8 ms·

Win32 on macOS

486 points by yarapavan 7y ago

nly 7y ago
> It also relies on a new feature of macOS Catalina to allow the creation of 32-bit code segments in a 64-bit process Is this roughly equivalent to MAP_32BIT on Linux? http://man7.org/linux/man-pages/man2/mmap.2.html http://man7.org/linux/man-pages/man2/mmap.2.html
- burfog 7y ago
  No, it is like modify_ldt on Linux. http://man7.org/linux/man-pages/man2/modify_ldt.2.html http://man7.org/linux/man-pages/man2/modify_ldt.2.html
skunkworker 7y ago
Okay that’s just impressive. I was wondering how they would adapt for 32bit support on Catalina.
deleted 7y ago
[deleted]
kccqzy 7y ago
> Speaking of code segments, the big thing that Catalina provides that enables this all to work is the ability to create 32-bit code segments in a 64-bit process. For that, they enabled the use of i386_set_ldt() in 64-bit processes. The big caveat though, is that this functionality is restricted by System Integrity Protection (SIP). For now, your best bet to get this working for yourself is to disable SIP. (CrossOver doesn't require that, but the mechanism by which we accomplish that is in flux internally to Apple. When it settles down, I'll update this thread.) This is quite curious. Apple inconvenienced so many users by "removing" 32-bit support on Catalina, and then they added support for local descriptor tables? I'm not aware of any use of LDTs on modern systems (except perhaps Chrome for additional sandboxing).
- toyg 7y ago
  Maybe they plan on doing a big show and dance when they “settle” the issues around SIP: “macOS now allows you to run classic apps and games!!!!”
- blinkingled 7y ago
  Apple has some weird history with doing crazy things with 32b/64b stuff just because they can - back in the Intel 64 early days they ran a 64-bit kernel that loaded 32-bit device drivers. I don't know if anyone has still figured out the how and why of it!
  - brigade 7y ago
    They didn’t load 32-bit drivers in a 64-bit kernel; rather they ran a 32-bit kernel that supported 64-bit userspace processes.
    - exikyut 7y ago
      That's even crazier. How and why??
      - wtallis 7y ago
        Apple started working on 64-bit application support back when they were still on PowerPC, where they only had 64-bit for desktop processors, not laptops. Then the first round of Intel Macs had 32-bit Core Duo processors. Less than a year later the second round introduced 64-bit Core 2 Duo processors that were pretty much a drop-in replacement, and at the time it certainly didn't make sense for Apple to overhaul their EFI, kernel and drivers with a 64-bit transition only 9 months after switching from PPC to x86. Support for 64-bit GUI applications on OS X didn't arrive until 2007, a year after Intel Macs started using 64-bit processors. Support for running a 64-bit kernel arrived in 2009, and only for machines that had 64-bit EFI firmware. In 2012, Apple dropped support for the machines that had 64-bit processors but used 32-bit EFI, so from that point on they were handling the 64/32-bit mix the same as other operating systems.
      - 7y ago
joshumax 7y ago
I was only around at Codeweavers for a part of this huge undertaking, and only contributed a small part of the 32-on-64 MacOS patchset, but I must say this was one of the most impressive feats I've seen coordinated using mainly nothing but email and IRC for communication. Everything from thunking layers to calling conventions to inline assembly in the Wine codebase had to be redesigned for this release of Wine; an absolutely massive proposition. Ideas such as dynamic binary translation and running Win32 executables in the MacOS hypervisor framework were considered, and some ideas I tried while hacking Wine gave me insight into other projects I hack on such as Qemu and LLVM. In short; props to everyone who worked on this! It was a long time in the process!
- saagarjha 7y ago
  > nothing but email and IRC But? Those are both extremely capable communication mechanisms.
  - r1nkgrl 7y ago
    Exactly. When people are motivated to work together, even poor communication tools are adequate. But these are excellent communication tools.
  - hoistbypetard 7y ago
    I read "nothing but email and IRC" to mean "without in-person meetings" as opposed to "without more capable communications tools".
    - swiley 7y ago
      Or without voice chat. Although coding over voice/video chat isn’t fun.
- bonzini 7y ago
  > running Win32 executables in the MacOS hypervisor framework Interesting, why was this discarded? Performance reasons? Or the API not being satisfactory?
yitchelle 7y ago
>> ...coordinated using mainly nothing but email and IRC for communication. I wonder what other projects (on a scale larger than your typical side hustle projects) are coordinated via IM chat or email? On the surface, the Linux kernel coordination seems to be coordinated like this, but I am not 100% sure.
- arboghast 7y ago
  When I was at Canonical back in 2007-2008, we were mostly communicating using email and IRC. I had to adapt but ended up finding it very productive.
