Fix segfault when passing friendly tangents to "non-friendly" forward cache in 1.10 and formatting

[gdalle]

#980 was merged before formatting passed

[codecov]

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[gdalle]

@Technici4n the segfault is happening again, no clue why

[gdalle]

Here's the MWE for the segfault. It happens when we try to use value_and_derivative!! with friendly tangent types even though the cache was not prepared for that:

using Mooncake: Config, zero_tangent, prepare_derivative_cache, value_and_derivative!!

struct SimplePair
    x1::Float64
    x2::Float64
end

f = (x, y) -> x * y + cos(x)
g = (sp::SimplePair) -> SimplePair(f(sp.x1, sp.x2), 2.0)

x, y = 5.0, 4.0
dx, dy = 3.0, 2.0

fx_sp = (g, SimplePair(x, y))
dfx_sp = (zero_tangent(g), SimplePair(dx, dy))

cache_sp_friendly = prepare_derivative_cache(
    fx_sp...; config=Config(; friendly_tangents=true)
)
value_and_derivative!!(cache_sp_friendly, zip(fx_sp, dfx_sp)...)  # works

cache_sp_unfriendly = prepare_derivative_cache(
    fx_sp...; config=Config(; friendly_tangents=false)
)
value_and_derivative!!(cache_sp_unfriendly, zip(fx_sp, dfx_sp)...)  # segfaults on 1.10 only

[Technici4n]

Is the segfault maybe coming from calling an opaque closure with argument types that don't match the signature? Then it should hopefully go away with debug_mode=true.

[gdalle]

Is the segfault maybe coming from calling an opaque closure with argument types that don't match the signature? Then it should hopefully go away with debug_mode=true.

Maybe that was the root cause, I got it to go away by manually checking that the tangent types match the primal types inside provided Dual numbers. Not sure why this isn't done inside the Dual constructor, probably because of partially initialized structs?

[gdalle]

Are we good vis-a-vis failing tests?

[Technici4n]

Yes, good. Same failures as the Mooncake 0.5 PR + a spurious rules/blas_level_3-1.12-x64 failure.

[Technici4n]

Thank you for the quick fixup, let's get this released!