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

[Tim Bell]

Hi Brian:

> 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.

Looks good to me.

Tim

> 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), \