Avoid infinite recursion in GetBitSize/GetBitAlign #3089
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
If the lldb::Type does not have static size info attached to it, Type::GetByteSize() calls back into TypeSystemSwiftTypeRef(), creating an infinite recursion. This patch avoids this by adding an accessor that only returns the static or precomputed byte size without the recursion. rdar://79874370
|
@swift-ci test |
This was referenced Jul 13, 2021
kastiglione
approved these changes
Jul 13, 2021
| struct SwiftType : public Type { | ||
| /// Avoid a potential infinite recursion because | ||
| /// Type::GetByteSize() may call into this function again. | ||
| llvm::Optional<uint64_t> GetStaticByteSize() { |
There was a problem hiding this comment.
Thoughts on adding this function directly to Type?
There was a problem hiding this comment.
I did it in this odd way is to minimize the diff between swift-lldb and llvm.org lldb.
| @@ -3179,9 +3193,10 @@ TypeSystemSwiftTypeRef::GetTypeBitAlign(opaque_compiler_type_t type, | |||
| // alignment information out of DWARF. Because it is stored in the | |||
| // Type object we need to look that up by name again. | |||
| if (TypeSP type_sp = LookupTypeInModule(type)) | |||
| return type_sp->GetLayoutCompilerType().GetTypeBitAlign(exe_scope); | |||
| if (type_sp->GetLayoutCompilerType().GetOpaqueQualType() != type) | |||
There was a problem hiding this comment.
Suggestion: a comment saying when/why this inequality happens.
There was a problem hiding this comment.
It's again to avoid an infinite recursion. I'll add a comment.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
rdar://79874370