Add support for freethreaded builds of Python 3.13 #326

zanieb · 2024-09-09T14:31:58Z

Closes #320

There are a couple important notes here:

We exceeded the GitHub matrix size limit in the Linux build so the 3.13 jobs were split out into a separate matrix.
There is no support for freethreaded musl builds because freethreading requires mimalloc which requires stdatomic which is not available in the much older LLVM we are using there. I am working on upgrading those to LLVM 18 separately.

zanieb · 2024-09-09T14:33:31Z

.github/workflows/apple.yml

-            optimizations: 'debug'
+            options: 'debug'


Initially I added a separate freethreaded: true flag but defining all the build options at once makes passing them around much easier.

I wonder if this should be variant? Or flavor, as they're called in the docs? Don't feel strongly.

Per the documentation, this isn't the "flavor" it's the "build configuration". The "flavors" are install_only / full. These are options to configure the build.

Instead of --options and build_options we could do --config and build_config but I don't think that's clearer.

zanieb · 2024-09-09T14:34:26Z

cpython-unix/build-cpython.sh

+if [ -n "${CPYTHON_FREETHREADED}" ]; then
+    CONFIGURE_FLAGS="${CONFIGURE_FLAGS} --disable-gil"
+fi


This is the "key" change.

…m limit

zanieb · 2024-09-26T01:29:30Z

Notes on failures

Resolved issues

build-313 (x86_64_v4-unknown-linux-musl, cpython-3.13, lto)
build-313 (x86_64_v3-unknown-linux-musl, cpython-3.13, lto, true)
build (x86_64_v4-unknown-linux-musl, cpython-3.9, lto)

cpython-3.13> /tools/host/bin/ld: warning: libcrypto-lib-x86_64-gf2m.o: missing .note.GNU-stack section implies executable stack
cpython-3.13> /tools/host/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
cpython-3.13> /tools/host/bin/ld: warning: libcrypto-lib-x86_64-gf2m.o: missing .note.GNU-stack section implies executable stack
cpython-3.13> /tools/host/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
cpython-3.13> /tools/host/bin/ld: /tools/llvm/lib/clang/14.0.3/lib/linux/libclang_rt.profile-x86_64.a(InstrProfilingFile.c.o): in function `parseAndSetFilename':
cpython-3.13> InstrProfilingFile.c:(.text.parseAndSetFilename+0xf9): undefined reference to `__strdup'
cpython-3.13> clang-14: error: linker command failed with exit code 1 (use -v to see invocation)
cpython-3.13> make[2]: *** [Programs/_testembed] Error 1
cpython-3.13> Makefile:1531: recipe for target 'Programs/_testembed' failed
cpython-3.13> make[2]: *** Waiting for unfinished jobs....
cpython-3.13> /tools/host/bin/ld: /tools/llvm/lib/clang/14.0.3/lib/linux/libclang_rt.profile-x86_64.a(InstrProfilingFile.c.o): in function `parseAndSetFilename':
cpython-3.13> InstrProfilingFile.c:(.text.parseAndSetFilename+0xf9): undefined reference to `__strdup'
cpython-3.13> clang-14: error: linker command failed with exit code 1 (use -v to see invocation)

build-313 (x86_64_v4-unknown-linux-gnu, cpython-3.13, freethreaded+lto)

cpython-3.13> # Next, run the profile task to generate the profile information.
cpython-3.13> LLVM_PROFILE_FILE="/build/Python-3.13.0rc2/code-%p.profclangr" LD_LIBRARY_PATH=/build/Python-3.13.0rc2 ./python -m test --pgo --timeout=
cpython-3.13> Illegal instruction (core dumped)
cpython-3.13> Makefile:845: recipe for target 'profile-run-stamp' failed

build-313 (ppc64le-unknown-linux-gnu, cpython-3.13, freethreaded+lto)
build-313 (aarch64-unknown-linux-gnu, cpython-3.13, freethreaded+lto)

cpython-3.13> # Next, run the profile task to generate the profile information.
cpython-3.13> LD_LIBRARY_PATH=/build/Python-3.13.0rc2 ./python -m test --pgo --timeout=
cpython-3.13> /bin/sh: 1: ./python: Exec format error
cpython-3.13> Makefile:845: recipe for target 'profile-run-stamp' failed

All the LTO failures are addressed by 0a53b06 which was a mistake in the options refactor.

build-313 (x86_64_v4-unknown-linux-musl, cpython-3.13, freethreaded+debug
build-313 (x86_64_v4-unknown-linux-musl, cpython-3.13, freethreaded+noopt)
build-313 (x86_64_v2-unknown-linux-musl, cpython-3.13, freethreaded+lto, true)
build-313 (x86_64-unknown-linux-musl, cpython-3.13, freethreaded+debug, true)

cpython-3.13> checking for builtin __atomic_load_n and __atomic_store_n functions...
cpython-3.13> yes
cpython-3.13> checking for --with-mimalloc...
cpython-3.13> configure: error: mimalloc requires stdatomic.h, use --without-mimalloc to disable mimalloc.

