VM: Remove too strict assertion in rethrow.

VM: Remove too strict assertion in rethrow.

With custom zones and async code we may end up invoking rethrow
with an error object where the stacktrace is not initialized.

In that case we can just use the stacktrace passed into rethrow
explicitly.

Fixes #27839.

R=kustermann@google.com

Committed: https://github.com/dart-lang/sdk/commit/2e4101fc6c4544b9b0a66dc2156664bf68bf8f4a

[Florian Schneider, 2016-11-17 00:42:15]

fschneider@google.com changed reviewers:
+ kustermann@google.com

[kustermann, 2016-11-17 11:07:48]

LGTM, thanks!

https://codereview.chromium.org/2511573003/diff/1/runtime/vm/exceptions.cc
File runtime/vm/exceptions.cc (right):

https://codereview.chromium.org/2511573003/diff/1/runtime/vm/exceptions.cc#ne...
runtime/vm/exceptions.cc:412: &handler_needs_stacktrace);
Can this FindExceptionHandler() be hoisted out of the if/else branches?

https://codereview.chromium.org/2511573003/diff/1/runtime/vm/exceptions.cc#ne...
runtime/vm/exceptions.cc:418: stacktrace = existing_stacktrace.raw();
This branch doesn't need [stacktrace_field] anymore. Maybe only do the
Field::Handle(zone, LookupStacktraceField(exception) in the else-case?

[Florian Schneider, 2016-11-17 18:59:07]

https://codereview.chromium.org/2511573003/diff/1/runtime/vm/exceptions.cc
File runtime/vm/exceptions.cc (right):

https://codereview.chromium.org/2511573003/diff/1/runtime/vm/exceptions.cc#ne...
runtime/vm/exceptions.cc:412: &handler_needs_stacktrace);
On 2016/11/17 11:07:48, kustermann wrote:
> Can this FindExceptionHandler() be hoisted out of the if/else branches?

Done.

https://codereview.chromium.org/2511573003/diff/1/runtime/vm/exceptions.cc#ne...
runtime/vm/exceptions.cc:418: stacktrace = existing_stacktrace.raw();
On 2016/11/17 11:07:48, kustermann wrote:
> This branch doesn't need [stacktrace_field] anymore. Maybe only do the
> Field::Handle(zone, LookupStacktraceField(exception) in the else-case?

Done.

[Florian Schneider, 2016-11-17 20:11:37]

Description was changed from

==========
VM: Remove too strict assertion in rethrow.

With custom zones and async code we may end up invoking rethrow
with an error object where the stacktrace is not initialized.

In that case we can just use the stacktrace passed into rethrow
explicitly.

Fixes #27839.
==========

to

==========
VM: Remove too strict assertion in rethrow.

With custom zones and async code we may end up invoking rethrow
with an error object where the stacktrace is not initialized.

In that case we can just use the stacktrace passed into rethrow
explicitly.

Fixes #27839.

R=kustermann@google.com

Committed:
https://github.com/dart-lang/sdk/commit/2e4101fc6c4544b9b0a66dc2156664bf68bf8f4a
==========

[Florian Schneider, 2016-11-17 20:11:40]

Committed patchset #2 (id:20001) manually as
2e4101fc6c4544b9b0a66dc2156664bf68bf8f4a (presubmit successful).