fix(txtdata): avoid UB in _ftoa bit shifts#1817
Open
robekl wants to merge 1 commit intomeshcore-dev:devfrom
Open
fix(txtdata): avoid UB in _ftoa bit shifts#1817robekl wants to merge 1 commit intomeshcore-dev:devfrom
robekl wants to merge 1 commit intomeshcore-dev:devfrom
Conversation
Use unsigned intermediate shifts when deriving integer and fractional parts to avoid signed left-shift undefined behavior under UBSAN. Keeps formatting behavior intact while making sanitizer runs pass.
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Summary
Removes undefined behavior in float-to-text conversion bit operations in
TxtDataHelpers.cpp.Bug
_ftoaused signed shift operations that can invoke undefined behavior for certain values/bit patterns.Trigger
Call float formatting on inputs that drive the problematic signed shift path in conversion internals.
Impact
Fix
Switched problematic shift intermediates to unsigned types so bit operations are well-defined across compilers and platforms.