I’ve made progress after fixing a compiler bug that prevented valid data from being written to the output register.
dEQP-GLES3.functional.transform_feedback.*
Test run totals:
Passed: 1114/1320 (84.4%)
Failed: 98/1320 (7.4%)
Not supported: 108/1320 (8.2%)
Warnings: 0/1320 (0.0%)
Waived: 0/1320 (0.0%)