The musl builds are still on LLVM 14 which doesn't have C11 support as far as I can tell — we need to upgrade it to unblock. However, this is relatively low-priority since the musl builds are generally unusable (they don't allow loading Python extension modules).

I disabled them in a01c634

We will work on these separately

konstin · 2024-09-26T17:03:00Z

cpython-unix/build-cpython.sh

+if [ -n "${CPYTHON_FREETHREADED}" ]; then
+    PYTHON_BINARY_SUFFIX=t
+    PYTHON_LIB_SUFFIX=t
 else
    PYTHON_BINARY_SUFFIX=
+    PYTHON_LIB_SUFFIX=
+fi
+if [ -n "${CPYTHON_DEBUG}" ]; then
+    PYTHON_BINARY_SUFFIX="${PYTHON_BINARY_SUFFIX}d"
 fi


I think we should do flag in lexicographic order, at least i remember them being in this order, even if the PEP doesn't talk about order. I tried to to look in cpython but didn't find anything about order either.

huh sys.abiflags say td too

This ordering matches the order that is produced by CPython; we're not choosing the order, we're just constructing these variables to pull artifacts from the builds.

charliermarsh · 2024-09-26T18:34:44Z

cpython-unix/build-main.py

-        "--optimizations",
-        choices={"debug", "noopt", "pgo", "lto", "pgo+lto"},
+        "--options",
+        choices=optimizations.union({f"freethreaded+{o}" for o in optimizations}),


Nit: I might just construct this inline on line 56, rather than splitting the construction between there and here.

It seems a bit annoying to construct in one line. Are you suggesting I just enumerate them all manually?

I was suggesting:

optimizations = {"debug", "noopt", "pgo", "lto", "pgo+lto"} optimizations = optimizations.union({f"freethreaded+{o}" for o in optimizations}) parser.add_argument(..., choices=optimizations)

Ah thanks for clarifying. It'd be options = optimizations.union(...) and I'm hesitant to introduce another local variable (basically just personal preference).

charliermarsh · 2024-09-26T18:35:39Z

cpython-windows/build.py

    msvc_version: str,
    windows_sdk_version: str,
    openssl_archive,
    libffi_archive,
    openssl_entry: str,
 ) -> pathlib.Path:
-    pgo = profile == "pgo"
+    parsed_build_options = set(build_options.split("+"))


Was this wrong before? Or was it just never called with pgo+lto?

Ah there are only "pgo" builds on Windows. I just changed this for consistency.

See https://github.com/indygreg/python-build-standalone/pull/326/files#r1777582385

Yeah this seems like a good change.

zanieb · 2024-09-26T18:44:17Z

cpython-windows/build.py

+    # TODO: Rename this to `--options` to match the Unix build script
+    optimizations = {"debug", "noopt", "pgo", "lto", "pgo+lto"}
    parser.add_argument(
-        "--profile",
-        choices={"noopt", "pgo"},
+        "--options",
+        choices=optimizations.union({f"freethreaded+{o}" for o in optimizations}),
        default="noopt",
-        help="How to compile Python",
+        help="Build options to apply when compiling Python",
    )


Two things to follow up on here

I renamed this, I should remove the stale comment.

I added more optimization types here, that's wrong I should remove the other options.

(Hesitant to do that in this pull request unless there are other changes since it takes so long to do builds)

diff --git a/cpython-windows/build.py b/cpython-windows/build.py index 3425a3b..92bca7d 100644 --- a/cpython-windows/build.py +++ b/cpython-windows/build.py @@ -1863,8 +1863,7 @@ def main() -> None: default="cpython-3.11", help="Python distribution to build", ) - # TODO: Rename this to `--options` to match the Unix build script - optimizations = {"debug", "noopt", "pgo", "lto", "pgo+lto"} + optimizations = {"noopt", "pgo"} parser.add_argument( "--options", choices=optimizations.union({f"freethreaded+{o}" for o in optimizations}),

