As of https://github.com/mongodb/mongo/commit/24aa56a6ed096a470f1380709b87084ff74106b5, build action debug timings no longer appear in the log output for compile tasks. Compare:

• Before: https://evergreen.mongodb.com/task_log_raw/mongodb_mongo_master_enterprise_rhel_80_64_bit_dynamic_required_compile_dist_test_c2f5a747a5c55f35f51ce59d58f707c75940ba23_21_04_01_17_30_57/0?type=T#L504
• After: https://evergreen.mongodb.com/task_log_raw/mongodb_mongo_master_enterprise_rhel_80_64_bit_dynamic_required_compile_dist_test_24aa56a6ed096a470f1380709b87084ff74106b5_21_04_01_17_32_12/0?type=T#L367

The migration of the scons compile function into the external script evergreen/scons_compile.sh seems to be the cause. While fixing that issue, it is important to ensure that build flags other than --debug=time have also not unintentionally been omitted or changed.