Hi Everyone, I thought I'd have another go at moving to 64 bits after Esteban commented that he's regularly using it now. However the following sequence reliably crashses the 64 bit VM (Ubuntu 16.04): 1. Execute: Iceberg enableMetacelloIntegration: true. Metacello new repository: 'github://akgrant43/FileAttributes/src'; baseline: 'FileAttributes'; load. 2. Open Iceberg 3. Select the FileAttributes repository 4. Show History... 5. Select master 6. Click on the top commit $ ../vm64/pharo-ui Pharo7.0-64bit-f65af60.image pharo: malloc.c:2394: sysmalloc: Assertion `(old_top == initial_top (av) && old_size == 0) || ((unsigned long) (old_size) >= MINSIZE && prev_inuse (old_top) && ((unsigned long) old_end & (pagesize - 1)) == 0)' failed. ../vm64/pharo-ui: line 11: 13199 Aborted (core dumped) "$DIR"/"pharo-vm/pharo" "$@" I also get crashes from other operations, e.g. iceRepository pull. The result is that for me 64 bits isn't usable yet. If this isn't already known I'll open a fogbugz issue. Build info: Pharo 7.0 Build information: alpha.build.109.sha.f65af6011ac4ff31af37c8d8567bf8a5fdad8dca but has happened with other builds as well. $ ../vm64/pharo --version 5.0-201708271955 Sun Aug 27 20:00:58 UTC 2017 gcc 4.6.3 [Production Spur 64-bit VM] CoInterpreter VMMaker.oscog-eem.2265 uuid: 76b62109-629a-4c39-9641-67b53321df9a Aug 27 2017 StackToRegisterMappingCogit VMMaker.oscog-eem.2262 uuid: 8b531242-de02-48aa-b418-8d2dde0bec6c Aug 27 2017 VM: 201708271955 https://github.com/OpenSmalltalk/opensmalltalk-vm.git $ Date: Sun Aug 27 21:55:26 2017 +0200 $ Plugins: 201708271955 https://github.com/OpenSmalltalk/opensmalltalk-vm.git $ Linux testing-gce-7a972a8a-3d5e-4b8d-94e0-6252bfe9a477 3.13.0-115-generic #162~precise1-Ubuntu SMP Fri Mar 24 16:47:06 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux plugin path: /home/alistair/pharo7/vm64/pharo-vm/lib/pharo/5.0-201708271955 [default: /home/alistair/pharo7/vm64/pharo-vm/lib/pharo/5.0-201708271955/] Thanks very much, Alistair