Skip to content

Trait object debug - #45897

Merged
bors merged 2 commits into
rust-lang:masterfrom
tromey:trait-object-debug
Nov 17, 2017
Merged

Trait object debug#45897
bors merged 2 commits into
rust-lang:masterfrom
tromey:trait-object-debug

Conversation

@tromey

@tromeytromey commented Nov 9, 2017

Copy link
Copy Markdown
Contributor

This enables better debugging of trait objects. See the individual commits for explanations. This required an LLVM bump.

@kennytmkennytm added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Nov 10, 2017
@bors

bors commented Nov 11, 2017

Copy link
Copy Markdown
Collaborator

☔ The latest upstream changes (presumably #45806) made this pull request unmergeable. Please resolve the merge conflicts.

@alexcrichton

alexcrichton commented Nov 12, 2017

Copy link
Copy Markdown
Member

r? @michaelwoerister

michaelwoerister
michaelwoerister approved these changes Nov 13, 2017
View reviewed changes

@michaelwoeristermichaelwoerister left a comment

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Looks good to me, thanks @tromey!

@tromey
tromeyforce-pushed the trait-object-debug branch 2 times, most recently from 8c9a797 to ab4da8cCompareNovember 13, 2017 19:11
@tromey

tromey commented Nov 14, 2017

Copy link
Copy Markdown
ContributorAuthor

So far I haven't managed to reproduce that failure.

@kennytmkennytm added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Nov 14, 2017
@tromey

tromey commented Nov 14, 2017

Copy link
Copy Markdown
ContributorAuthor

My current theory is that this is failing due to an unmodified LLVM; and so the patch will need some tweaks.

@tromey

tromey commented Nov 14, 2017

Copy link
Copy Markdown
ContributorAuthor

Looking at the patches, I still don't see how that would be possible, but I'm rebuilding without the LLVM patch to be sure.

@tromey

tromey commented Nov 14, 2017

Copy link
Copy Markdown
ContributorAuthor

I rebuilt without the LLVM bump and didn't see this failure. Now I don't have a theory about what is going wrong. Maybe I need to build specifically against whatever LLVM travis is using.

@cuviper

cuviper commented Nov 14, 2017

Copy link
Copy Markdown
Member

The first CI run uses Ubuntu's llvm-3.9. The rest should use rust's own llvm.

@tromey

tromey commented Nov 15, 2017

Copy link
Copy Markdown
ContributorAuthor

The first CI run uses Ubuntu's llvm-3.9

Thanks. I got it to fail with my system llvm.

@tromey

tromey commented Nov 15, 2017

Copy link
Copy Markdown
ContributorAuthor

The bug is that the patch is passing in NULL for the linkage name of the vtable.

@tromey
Allow minimum system LLVM version in tests
a512228
This adds a "min-system-llvm-version" directive, so that a test can
indicate that it will either work with rust-llvm or with some minimal
system LLVM. This makes it simpler to write a test that requires an
LLVM patch that landed upstream and was then backported to rust-llvm.
@tromey
Emit debug info for trait object pointer
ae4cc60
Emit better debugging information for a trait object pointer. In
particular, now:
* The fields are explicitly represented in the DWARF;
* DWARF for the vtable itself is emitted; and
* The DWARF for the vtable's type has a DW_AT_containing_type which
points to the concrete type for which the vtable was emitted. This is
a small DWARF extension, that allows debuggers to determine the real
type of the object to which a trait object points.
I'll submit the gdb patch to take advantage of this new debuginfo once
this lands.
The vtable type is not currently complete -- it doesn't include members
for the pointers it contains. This information was not needed for this
feature.
This addresses part 1 of rust-lang#1563.
@kennytmkennytm added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Nov 15, 2017
@kennytm

kennytm commented Nov 15, 2017

Copy link
Copy Markdown
Member

@tromey I think this is ready to be reviewed or merged? cc @michaelwoerister

@tromey

tromey commented Nov 15, 2017

Copy link
Copy Markdown
ContributorAuthor

@kennytm yes - it was reviewed once, then I made a small change to address the test failures. A re-review would be good.

@michaelwoerister

michaelwoerister commented Nov 16, 2017

Copy link
Copy Markdown
Member

@bors r+

@bors

bors commented Nov 16, 2017

Copy link
Copy Markdown
Collaborator

📌 Commit ae4cc60 has been approved by michaelwoerister

@kennytmkennytm added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Nov 16, 2017
@bors

bors commented Nov 16, 2017

Copy link
Copy Markdown
Collaborator

⌛ Testing commit ae4cc60 with merge d59f66d...

bors added a commit that referenced this pull request Nov 16, 2017
@bors
Auto merge of#45897- tromey:trait-object-debug, r=michaelwoerister
d59f66d
Trait object debug
This enables better debugging of trait objects. See the individual commits for explanations. This required an LLVM bump.
@bors

bors commented Nov 17, 2017

Copy link
Copy Markdown
Collaborator

☀️ Test successful - status-appveyor, status-travis
Approved by: michaelwoerister
Pushing d59f66d to master...

@bors
bors merged commit ae4cc60 into rust-lang:masterNov 17, 2017
@borsbors mentioned this pull request Nov 17, 2017
Merged
@tromey
tromey deleted the trait-object-debug branch November 17, 2017 05:34
@cuvipercuviper mentioned this pull request Jun 29, 2018
Merged
Sign up for freeto join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

1 more reviewer
@michaelwoeristermichaelwoeristermichaelwoerister approved these changes
Reviewers whose approvals may not affect merge requirements

Assignees

@michaelwoeristermichaelwoerister

Labels

S-waiting-on-borsStatus: Waiting on bors to run and complete tests. Bors will change the label on completion.

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

6 participants

@tromey@bors@alexcrichton@cuviper@kennytm@michaelwoerister