build

Reinstate %makearray_dynamic #14626

Job	Run time
flambda2_runtime5	15m 11s
flambda2_dev	11m 18s
flambda2_dev_runtime5	14m 29s
flambda2_debug_runtime5	21m 46s
flambda2_debug_runtime	13m 15s
flambda2_o3	12m 2s
flambda2_o3_heap	11m 10s
flambda2_o3_advanced_meet_frame_pointers_runtime5_polling	16m 32s
flambda2_o3_advanced_meet_frame_pointers_runtime5_debug	20m 47s
flambda2_frame_pointers_oclassic_polling	11m 18s
flambda2_macos_arm64	9m 29s
flambda2_macos_arm64_irc	11m 51s
flambda2_macos_arm64_ls	10m 4s
flambda2_macos_arm64_gi	9m 50s
irc	11m 53s
irc_polling	11m 54s
irc_frame_pointers	11m 57s
ls	12m 3s
gi	12m 9s
cfg-selection	11m 47s
vectorizer	11m 47s
	4h 32m 32s

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