segfault in expand_decl_macro with empty feature gat... | Rust-GCC/gccrs

Nobody has claimed this yet.

auto-reduced (treereduce-rust):

//@compile-flags: -frust-incomplete-and-experimental-compiler-do-not-use
macro_rules! make_macro {
    ($macro_name:ident $($matcher:tt)*) => {
        #[feature]
        macro_rules! $macro_name {
            (<=  =>) => {};
        }
    };
}

make_macro!(interpolations type $($i:ident)::* + $e:expr);
interpolations!(<= type foo::bar + x.sort() =>);

original:

//@compile-flags: -frust-incomplete-and-experimental-compiler-do-not-use
macro_rules! make_macro {
    ($macro_name:ident $($matcher:tt)*) => {
        #[feature]
        macro_rules! $macro_name {
            (<=  =>) => {};
        }
    };
}

make_macro!(interpolations type $($i:ident)::* + $e:expr);
interpolations!(<= type foo::bar + x.sort() =>);

Version information:

5dc8c4d20d62462ebce137c6e5146235ab9e9e2e

Command:
/home/matthias/vcs/github/gccrs/gccrs-build/gcc/crab1 -frust-incomplete-and-experimental-compiler-do-not-use

Program output

/tmp/icemaker_global_tempdir.AGJ5RW194Exn/rustc_testrunner_tmpdir_reporting.0pZVUqrltOVl/mvce.rs:3:11: error: macro not found
    3 |         #[feature]
      |           ^~~~~~~
crab1: internal compiler error: Segmentation fault
0x2fecaf8 internal_error(char const*, ...)
	../../gcc/diagnostic-global-context.cc:517
0x196d57f crash_signal
	../../gcc/toplev.cc:321
0xdddcc0 Rust::MacroExpander::expand_decl_macro(unsigned long, Rust::AST::MacroInvocData&, Rust::AST::MacroRulesDefinition&, Rust::AST::InvocKind)
	../../gcc/rust/expand/rust-macro-expand.cc:43
0xddedf5 Rust::MacroExpander::expand_invoc(Rust::AST::MacroInvocation&, Rust::AST::InvocKind)
	../../gcc/rust/expand/rust-macro-expand.cc:309
0xea014c void Rust::ExpandVisitor::expand_macro_children<std::vector<std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> >, std::allocator<std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> > > >, std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> > >(std::vector<std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> >, std::allocator<std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> > > >&, std::function<std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> > (Rust::AST::SingleASTNode)>)
	../../gcc/rust/expand/rust-expand-visitor.h:131
0xea014c Rust::ExpandVisitor::expand_inner_items(std::vector<std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> >, std::allocator<std::unique_ptr<Rust::AST::Item, std::default_delete<Rust::AST::Item> > > >&)
	../../gcc/rust/expand/rust-expand-visitor.cc:239
0xda39b3 Rust::Session::expansion(Rust::AST::Crate&, Rust::Resolver2_0::NameResolutionContext&)
	../../gcc/rust/rust-session-manager.cc:958
0xdb8ed7 Rust::Session::compile_crate(char const*)
	../../gcc/rust/rust-session-manager.cc:620
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.

Reproduce the crash with the reduced /tmp/im/2/a.rs input and the listed compiler flag, then start at gcc/rust/expand/rust-macro-expand.cc:43 using the provided backtrace. Trace the empty feature-gate macro expansion and verify that the compiler reports the error without a segmentation fault.

Written by the indexing model from the issue text.

segfault in expand_decl_macro with empty feature gate inside macor

Description

Contributor guide

First steps

Research direction

Assessment