Implement mrb_raise with Rust panic!

.github/workflows/ci.yaml

@@ -28,11 +28,11 @@ jobs:
         shell: bash
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal
+          rustup toolchain install nightly --profile minimal
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv
@@ -70,11 +70,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal --component clippy
+          rustup toolchain install nightly --profile minimal --component clippy
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv
@@ -140,11 +140,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal
+          rustup toolchain install nightly --profile minimal
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv
@@ -177,11 +177,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal --component clippy
+          rustup toolchain install nightly --profile minimal --component clippy
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv
@@ -247,11 +247,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal --component clippy
+          rustup toolchain install nightly --profile minimal --component clippy
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv
@@ -328,11 +328,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal
+          rustup toolchain install nightly --profile minimal
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv
@@ -515,11 +515,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal
+          rustup toolchain install nightly --profile minimal
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv

.github/workflows/crash.yaml

@@ -18,11 +18,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal
+          rustup toolchain install nightly --profile minimal
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv

.github/workflows/spec-state.yaml

@@ -22,11 +22,11 @@ jobs:
       - name: Install Rust toolchain
         run: |
           echo "::group::rustup toolchain install"
-          rustup toolchain install 1.65.0 --profile minimal
+          rustup toolchain install nightly --profile minimal
           echo "::endgroup::"
           echo "::group::set default toolchain"
           rm -rf rust-toolchain
-          rustup default 1.65.0
+          rustup default nightly
           echo "::endgroup::"
           echo "::group::rustup version"
           rustup -Vv

ARCHITECTURE.md

@@ -96,9 +96,9 @@ variables][mruby-globals]. Previous project goals and execution localized mruby
 
 As core APIs and data structures are implemented in _Spinoso_ crates,
 `artichoke-backend` will disable mruby C functions, [reimplement them in
-Rust][artichoke-strangler], and expose `unsafe extern "C" fn` replacements for
-interoperability with the remaining mruby pieces. This process is an application
-of the [Strangler Fig pattern].
+Rust][artichoke-strangler], and expose `unsafe extern "C-unwind" fn`
+replacements for interoperability with the remaining mruby pieces. This process
+is an application of the [Strangler Fig pattern].
 
 [artichoke-backend-docs]:
   https://artichoke.github.io/artichoke/artichoke_backend/

artichoke-backend/README.md

@@ -9,7 +9,7 @@
 `artichoke-backend` crate provides a Ruby interpreter. It currently is
 implemented with [mruby] ABI-compatible bindings, some of which are implemented
 in the vendored mruby C and exported by the [`sys`](src/sys) module, others of
-which are implemented in Rust as `#[no_mangle] unsafe extern "C" fn`.
+which are implemented in Rust as `#[no_mangle] unsafe extern "C-unwind" fn`.
 
 `artichoke-backend` is slowly [strangling] its embedded mruby interpreter by
 reimplementing (oxidizing) the APIs in Rust with Artichoke-sourced components.

artichoke-backend/build.rs

@@ -30,13 +30,14 @@ mod paths {
     }
 
     pub fn bindgen_header() -> PathBuf {
-        crate_root().join("cext").join("bindgen.h")
+        crate_root().join("cext").join("bindgen.hpp")
     }
 }
 