These were unintentionally expanded in #326

zanieb commented Sep 9, 2024

View reviewed changes

Add support for freethreaded builds of Python 3.13

8f9eea7

zanieb force-pushed the zb/3.13t branch from 3f25de7 to 8f9eea7 Compare September 9, 2024 17:11

zanieb added 2 commits September 9, 2024 16:48

Split the 3.13 matrix into another job to get past the 256 matrix ite…

c82c04d

…m limit

Add build_options to the JSON schema

79b56d0

zanieb force-pushed the zb/3.13t branch from 0d87010 to 79b56d0 Compare September 9, 2024 21:11

zanieb added 3 commits September 9, 2024 22:20

Expect version 8 in the JSON schema

f2524fe

Allow freethreaded libpython during validation on macOS

a361bb8

Allow freethreaded libpython during validation on Linux

1e6e587

zanieb mentioned this pull request Sep 23, 2024

Allow creating venv with free-threaded python builds astral-sh/uv#7431

Merged

zanieb added 2 commits September 25, 2024 12:24

Enable mimalloc

16b6b22

Include t in abiflags patch for free-threaded builds

ad4d435

This comment was marked as outdated.

Sign in to view

zanieb added 2 commits September 25, 2024 20:33

Fix mistaken toggle of CPYTHON_OPTIMIZED for LTO builds

0a53b06

Disable freethreaded musl builds

a01c634

We will work on these separately

zanieb marked this pull request as ready for review September 26, 2024 12:04

konstin reviewed Sep 26, 2024

View reviewed changes

charliermarsh reviewed Sep 26, 2024

View reviewed changes

charliermarsh approved these changes Sep 26, 2024

View reviewed changes

zanieb commented Sep 26, 2024

View reviewed changes

zanieb merged commit 0d7e5e0 into main Sep 26, 2024
333 checks passed

zanieb added a commit that referenced this pull request Sep 26, 2024

Remove extra Windows build options

1efc4a2

These were unintentionally expanded in #326

zanieb mentioned this pull request Sep 26, 2024

Remove extra Windows build options #332

Merged

zanieb added a commit that referenced this pull request Sep 26, 2024

Remove extra Windows build options (#332)

ad49e1f

These were unintentionally expanded in #326

vfdev-5 mentioned this pull request Oct 2, 2024

Added arg for free threading support bazelbuild/rules_python#2129

Closed

pitrou mentioned this pull request Oct 8, 2024

[Python] Support for the free-threaded build of CPython 3.13 apache/arrow#43536

Closed

11 tasks

zanieb mentioned this pull request Oct 15, 2024

Fix freethreaded include on Windows #368

Merged

zanieb mentioned this pull request Nov 13, 2024

Require mimalloc explicitly on all GNU Python 3.13 builds #391

Merged

lalten mentioned this pull request Dec 2, 2024

Unknown platform: aarch64-apple-darwin-freethreaded with Bazel 8.0.0rc4 jvolkman/rules_pycross#128

Open

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Add support for freethreaded builds of Python 3.13 #326

Add support for freethreaded builds of Python 3.13 #326

zanieb commented Sep 9, 2024 •

edited

Loading

zanieb Sep 9, 2024

charliermarsh Sep 26, 2024

zanieb Sep 26, 2024 •

edited

Loading

zanieb Sep 9, 2024

This comment was marked as outdated.

zanieb commented Sep 26, 2024 •

edited

Loading

konstin Sep 26, 2024

konstin Sep 26, 2024 •

edited

Loading

zanieb Sep 26, 2024

charliermarsh Sep 26, 2024

zanieb Sep 26, 2024

charliermarsh Sep 26, 2024

zanieb Sep 26, 2024

charliermarsh Sep 26, 2024

zanieb Sep 26, 2024 •

edited

Loading

charliermarsh Sep 26, 2024

zanieb Sep 26, 2024

zanieb Sep 26, 2024

zanieb Sep 26, 2024

Add support for freethreaded builds of Python 3.13 #326

Add support for freethreaded builds of Python 3.13 #326

Conversation

zanieb commented Sep 9, 2024 • edited Loading

Choose a reason for hiding this comment

Choose a reason for hiding this comment

zanieb Sep 26, 2024 • edited Loading

Choose a reason for hiding this comment

Choose a reason for hiding this comment

This comment was marked as outdated.

zanieb commented Sep 26, 2024 • edited Loading

Choose a reason for hiding this comment

konstin Sep 26, 2024 • edited Loading

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

zanieb Sep 26, 2024 • edited Loading

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

zanieb commented Sep 9, 2024 •

edited

Loading

zanieb Sep 26, 2024 •

edited

Loading

zanieb commented Sep 26, 2024 •

edited

Loading

konstin Sep 26, 2024 •

edited

Loading

zanieb Sep 26, 2024 •

edited

Loading