- throwaway2048 7y ago
  Basically every open source project that isnt "Group of devs at the same company" works like this. Open source projects are likely the largest user of mailing lists.
  - ownagefool 7y ago
    I'd argue it works for devs at the same company quite well, but having asynchronous communication is counter to your average business persons desire to lock you in a room for an hour and make you make a decision.
- dewey 7y ago
  Every open source project that’s reasonable enough not to hide all their communications in proprietary silos like Slack and Discord.
  - jayflux 7y ago
    Ok I’ll bite.. Seeing that both slack and discord save logs from the beginning (which irc doesn’t), isn’t communication less hidden if anything? It’s far easier for someone new to play catch up. There’s a reason large open source projects moved to these (React, Rust, etc).
    - 7y ago
steve19 7y ago
Does apple have a good reason for killing 32bit support? I play a number of games that will now never run without a VM.
- 4ad 7y ago
  My speculation is that it's for the upcoming arm64 transition (yet another speculation). It's easier to make one emulator, than two.
- em500 7y ago
  https://pilky.me/apples-technology-transitions/ https://pilky.me/apples-technology-transitions/ Section "Why Drop 32 Bit?" (last quarter of the article).
  - zmzrr 7y ago
    "when you open a 32 bit app, 32 bit system libraries remain loaded forever!" okay how about you fix that instead?
- musicale 7y ago
  The obvious development reason is to simplify and unify the code base, tools, and build process across all of their platforms. 32-bit bugs can also be ignored/deleted for future versions. The obvious hardware reason on iOS is that Apple can remove support for ARM32. The obvious business reason is to encourage subscriptions to Apple Arcade.
  - jaflo 7y ago
    How is Arcade related to 32-bit?
    - saagarjha 7y ago
      Lots of games are 32-bit.
      - 7y ago
tempodox 7y ago
This is a great feat and it creates a somewhat ironic situation: When I want to run an app on Catalina that happens to be 32-bit only, I'm practically forced to use the Windows version. I can't see how that was a smart move on Apple's side.
- scarface74 7y ago
  Why would Apple cafe if you run Windows on the Mac?
  - IggleSniggle 7y ago
    It weakens your incentive to buy a Mac the next time you purchase a computer if you find yourself forced into a different OS anyway.
    - scarface74 7y ago
      Apple has been offering solutions to run Windows apps for over two decades. First they bundled SoftWindows with early PPC Macs, then they offered hardware Intel daughtercards and they have been bundling Boot Camp since shortly after the Intel Macs were introduced. There is very little important software outside of iOS development software that is Mac only. People who care about backwards compatibility would never buy Macs.
      - wayoutthere 7y ago
        > There is very little important software outside of iOS development software that is Mac only. So true; it feels like every Mac app is Electron these days.
- andai 7y ago
  Could some of the wizardry described here be used to get native 32-bit software working again?
  - 7y ago
Razengan 7y ago
> It also relies on a new feature of macOS Catalina to allow the creation of 32-bit code segments in a 64-bit process. How was this never brought up during all the "Catalina killed 32-bit" pitchforkings? Seems like a very important point, that has enabled the ability to emulate 32-bit apps.
- saagarjha 7y ago
  It’s gated by an undocumented entitlement.
  - 4ad 7y ago
    Since wine is using it, it seems it's not gated enough.
    - saagarjha 7y ago
      I don't think the changes have been upstreamed into Wine. Plus I believe that being able to use the entitlement requires SIP to be disabled.
  - exikyut 7y ago
    I don't know how to mentally parse this sentence. (Not snark; stumped.)
    - kevingadd 7y ago
      "entitlements" are OSX Catalina's new(ish?) permission grants that applications need in order to access certain features like JIT or specific syscalls. The entitlement needed for this feature to work is undocumented. See here: https://developer.apple.com/documentation/bundleresources/entitlements https://developer.apple.com/documentation/bundleresources/en...
      - my123 7y ago
        Entitlements aren't new, they existed since ages (OS X 10.11 already used them quite a bit).
hiruxxv 7y ago
bit.ly/2RRaN2g
hiruxxv 7y ago
http://bit.ly/2RRaN2g http://bit.ly/2RRaN2g
notaplumber 7y ago
Why OpenBSD/amd64 will not, and never has supported 32-bit binary compatibility on 64-bit. https://marc.info/?l=openbsd-misc&m=148926149318522 https://marc.info/?l=openbsd-misc&m=148926149318522
ryuukk_ 7y ago
the cancer wine is coming to macOS... they don't need that, they have a healthly platform and eco-system, stop trying to make macOS a linux distribution, it is not a crapware hackerWanabeOS

