused-but-set-variable char-subscripts \
         array-bounds narrowing empty-body unused-but-set-parameter \
         maybe-uninitialized logical-op \
-        implicit-fallthrough expansion-to-defined, \
+        implicit-fallthrough expansion-to-defined strict-overflow sequence-point \
+        $(DISABLED_WARNINGS_gcc), \
     DISABLED_WARNINGS_clang := tautological-compare, \
     DISABLED_WARNINGS_solstudio := $(DISABLED_WARNINGS_solstudio) \
         labelnotused hidef w_novirtualdescr inlafteruse \