Support #[rustc_align_static] inside thread_local!

[Jules-Bertholet]

Tracking issue: #146177

thread_local! {
    #[rustc_align_static(64)]
    static SO_ALIGNED: u64 = const { 0 };
}

This increases the amount of recursion the macro performs (once per attribute in addition to the previous once per item), making it easier to hit the recursion limit. I’ve added workarounds to limit the impact in the case of long doc comments, but this still needs a crater run just in case.

r? libs

@rustbot label A-attributes A-macros A-thread-locals F-static_align T-libs

Blocked on #146178; @rustbot blocked

[rustbot]

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[rustbot]

Some changes occurred in compiler/rustc_attr_parsing

cc @jdonszelmann

Some changes occurred in compiler/rustc_codegen_gcc

cc @antoyo, @GuillaumeGomez

Some changes occurred to the CTFE machinery

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Some changes occurred to the CTFE / Miri interpreter

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Some changes occurred in compiler/rustc_passes/src/check_attr.rs

cc @jdonszelmann

Some changes occurred to the CTFE / Miri interpreter

cc @rust-lang/miri

The Miri subtree was changed

cc @rust-lang/miri