diff -r c2d95df2c54e -r 7cbd1b2c139b hotspot/make/linux/makefiles/gcc.make
--- a/hotspot/make/linux/makefiles/gcc.make	Mon Oct 19 15:03:58 2015 +0200
+++ b/hotspot/make/linux/makefiles/gcc.make	Thu Oct 22 13:07:10 2015 -0400
@@ -223,6 +223,8 @@
     WARNING_FLAGS += -Wtype-limits
     # GCC < 4.8 don't accept this flag for C++.
     WARNING_FLAGS += -Wno-format-zero-length
+    # GCC 4.8 reports less false positives than the older compilers.
+    WARNING_FLAGS += -Wuninitialized
   endif
 endif