ICE on match expression without any match arms

[MahadMuhammad]

ICE - match statement having no match arms

• You can view the same on compiler-explorer

---

Code

enum Empty {}

fn foo(x: Empty) {
    match x {
        // empty
    }
}

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Meta

• What version of Rust GCC were you using, git sha 95dcbb2
• gccrs (Compiler-Explorer-Build-gcc-dba8bc5bf8247161b6eff4f738b6479382f770f2-binutils-2.40) 13.0.1 20230417 (experimental)

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Error output

• Internal Compiler Error.

Backtrace

➜  gccrs-build gcc/crab1 ../mahad-testsuite/E0002.rs
crab1: internal compiler error: in check_match_scrutinee, at rust/backend/rust-compile-expr.cc:1286
0x7c6897 check_match_scrutinee
  ../../gccrs/gcc/rust/backend/rust-compile-expr.cc:1286
0xcc7d7b Rust::Compile::CompileExpr::visit(Rust::HIR::MatchExpr&)
  ../../gccrs/gcc/rust/backend/rust-compile-expr.cc:1314
0xcbd394 Rust::Compile::CompileExpr::Compile(Rust::HIR::Expr*, Rust::Compile::Context*)
  ../../gccrs/gcc/rust/backend/rust-compile-expr.cc:45
0xce5194 Rust::Compile::HIRCompileBase::compile_function_body(tree_node*, Rust::HIR::BlockExpr&, Rust::TyTy::BaseType*)
  ../../gccrs/gcc/rust/backend/rust-compile-base.cc:487
0xce71fe Rust::Compile::HIRCompileBase::compile_function(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Rust::HIR::SelfParam&, std::vector<Rust::HIR::FunctionParam, std::allocator<Rust::HIR::FunctionParam> >&, Rust::HIR::FunctionQualifiers const&, Rust::HIR::Visibility&, std::vector<Rust::AST::Attribute, std::allocator<Rust::AST::Attribute> >&, unsigned int, Rust::HIR::BlockExpr*, Rust::Resolver::CanonicalPath const*, Rust::TyTy::FnType*)
  ../../gccrs/gcc/rust/backend/rust-compile-base.cc:643
0xcbac68 Rust::Compile::CompileItem::visit(Rust::HIR::Function&)
  ../../gccrs/gcc/rust/backend/rust-compile-item.cc:181
0xac42f9 Rust::Compile::CompileItem::compile(Rust::HIR::Item*, Rust::Compile::Context*, Rust::TyTy::BaseType*, bool, unsigned int)
  ../../gccrs/gcc/rust/backend/rust-compile-item.h:38
0xac42f9 Rust::Compile::CompileCrate::go()
  ../../gccrs/gcc/rust/backend/rust-compile.cc:47
0xac4348 Rust::Compile::CompileCrate::Compile(Rust::HIR::Crate&, Rust::Compile::Context*)
  ../../gccrs/gcc/rust/backend/rust-compile.cc:40
0xabe37d Rust::Session::compile_crate(char const*)
  ../../gccrs/gcc/rust/rust-session-manager.cc:671
Please submit a full bug report, with preprocessed source (by using -freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

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[powerboat9]

It seems like matching on zero-variant enums isn't supported yet, and any attempt to do so fails an assertion.