[9] RFR of 8140630: java/nio/Buffer/Basic.java crashes vm on linux-x64 using latest devkit to build

[Brian Burkhalter]

Please review at your convenience.

Issue:	https://bugs.openjdk.java.net/browse/JDK-8140630
Patch:	Included below

The change is to compile src/java.base/share/native/libjava/Bits.c only into libjava.so with normal optimization level (-O2) instead of high optimization level (-O3). The other objects in libjava are not affected. This is for 64-bit Linux only. With this patch applied, java/nio/Buffer/Basic.java now passes on all platforms and there is no crash.

Thanks,

Brian

--- a/make/lib/CoreLibraries.gmk
+++ b/make/lib/CoreLibraries.gmk
@@ -139,6 +139,12 @@
   endif
 endif
 
+ifeq ($(OPENJDK_TARGET_OS), linux)
+  ifeq ($(OPENJDK_TARGET_CPU), x86_64)
+    BUILD_LIBJAVA_Bits.c_CFLAGS := $(C_O_FLAG_NORM)
+  endif
+endif
+
 $(eval $(call SetupNativeCompilation,BUILD_LIBJAVA, \
     LIBRARY := java, \
     OUTPUT_DIR := $(INSTALL_LIBRARIES_HERE), \