GH-137218: Fix unnecessary recompile of Programs/_freeze_module

[savannahostrowski]

As @encukoupointed out, running make twice after merging #139170 resulted in an unnecessary recompile. I believe this is because of a redundant assignment of JIT_STENCILS_H.

• Issue: Main segfaults importing _pyrepl with low value for JUMP_BACKWARD_INITIAL_VALUE #137218

[savannahostrowski]

!buildbot FreeBSD

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @savannahostrowski for commit 9e4b457 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F139241%2Fmerge

The command will test the builders whose names match following regular expression: FreeBSD

The builders matched are:

• AMD64 FreeBSD Refleaks PR
• AMD64 FreeBSD15 PR
• AMD64 FreeBSD PR
• AMD64 FreeBSD14 PR

[savannahostrowski]

!buildbot FreeBSD

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @savannahostrowski for commit 70d5a56 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F139241%2Fmerge

The command will test the builders whose names match following regular expression: FreeBSD

The builders matched are:

• AMD64 FreeBSD Refleaks PR
• AMD64 FreeBSD15 PR
• AMD64 FreeBSD PR
• AMD64 FreeBSD14 PR

[savannahostrowski]

@encukou Did you want to take a look at this one?

[encukou]

Sorry, I missed the notification!

Unfortunately this doesn't solve the issue for me. In my config, REGEN_JIT_COMMAND is empty, so a jit_stencils.h is never created, but make attempts to create it and recreates its dependents (jit_stencils.h → Python/jit.o → Programs/_freeze_module → frozen modules).

[savannahostrowski]

Okay, I think that removing the literal jit_stencils.h dependency fixes this. This should also still work just fine to solve the original problem since the platform-specific stencils always exist alongside jit_stencils.h.

[encukou]

That did it. Thank you!