Hello, Building 64-bit Ruby 2.5.9 on AIX using xlc compiler. Miniruby hangs during "generating encdb.h". Call-stacks of the miniruby process: ---------- tid# 24838655 (pthread ID: 1) ---------- 0x00000001001267f0 ruby_atomic_compare_and_swap(0x1100636b8, 0x1b15a7001b15a7, 0x1af5a7001af5a7) + 0x30 0x000000010001c058 atomic_sub_nounderflow(0x1100636b8, 0x2000) + 0x58 0x0000000100025880 objspace_malloc_increase(0x1100636b0, 0x1102f8f30, 0x0, 0x2000, 0x200000002) + 0x80 0x000000010001eb8c objspace_xfree(0x1100636b0, 0x1102f8f30, 0x2000) + 0x4c 0x000000010001ec10 ruby_sized_xfree(0x1102f8f30, 0x2000) + 0x30 0x00000001001e71a4 free_io_buffer(0x1102f8e90) + 0x24 0x00000001001e7394 fptr_finalize(0x1102f8e50, 0x0) + 0x34 0x00000001001e7438 rb_io_fptr_cleanup(0x1102f8e50, 0x0) + 0x58 0x00000001001e7560 io_close_fptr(0x1101ad7c0) + 0xe0 0x00000001001e7674 rb_io_close(0x1101ad7c0) + 0x14 0x0000000100007378 restore_load_file(0xfffffffffffe900) + 0x38 0x00000001000083dc rb_ensure(0x110023278, 0xfffffffffffe900, 0x110023290, 0xfffffffffffe900) + 0x1bc 0x00000001000009a0 load_file(0x1101ae468, 0x1101ae698, 0x1101ad7c0, 0x100000001, 0xfffffffffffefb0) + 0x60 0x0000000100005688 process_options(0x60000000b, 0xffffffffffff4c8, 0xfffffffffffefb0) + 0xa48 0x0000000100005c50 ruby_process_options(0xb0000000b, 0xffffffffffff4a0) + 0xd0 0x000000010000be70 ruby_options(0xb0000000b, 0xffffffffffff4a0) + 0xd0 0x0000000100000560 main(0xb0000000b, 0xffffffffffff4a0) + 0x60 0x0000000100000268 __start() + 0x70 ---------- tid# 21168597 (pthread ID: 258) ---------- 0x0900000000168334 __fd_poll(??, ??, ??) + 0xb4 0x000000010011d6c4 poll(0x1102dc6d8, 0x2, 0xffffffffffffffff) + 0x24 0x000000010011d790 timer_thread_sleep(0x110062678) + 0x90 0x000000010011d944 thread_timer(0x110062678) + 0x44 0x09000000005abfe8 _pthread_body(??) + 0xe8 Any suggestions on how to fix this? Thanks.