486 points by yarapavan 7y ago

nly 7y ago

> It also relies on a new feature of macOS Catalina to allow the creation of 32-bit code segments in a 64-bit process Is this roughly equivalent to MAP_32BIT on Linux? http://man7.org/linux/man-pages/man2/mmap.2.html http://man7.org/linux/man-pages/man2/mmap.2.html

burfog 7y ago
No, it is like modify_ldt on Linux. http://man7.org/linux/man-pages/man2/modify_ldt.2.html http://man7.org/linux/man-pages/man2/modify_ldt.2.html

skunkworker 7y ago

Okay that’s just impressive. I was wondering how they would adapt for 32bit support on Catalina.

deleted 7y ago

[deleted]

kccqzy 7y ago

> Speaking of code segments, the big thing that Catalina provides that enables this all to work is the ability to create 32-bit code segments in a 64-bit process. For that, they enabled the use of i386_set_ldt() in 64-bit processes. The big caveat though, is that this functionality is restricted by System Integrity Protection (SIP). For now, your best bet to get this working for yourself is to disable SIP. (CrossOver doesn't require that, but the mechanism by which we accomplish that is in flux internally to Apple. When it settles down, I'll update this thread.) This is quite curious. Apple inconvenienced so many users by "removing" 32-bit support on Catalina, and then they added support for local descriptor tables? I'm not aware of any use of LDTs on modern systems (except perhaps Chrome for additional sandboxing).

toyg 7y ago
Maybe they plan on doing a big show and dance when they “settle” the issues around SIP: “macOS now allows you to run classic apps and games!!!!”
blinkingled 7y ago
Apple has some weird history with doing crazy things with 32b/64b stuff just because they can - back in the Intel 64 early days they ran a 64-bit kernel that loaded 32-bit device drivers. I don't know if anyone has still figured out the how and why of it!
- brigade 7y ago
  They didn’t load 32-bit drivers in a 64-bit kernel; rather they ran a 32-bit kernel that supported 64-bit userspace processes.
  - exikyut 7y ago
    That's even crazier. How and why??
    - wtallis 7y ago
      Apple started working on 64-bit application support back when they were still on PowerPC, where they only had 64-bit for desktop processors, not laptops. Then the first round of Intel Macs had 32-bit Core Duo processors. Less than a year later the second round introduced 64-bit Core 2 Duo processors that were pretty much a drop-in replacement, and at the time it certainly didn't make sense for Apple to overhaul their EFI, kernel and drivers with a 64-bit transition only 9 months after switching from PPC to x86. Support for 64-bit GUI applications on OS X didn't arrive until 2007, a year after Intel Macs started using 64-bit processors. Support for running a 64-bit kernel arrived in 2009, and only for machines that had 64-bit EFI firmware. In 2012, Apple dropped support for the machines that had 64-bit processors but used 32-bit EFI, so from that point on they were handling the 64/32-bit mix the same as other operating systems.
    - 7y ago

joshumax 7y ago

I was only around at Codeweavers for a part of this huge undertaking, and only contributed a small part of the 32-on-64 MacOS patchset, but I must say this was one of the most impressive feats I've seen coordinated using mainly nothing but email and IRC for communication. Everything from thunking layers to calling conventions to inline assembly in the Wine codebase had to be redesigned for this release of Wine; an absolutely massive proposition. Ideas such as dynamic binary translation and running Win32 executables in the MacOS hypervisor framework were considered, and some ideas I tried while hacking Wine gave me insight into other projects I hack on such as Qemu and LLVM. In short; props to everyone who worked on this! It was a long time in the process!

saagarjha 7y ago
> nothing but email and IRC But? Those are both extremely capable communication mechanisms.
- r1nkgrl 7y ago
  Exactly. When people are motivated to work together, even poor communication tools are adequate. But these are excellent communication tools.
- hoistbypetard 7y ago
  I read "nothing but email and IRC" to mean "without in-person meetings" as opposed to "without more capable communications tools".
  - swiley 7y ago
    Or without voice chat. Although coding over voice/video chat isn’t fun.
bonzini 7y ago
> running Win32 executables in the MacOS hypervisor framework Interesting, why was this discarded? Performance reasons? Or the API not being satisfactory?

yitchelle 7y ago

>> ...coordinated using mainly nothing but email and IRC for communication. I wonder what other projects (on a scale larger than your typical side hustle projects) are coordinated via IM chat or email? On the surface, the Linux kernel coordination seems to be coordinated like this, but I am not 100% sure.

