CPython 3.14.2 Build Failure

Bug report

Bug description

I ran the configure script to build the experimental JIT compiler, but have it be disabled by default, and the JIT compiler and therefore CPython won't build.

$ ../configure --enable-framework="$HOME/Library/Frameworks" --enable-optimizations --with-lto --enable-safety --enable-experimental-jit=yes-off --enable-ipv6=yes --with-system-libmpdec --with-pydebug
$ gmake
...
python3 ../Tools/jit/build.py aarch64-apple-darwin24.6.0 --output-dir . --pyconfig-dir . --cflags="" --debug
Traceback (most recent call last):
  File "/private/tmp/Python-3.14.2/build/../Tools/jit/build.py", line 8, in <module>
    import _targets
  File "/private/tmp/Python-3.14.2/Tools/jit/_targets.py", line 287
    match relocation:
          ^
SyntaxError: invalid syntax
gmake[2]: *** [Makefile:3287: jit_stencils.h] Error 1
gmake[2]: Leaving directory '/private/tmp/Python-3.14.2/build'
gmake[1]: *** [Makefile:1006: profile-gen-stamp] Error 2
gmake[1]: Leaving directory '/private/tmp/Python-3.14.2/build'
gmake: *** [Makefile:1018: profile-run-stamp] Error 2

CPython versions tested on

3.14.2

Operating systems tested on

macOS Sequoia 15.7.4 (Apple Silicon)

[johnslavik]

You seem to be using Python <3.10 somehow?
This match would be illegal only in such case.
What does your python3 --version show? Maybe you can update it to 3.10+?

You seem to be using Python <3.10 somehow? This match would be illegal only in such case. What does your python3 --version show? Maybe you can update it to 3.10+?

The Apple-macOS provided python3 is on 3.9.6

% /usr/bin/python3
Python 3.9.6 (default, Apr 30 2025, 02:07:17)
[Clang 17.0.0 (clang-1700.0.13.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()

[skirpichev]

Please see docs:

When building CPython with JIT enabled, ensure that your system has Python 3.11 or later installed.