 mod libs {
     use std::env;
     use std::ffi::OsStr;
+    use std::fs;
     use std::path::PathBuf;
     use std::process::{Command, Stdio};
     use std::str;
@@ -95,7 +96,6 @@ mod libs {
             "mrbgems/mruby-class-ext/src/class.c",   // NOTE(GH-32): Pending removal.
             "mrbgems/mruby-compiler/core/codegen.c", // Ruby parser and bytecode generation
             "mrbgems/mruby-compiler/core/y.tab.c",   // Ruby parser and bytecode generation
-            "mrbgems/mruby-error/src/exception.c",   // `mrb_raise`, `mrb_protect`
             "mrbgems/mruby-eval/src/eval.c",         // eval, instance_eval, and friends
             "mrbgems/mruby-fiber/src/fiber.c",       // Fiber class from core, required by `Enumerator`
             "mrbgems/mruby-metaprog/src/metaprog.c", // APIs on Kernel and Module for accessing classes and variables
@@ -117,7 +117,6 @@ mod libs {
         [
             "mrbgems/mruby-class-ext/include", // NOTE(GH-32): Pending removal.
             "mrbgems/mruby-compiler/core",     // Ruby parser and bytecode generation
-            "mrbgems/mruby-error/include",     // `mrb_raise`, `mrb_protect`
             "mrbgems/mruby-eval/include",      // eval, instance_eval, and friends
             "mrbgems/mruby-fiber/include",     // Fiber class from core, required by `Enumerator`
             "mrbgems/mruby-metaprog/include",  // APIs on Kernel and Module for accessing classes and variables
@@ -181,13 +180,18 @@ mod libs {
         let mut build = cc::Build::new();
         build
             .warnings(false)
+            .cpp(true)
+            .flag("-std=c++17")
+            .flag("-x")
+            .flag("c++")
             .define("ARTICHOKE", None)
             .define("MRB_ARY_NO_EMBED", None)
             .define("MRB_GC_TURN_OFF_GENERATIONAL", None)
             .define("MRB_INT64", None)
             .define("MRB_NO_BOXING", None)
             .define("MRB_NO_PRESYM", None)
             .define("MRB_NO_STDIO", None)
+            .define("MRB_USE_CXX_EXCEPTION", None)
             .define("MRB_UTF8_STRING", None);
 
         for source in sources {
@@ -299,16 +303,18 @@ mod libs {
             .arg("--no-doc-comments")
             .arg("--size_t-is-usize")
             .arg("--output")
-            .arg(bindings_out_path)
+            .arg(&bindings_out_path)
             .arg(paths::bindgen_header())
             .arg("--")
+            .arg("-std=c++17")
             .arg("-DARTICHOKE")
             .arg("-DMRB_ARY_NO_EMBED")
             .arg("-DMRB_GC_TURN_OFF_GENERATIONAL")
             .arg("-DMRB_INT64")
             .arg("-DMRB_NO_BOXING")
             .arg("-DMRB_NO_PRESYM")
             .arg("-DMRB_NO_STDIO")
+            .arg("-DMRB_USE_CXX_EXCEPTION")
             .arg("-DMRB_UTF8_STRING");
 
         for include_dir in mruby_include_dirs().chain(mrbsys_include_dirs()) {
@@ -324,6 +330,15 @@ mod libs {
 
         let status = command.status().unwrap();
         assert!(status.success(), "bindgen failed");
+
+        let bindings = fs::read_to_string(&bindings_out_path).unwrap();
+        fs::write(
+            bindings_out_path,
+            bindings
+                .replace(r#"unsafe extern "C" fn"#, r#"unsafe extern "C-unwind" fn"#)
+                .replace(r#"extern "C" {"#, r#"extern "C-unwind" {"#),
+        )
+        .unwrap();
     }
 
     pub fn build(wasm: Option<Wasm>, out_dir: &OsStr) {

artichoke-backend/cext/mrbgems/src/gem_init.c

@@ -4,8 +4,6 @@
 extern "C" {
 #endif
 
-void artichoke_mrbgem_mruby_error_gem_init(mrb_state *);
-void artichoke_mrbgem_mruby_error_gem_final(mrb_state *);
 void artichoke_mrbgem_mruby_eval_gem_init(mrb_state *);
 void artichoke_mrbgem_mruby_eval_gem_final(mrb_state *);
 void artichoke_mrbgem_mruby_metaprog_gem_init(mrb_state *);
@@ -37,13 +35,11 @@ mrb_final_mrbgems(mrb_state *mrb)
   artichoke_mrbgem_mruby_proc_ext_gem_final(mrb);
   artichoke_mrbgem_mruby_metaprog_gem_final(mrb);
   artichoke_mrbgem_mruby_eval_gem_final(mrb);
-  artichoke_mrbgem_mruby_error_gem_final(mrb);
 }
 
 void
 mrb_init_mrbgems(mrb_state *mrb)
 {
-  artichoke_mrbgem_mruby_error_gem_init(mrb);
   artichoke_mrbgem_mruby_eval_gem_init(mrb);
   artichoke_mrbgem_mruby_metaprog_gem_init(mrb);
   artichoke_mrbgem_mruby_proc_ext_gem_init(mrb);

artichoke-backend/cext/mrbgems/src/mrbgems.c

@@ -8,8 +8,6 @@ extern "C" {
 
 void mrb_mruby_class_ext_gem_init(mrb_state *mrb);
 void mrb_mruby_class_ext_gem_final(mrb_state *mrb);
-void mrb_mruby_error_gem_init(mrb_state *mrb);
-void mrb_mruby_error_gem_final(mrb_state *mrb);
 void mrb_mruby_eval_gem_init(mrb_state *mrb);
 void mrb_mruby_eval_gem_final(mrb_state *mrb);
 void mrb_mruby_fiber_gem_init(mrb_state *mrb);
@@ -41,20 +39,6 @@ artichoke_mrbgem_mruby_class_ext_gem_final(mrb_state *mrb)
   mrb_mruby_class_ext_gem_final(mrb);
 }
 