arboghast 7y ago
When I was at Canonical back in 2007-2008, we were mostly communicating using email and IRC. I had to adapt but ended up finding it very productive.
throwaway2048 7y ago
Basically every open source project that isnt "Group of devs at the same company" works like this. Open source projects are likely the largest user of mailing lists.
- ownagefool 7y ago
  I'd argue it works for devs at the same company quite well, but having asynchronous communication is counter to your average business persons desire to lock you in a room for an hour and make you make a decision.
dewey 7y ago
Every open source project that’s reasonable enough not to hide all their communications in proprietary silos like Slack and Discord.
- jayflux 7y ago
  Ok I’ll bite.. Seeing that both slack and discord save logs from the beginning (which irc doesn’t), isn’t communication less hidden if anything? It’s far easier for someone new to play catch up. There’s a reason large open source projects moved to these (React, Rust, etc).
  - 7y ago

steve19 7y ago

Does apple have a good reason for killing 32bit support? I play a number of games that will now never run without a VM.

4ad 7y ago
My speculation is that it's for the upcoming arm64 transition (yet another speculation). It's easier to make one emulator, than two.
em500 7y ago
https://pilky.me/apples-technology-transitions/ https://pilky.me/apples-technology-transitions/ Section "Why Drop 32 Bit?" (last quarter of the article).
- zmzrr 7y ago
  "when you open a 32 bit app, 32 bit system libraries remain loaded forever!" okay how about you fix that instead?
musicale 7y ago
The obvious development reason is to simplify and unify the code base, tools, and build process across all of their platforms. 32-bit bugs can also be ignored/deleted for future versions. The obvious hardware reason on iOS is that Apple can remove support for ARM32. The obvious business reason is to encourage subscriptions to Apple Arcade.
- jaflo 7y ago
  How is Arcade related to 32-bit?
  - saagarjha 7y ago
    Lots of games are 32-bit.
    - 7y ago

tempodox 7y ago

This is a great feat and it creates a somewhat ironic situation: When I want to run an app on Catalina that happens to be 32-bit only, I'm practically forced to use the Windows version. I can't see how that was a smart move on Apple's side.

scarface74 7y ago
Why would Apple cafe if you run Windows on the Mac?
- IggleSniggle 7y ago
  It weakens your incentive to buy a Mac the next time you purchase a computer if you find yourself forced into a different OS anyway.
  - scarface74 7y ago
    Apple has been offering solutions to run Windows apps for over two decades. First they bundled SoftWindows with early PPC Macs, then they offered hardware Intel daughtercards and they have been bundling Boot Camp since shortly after the Intel Macs were introduced. There is very little important software outside of iOS development software that is Mac only. People who care about backwards compatibility would never buy Macs.
    - wayoutthere 7y ago
      > There is very little important software outside of iOS development software that is Mac only. So true; it feels like every Mac app is Electron these days.
andai 7y ago
Could some of the wizardry described here be used to get native 32-bit software working again?
- 7y ago

Razengan 7y ago

> It also relies on a new feature of macOS Catalina to allow the creation of 32-bit code segments in a 64-bit process. How was this never brought up during all the "Catalina killed 32-bit" pitchforkings? Seems like a very important point, that has enabled the ability to emulate 32-bit apps.

saagarjha 7y ago
It’s gated by an undocumented entitlement.
- 4ad 7y ago
  Since wine is using it, it seems it's not gated enough.
  - saagarjha 7y ago
    I don't think the changes have been upstreamed into Wine. Plus I believe that being able to use the entitlement requires SIP to be disabled.
- exikyut 7y ago
  I don't know how to mentally parse this sentence. (Not snark; stumped.)
  - kevingadd 7y ago
    "entitlements" are OSX Catalina's new(ish?) permission grants that applications need in order to access certain features like JIT or specific syscalls. The entitlement needed for this feature to work is undocumented. See here: https://developer.apple.com/documentation/bundleresources/entitlements https://developer.apple.com/documentation/bundleresources/en...
    - my123 7y ago
      Entitlements aren't new, they existed since ages (OS X 10.11 already used them quite a bit).

hiruxxv 7y ago

bit.ly/2RRaN2g

hiruxxv 7y ago

http://bit.ly/2RRaN2g http://bit.ly/2RRaN2g

notaplumber 7y ago

Why OpenBSD/amd64 will not, and never has supported 32-bit binary compatibility on 64-bit. https://marc.info/?l=openbsd-misc&m=148926149318522 https://marc.info/?l=openbsd-misc&m=148926149318522

ryuukk_ 7y ago

the cancer wine is coming to macOS... they don't need that, they have a healthly platform and eco-system, stop trying to make macOS a linux distribution, it is not a crapware hackerWanabeOS