Skip to content

GetCommonAncestorLevel: work around bit_width return type bug #431

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom
Merged
jmr merged 3 commits into from
May 20, 2025
Merged

GetCommonAncestorLevel: work around bit_width return type bug #431

jmr merged 3 commits into from
May 20, 2025

Conversation

@idevtm
Copy link

@idevtm idevtm commented May 19, 2025 •
edited
Loading

This is meant to work around the situation when absl::bit_width is unsigned long.

error: no matching function for call to 'max'
[build]   return max(61 - absl::bit_width(bits), -1) >> 1;
[build]          ^~~
[build] /usr/bin/../lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/algorithmfwd.h:407:5: note: candidate template ignored: deduced conflicting types for parameter '_Tp' ('unsigned long' vs. 'int')

ref abseil/abseil-cpp#1890
ref #421 (comment)

System: Debian 12
Compiler: Clang-15

@idevtm idevtm marked this pull request as ready for review May 19, 2025 15:57
@jmr jmr changed the title Fix type conversion in GetCommonAncestorLevel for bit width calculation GetCommonAncestorLevel: work around bit_width return type bug May 19, 2025
jmr added 2 commits May 19, 2025 21:09
@jmr
s2cell_id.cc: Add comment and move cast
b32a122 
Add comment to document workaround.

Move cast.  It's the `bit_width` return value that is wrong, so cast that.
@jmr
Fix line length
ef01b21
@jmr jmr merged commit 473a989 into google:master May 20, 2025
10 checks passed
@BrewTestBot BrewTestBot mentioned this pull request Dec 1, 2025
Merged
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Assignees

No one assigned

Labels

None yet

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

3 participants

@idevtm @jmr @stefankarschti