[8u] 8247570: Build failure with -JFR after JDK-8233197 backport

[Severin Gehwolf]

Hi Aleksey,

On Mon, 2020-06-15 at 10:04 +0200, Aleksey Shipilev wrote:
> 8u-specific bug, recently introduced:
>   https://bugs.openjdk.java.net/browse/JDK-8247570

jdk8u/jdk8u-dev specific, actually :-)

> Look at this block to spot the issue:
>   https://hg.openjdk.java.net/jdk8u/jdk8u-dev/hotspot/rev/26d1803768c7#l11.22
> 
> I believe the trailing "}" is excessive, so I removed it and unindented the block back:
> 
> diff -r 26d1803768c7 src/share/vm/runtime/thread.cpp
> --- a/src/share/vm/runtime/thread.cpp   Thu Jun 11 12:17:25 2020 +0200
> +++ b/src/share/vm/runtime/thread.cpp   Mon Jun 15 09:56:30 2020 +0200
> @@ -3490,19 +3490,18 @@
>      MetaspaceShared::preload_and_dump(CHECK_0);
>      ShouldNotReachHere();
>    }
> 
>  #if !INCLUDE_JFR
> -    // if JFR is not enabled at the build time keep the original JvmtiExport location
> -
> -    // Always call even when there are not JVMTI environments yet, since environments
> -    // may be attached late and JVMTI must track phases of VM execution
> -    JvmtiExport::enter_start_phase();
> -
> -    // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
> -    JvmtiExport::post_vm_start();
> -  }
> +  // if JFR is not enabled at the build time keep the original JvmtiExport location
> +
> +  // Always call even when there are not JVMTI environments yet, since environments
> +  // may be attached late and JVMTI must track phases of VM execution
> +  JvmtiExport::enter_start_phase();
> +
> +  // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
> +  JvmtiExport::post_vm_start();
>  #endif
> 
>    {
>      TraceTime timer("Initialize java.lang classes", TraceStartupTime);
> 
> 
> Testing: x86_64 {server,zero} builds

Seems to be the same fix than Andrew Hughes did for jdk8u/jdk8u[1]. 

Looks good. Please coordinate with him to get this pushed.

Thanks,
Severin

[1] https://bugs.openjdk.java.net/browse/JDK-8247448
    http://mail.openjdk.java.net/pipermail/jdk8u-dev/2020-June/011954.html