gccrs: fix(type-check): Resolve 'exceptional' error_mark in visit pattern compilation #4376
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Harishankar14
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I'm not 100% confident because I'm not too familiar with that part of the codebase but it feels like you're trying here to fix the symptoms rather than the source of the problem.
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The compiler was throwing an ICE when a Type Alias was used as a value in a LetStmt (e.g., `let () = ::X = ();`). This occurred because the backend pattern compiler received an `error_mark_node` for the initialization expression and failed to handle it. This patch adds a check in `CompileStmt` to detect if the initialization expression is an `error_mark_node`. To prevent regression failures in other tests (excess errors), this check is restricted specifically to `TuplePattern`, which was the source of the crash. If detected, we now emit a proper error message and exit early. Fixes Rust-GCC#4161 gcc/rust/ChangeLog: * backend/rust-compile-stmt.cc (CompileStmt::visit): Check for error_mark_node in init expression for TuplePatterns and exit early if found. gcc/testsuite/ChangeLog: * rust/compile/issue-4161.rs: New test. Signed-off-by: Harishankar P P <[email protected]>
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This patch fixes two Internal Compiler Errors (ICEs) encountered during compilation.
First, it resolves a crash in
CompilePatternLet::visitwhere the backend panicked upon encountering anerror_marknode within a tuple pattern. A check was added to handle erroneous types gracefully.Second, it fixes a crash in the
MarkLivelint pass. Previously, visiting aTypeAliascould triggerrust_unreachable()if the AST-to-HIR mapping lookup failed. This assertion has been removed to allow the compiler to continue execution when the mapping is missing.Fixes #4161
gcc/rust/ChangeLog:
gcc/testsuite/ChangeLog:
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