Flang Biweekly Sync - Notes from the May 13, 2020 call

Flang team,

Here are the notes from the May 13th, 2020 Flang biweekly call.

The next Flang Technical Community will be Monday, May 18th, 8:30 AM Pacific Time.

The next Flang biweekly call will be Wednesday, May 27th, 2020 at 8:30 AM Pacific Time.

Information for joining these calls and the Slack channel is at the end of this email.

Let me know if you have any topics you would like covered in the next call.

Thank you.

Gary Klimowicz


  • Follow-on meeting to discuss LLVM alias analysis
  • LLVM Flang development update
  • Original Flang development update


  • Alias analysis discussion

  • In a previous technical call we discussed alias analysis for Fortran. Hal is scheduling a follow-on meeting to discuss potential improvements to LLVM’s alias analysis to support handling restrict and restrict-like semantics. The Doodle poll to find a time to hold this call can be found at https://doodle.com/poll/evhwr2eyfvcf8ib3.

  • LLVM Flang update

  • Arm stood up a flang buildbot for Arm AArch64 at lab.llvm.org - see http://lab.llvm.org:8011/builders/flang-aarch64-ubuntu.

  • Arm submitted work on OpenMP for parallel operation (lowering of simple subroutine without arguments).

  • Handle size and offset computations and added constraint enforcement for COMMON and EQUIVALENCE.

  • New implementation for TYPE constraints C741-C750.

  • Continued work on lowering to FIR for alternate returns and end-of-I/O statement branching.

  • Continued work on lowering: DNINT/FLOOR and STOP/ERROR STOP based on runtime updates.

  • Continued work on lowering DATA statements and array initializers, including multidimensional arrays.

  • AMD submitted semantics for SELECT RANK.

  • See the detailed notes below for other Flang development updates.

  • Original Flang Dev news and updates

  • We’ve pushed a simple change to the stage branch of flang and are waiting for validation before merging into Flang.

  • Flang Community Technical Biweekly Call

  • The last call was Monday, May 4th: We discussed the status of the fir-dev branch and the plan to continue to migrate it to the master.

  • The next technical call is scheduled for May 18th. We hope to discuss where people can contribute to Flang.

  • Now what? Hal Finkel encourages people to add both small and large technical topics to the Google Doc for the technical call. The link to the Google Doc can be found in the notes below.

**Details (**Updates below are in bold)