Supported platforms and architectures¶

Supported architectures¶

Well supported architectures:

• Intel x86 (32-bit) and x86_64 (64-bit, aka AMD64)

Best effort support architectures:

• ppc64le: should be well supported in practice

• AArch64

• ARMv7: should be well supported in practice

• s390x

Well supported platforms¶

Well supported platforms on Python 3.7 and 2.7:

• Linux

• Windows 8 and newer for Python 3.9

• FreeBSD 10 and newer

• macOS Snow Leopard (macOS 10.6, 2008) and newer

It took 9 years to fix all compiler warnings on Windows 64-bit! Usually, the fix was to use a larger type to avoid a downcast. For example replace int with Py_ssize_t.

Best effort and unofficial platforms¶

Supported platform with best effort support:

• Android API 24

• OpenBSD

• NetBSD

• AIX 6.1 and newer

Platforms not supported officially:

• Cygwin

• HP-UX

  • HP-UX 11i v3 was first released in 2007. Latest HP-UX release: May 2020.

  • test_gdb fix in 2020: commit b2dca49ca3769cb60713f5c2b43e5d5bbdc1f9c7

  • os.chroot fix in 2020: commit a9edf44a2de9b23a1690b36cdfeed7b41ab763bd

• MinGW

• Solaris, OpenIndiana

Unofficial projects:

• Python for OpenVMS

• PythonD: PythonD is a 32-bit, multi-threaded, networking- and OpenGL-enabled Python interpreter for DOS and Windows.

Removed platforms¶

PEP 11 lists removal of supported platforms:

• Platforms without threading support removed in Python 3.7

  • https://bugs.python.org/issue31370

  • https://mail.python.org/pipermail/python-dev/2017-September/149156.html

  • https://github.com/python/cpython/commit/a6a4dc816d68df04a7d592e0b6af8c7ecc4d4344

• BSD/OS, 2017:

  • https://bugs.python.org/issue31624

  • https://github.com/python/cpython/commit/288d1daadaddf6ae35cf666138ba4b5d07449657

• MS-DOS: 2014: bpo-22591: Drop support of MS-DOS (DJGPP compiler), commit b71c7dc9

• Python 3.4: VMS, OS/2, Windows 2000

  • VMS: bpo-16136: Removal of VMS support, main removal commit (remove VMSError doc commit)

• IRIX (“The last major version of IRIX is IRIX 6.5, which was released in May 1998”)

  • Python 3.7: Remove dynload_dl (2020)

• AIX 5.3 and below

• Mac OS 9:

  • MacOS 9 dropped in Python 2.4 (see PEP 11)

  • bpo-35346: Drop Mac OS 9 support from platform

  • bpo-35471: Remove the macpath module (GH-11129)

I want CPython to support my platform!¶

In short, there are 2 conditions:

• the full test suite have to pass (./python -m test succeess)

• a CPython core developer has to be responsible of the platform to fix issues specific to this platform on CIs.

If it’s not possible, the best option is to maintain a fork of CPython (fork of the Git repository) to maintain patches to top of the master branch (and maybe also patches on other branches).

More detail in the PEP 11.

C compilers¶

Python has a good support for:

• GCC

• clang

• Visual Studio MSC

Best effort:

• XLC on AIX 7

Compiler flags:

• Debug build uses -Og

• Release build uses -O3

• clang with LTO

• clang with LTO+PGO

• GCC with LTO

• GCC with LTO+PGO

See Python Continuous Integration to see exactly which C compilers and which compiler and linker flags are actually tested.

See also Python builds.

See PEP 7 for the minimum C standard version. In short, it’s a subset of C99 with static line functions and <stdint.h>.

sys.platform versus os.name¶

Example of sys.platform and os.name values:

sys.platform comes from the MACHDEP variable which is built by the configure script using:

• uname -s command output converted to lowercase, with some special rules (ex: linux3 is replaced with linux on Python 3)

• uname -r command output (or uname -v UnixWare or OpenUNIX)

• $host variable (./configure --host=xxx parameter) when cross-compiling

(*) sys.platform was also linux3 on old versions of Python 2.6 and Python 2.7 with Linux kernel 3.x.

(**) On AIX sys.platform included a release digit, aix3, …, aix7 on all versions of Python through version Python 3.7.