Skip to content

gh-148501: Disable AArch64 Mach-O LOH for JIT stencils #157040

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
lgeiger wants to merge 2 commits into
base: main
Choose a base branch
from
+10 −1
Open

gh-148501: Disable AArch64 Mach-O LOH for JIT stencils #157040

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
cb5ddfa
gh-148501: Disable AArch64 Mach-O LOH for JIT stencils
lgeiger Sep 6, 2026
df47b12
Add NEWS entry
lgeiger Sep 6, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions Misc/NEWS.d/next/Core_and_Builtins/2026-09-06-16-13-12.gh-issue-148501.a5odxo.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,2 @@
Improve JIT stencils on macOS AArch64 by disabling unused linker
optimization hints.
9 changes: 8 additions & 1 deletion Tools/jit/_targets.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -65,6 +65,7 @@ class _Target(typing.Generic[_S, _R]):
condition: str
_: dataclasses.KW_ONLY
args: typing.Sequence[str] = ()
stencil_args: typing.Sequence[str] = ()
optimizer: type[_optimizers.Optimizer] = _optimizers.Optimizer
label_prefix: typing.ClassVar[str]
symbol_prefix: typing.ClassVar[str]
Expand Down Expand Up @@ -250,6 +251,7 @@ async def _build_stencil_group(
if self.frame_pointers:
args_s += ["-Xclang", "-mframe-pointer=reserved"]
args_s += self._compile_args()
args_s += self.stencil_args
# Allow user-provided CFLAGS to override any defaults
args_s += shlex.split(self.cflags)
await _llvm.run(
Expand Down Expand Up @@ -720,7 +722,12 @@ def get_target(host: str) -> _COFF32 | _COFF64 | _ELF | _MachO:
host = "aarch64-apple-darwin"
condition = "defined(__aarch64__) && defined(__APPLE__)"
optimizer = _optimizers.OptimizerAArch64
target = _MachO(host, condition, optimizer=optimizer)
target = _MachO(
host,
condition,
optimizer=optimizer,
stencil_args=["-mllvm", "-aarch64-enable-collect-loh=false"],
)
elif re.fullmatch(r"aarch64-pc-windows-msvc", host):
host = "aarch64-pc-windows-msvc"
condition = "defined(_M_ARM64)"
Expand Down
Loading