RFR: JDK-8193055 ADD_JVM_ARG_IF_OK always fails

[David Holmes]

Hi Magnus,

On 5/12/2017 8:49 PM, Magnus Ihse Bursie wrote:
> We mistakenly use -XX:-UnlockDiagnosticVMOptions instead of 
> -XX:+UnlockDiagnosticVMOptions in a ADD_JVM_ARG_IF_OK call. This means 
> that the test will always fail and the arguments will never be added to 
> the command line.
> 
> Since this has been the case all time along, it's probably not that 
> important, but it was added to keep down the logging when using a debug 
> build as boot jdk, which has probably not been tested that much either.

LogVMOutput will only be turned on in a debug build if you also enable 
specific (mostly debug only) log/print/trace options.

> We should either fix this or remove the arguments completely.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8193055
> Patch inline:
> diff --git a/make/autoconf/boot-jdk.m4 b/make/autoconf/boot-jdk.m4
> --- a/make/autoconf/boot-jdk.m4
> +++ b/make/autoconf/boot-jdk.m4
> @@ -354,7 +354,7 @@
>     AC_MSG_CHECKING([flags for boot jdk java command] )
> 
>     # Disable special log output when a debug build is used as Boot JDK...
> -  ADD_JVM_ARG_IF_OK([-XX:-PrintVMOptions -XX:-UnlockDiagnosticVMOptions 
> -XX:-LogVMOutput],boot_jdk_jvmargs,[$JAVA])
> +  ADD_JVM_ARG_IF_OK([-XX:-PrintVMOptions -XX:+UnlockDiagnosticVMOptions 
> -XX:-LogVMOutput],boot_jdk_jvmargs,[$JAVA])

Fix is fine. But you could probably remove them too. Do you recall why 
this was added? It may relate to something now migrated to Unified Logging.

David
-----

>     # Force en-US environment
>     ADD_JVM_ARG_IF_OK([-Duser.language=en 
> -Duser.country=US],boot_jdk_jvmargs,[$JAVA])
> 
> /Magnus