This is because of a BC-breaking core Drupal change which apparently was never deprecated and doesn't trigger errors with the coder tools. Drupal core requires Doctrine, but if contrib actually tries to use Doctrine in PHP 7.4 it breaks. Core worked around this by forking it's own copy of some Doctrine code.

See #2631202: Doctrine no longer supports SimpleAnnotationReader, incorporate a solution into core

Support from Acquia helps fund testing for Drupal Acquia logo

Comments

TR created an issue. See original summary.

  • TR committed 6e4850d on 8.x-3.x
    Issue #3160115 by TR: Drupal 8 tests fail with PHP 7.4
    
TR’s picture

Title: Tests fail with PHP 7.4 » Drupal 8 tests fail with PHP 7.4
Priority: Normal » Major
Status: Needs review » Fixed

Committed.

jonathan1055’s picture

Thanks for the background info.

Status: Fixed » Closed (fixed)

Automatically closed - issue fixed for 2 weeks with no activity.