linker __rust_probestack fix

[andrei-marinica]

Fixed the linker issue on Linux, related to probestack.

This issue appears for Rust compilers newer than 1.89, and was fixed in Wasmer 6.1.0.

[Copilot]

Pull request overview

This PR updates the Rust toolchain from version 1.59 to 1.90 and fixes a linker issue related to __rust_probestack on Linux that appeared in Rust compilers newer than 1.89. The fix involves conditionally including a custom probestack implementation when the Rust standard library doesn't provide __rust_probestack.

Changes:

• Updated Rust toolchain to version 1.90
• Added build-time detection for missing __rust_probestack using rustversion crate
• Included fallback probestack implementation from rust-lang/compiler-builtins

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
rust-toolchain	Updated Rust version from 1.59 to 1.90
lib/vm/build.rs	New build script that conditionally sets missing_rust_probestack cfg flag for Rust >= 1.89
lib/vm/Cargo.toml	Added rustversion 1.0 build dependency
lib/vm/src/probestack/mod.rs	Added conditional compilation logic to use custom probestack when needed
lib/vm/src/probestack/compiler_builtins.rs	New file containing probestack implementation from rust-lang/compiler-builtins
Cargo.lock	Updated dependencies including rustversion and many transitive dependency updates

Comments suppressed due to low confidence (1)

lib/vm/src/probestack/mod.rs:75

• The nested cfg_if blocks with redundant conditions create unnecessary complexity. The inner cfg_if at line 63 checks for not(missing_rust_probestack) and missing_rust_probestack when these are mutually exclusive. This could be simplified by removing the nested cfg_if and using a single if-else construct, or by ensuring better organization of the conditional compilation logic.

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[andrei-marinica]

Branched off from the wrong place. The correct PR is: #38