build

Reinstate %makearray_dynamic #14623

Job	Run time
flambda2_runtime5	15m 9s
flambda2_dev	10m 29s
flambda2_dev_runtime5	14m 16s
flambda2_debug_runtime5	21m 44s
flambda2_debug_runtime	13m 5s
flambda2_o3	12m 7s
flambda2_o3_heap	11m 22s
flambda2_o3_advanced_meet_frame_pointers_runtime5_polling	16m 32s
flambda2_o3_advanced_meet_frame_pointers_runtime5_debug	21m 19s
flambda2_frame_pointers_oclassic_polling	11m 26s
flambda2_macos_arm64	9m 56s
flambda2_macos_arm64_irc	9m 19s
flambda2_macos_arm64_ls	10m 1s
flambda2_macos_arm64_gi	9m 36s
irc	11m 51s
irc_polling	12m 58s
irc_frame_pointers	11m 57s
ls	11m 50s
gi	12m 23s
cfg-selection	11m 43s
vectorizer	12m 18s
	4h 31m 21s

Provide feedback