[all-commits] [llvm/llvm-project] 7f5928: [flang] Avoid cascading error in subscript triplet

[Tim Keith via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 7f5928ef5a5743ee7e65c6c9d1e1c9bc6af03063
      https://github.com/llvm/llvm-project/commit/7f5928ef5a5743ee7e65c6c9d1e1c9bc6af03063
  Author: Tim Keith <tkeith at nvidia.com>
  Date:   2020-08-10 (Mon, 10 Aug 2020)

  Changed paths:
    M flang/lib/Semantics/expression.cpp
    M flang/test/Semantics/assign04.f90

  Log Message:
  -----------
  [flang] Avoid cascading error in subscript triplet

If a bound of a subscript triplet is present but fails to analyze
due to an error, return nullopt rather than returning a Triplet with
that bound missing. This is so we can distinguish an absent bound from
an erroneous one and avoid spurious errors.

Differential Revision: https://reviews.llvm.org/D85672