-void
-artichoke_mrbgem_mruby_error_gem_init(mrb_state *mrb)
-{
-  int ai = mrb_gc_arena_save(mrb);
-  mrb_mruby_error_gem_init(mrb);
-  mrb_gc_arena_restore(mrb, ai);
-}
-
-void
-artichoke_mrbgem_mruby_error_gem_final(mrb_state *mrb)
-{
-  mrb_mruby_error_gem_final(mrb);
-}
-
 void
 artichoke_mrbgem_mruby_eval_gem_init(mrb_state *mrb)
 {

artichoke-backend/src/convert/boxing.rs

@@ -302,7 +302,7 @@ mod tests {
     #[derive(Default, Debug, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)]
     struct Container(String);
 
-    unsafe extern "C" fn container_value(mrb: *mut sys::mrb_state, slf: sys::mrb_value) -> sys::mrb_value {
+    unsafe extern "C-unwind" fn container_value(mrb: *mut sys::mrb_state, slf: sys::mrb_value) -> sys::mrb_value {
         unwrap_interpreter!(mrb, to => guard);
 
         let mut value = Value::from(slf);

artichoke-backend/src/def.rs

@@ -17,7 +17,7 @@ use crate::Artichoke;
 
 /// Typedef for an mruby free function for an [`mrb_value`](sys::mrb_value) with
 /// `tt` [`MRB_TT_DATA`](sys::mrb_vtype::MRB_TT_DATA).
-pub type Free = unsafe extern "C" fn(mrb: *mut sys::mrb_state, data: *mut c_void);
+pub type Free = unsafe extern "C-unwind" fn(mrb: *mut sys::mrb_state, data: *mut c_void);
 
 /// A generic implementation of a [`Free`] function for [`mrb_value`]s that
 /// store an owned copy of a [`Box`] smart pointer.
@@ -38,7 +38,7 @@ pub type Free = unsafe extern "C" fn(mrb: *mut sys::mrb_state, data: *mut c_void
 ///
 /// [`mrb_value`]: sys::mrb_value
 /// [`MRB_TT_DATA`]: sys::mrb_vtype::MRB_TT_DATA
-pub unsafe extern "C" fn box_unbox_free<T>(_mrb: *mut sys::mrb_state, data: *mut c_void)
+pub unsafe extern "C-unwind" fn box_unbox_free<T>(_mrb: *mut sys::mrb_state, data: *mut c_void)
 where
     T: 'static + BoxUnboxVmValue,
 {
@@ -100,7 +100,7 @@ mod free_test {
 ///
 /// To extract method arguments, use [`mrb_get_args!`] and the supplied
 /// interpreter.
-pub type Method = unsafe extern "C" fn(mrb: *mut sys::mrb_state, slf: sys::mrb_value) -> sys::mrb_value;
+pub type Method = unsafe extern "C-unwind" fn(mrb: *mut sys::mrb_state, slf: sys::mrb_value) -> sys::mrb_value;
 
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
 pub struct ClassScope {
@@ -543,7 +543,7 @@ mod tests {
         #[derive(Debug)]
         struct Module;
 
-        extern "C" fn value(_mrb: *mut sys::mrb_state, slf: sys::mrb_value) -> sys::mrb_value {
+        extern "C-unwind" fn value(_mrb: *mut sys::mrb_state, slf: sys::mrb_value) -> sys::mrb_value {
             unsafe {
                 match slf.tt {
                     sys::mrb_vtype::MRB_TT_CLASS => sys::mrb_sys_fixnum_value(8),

artichoke-backend/src/eval.rs

@@ -102,7 +102,10 @@ mod tests {
         #[derive(Debug)]
         struct NestedEval;
 
-        unsafe extern "C" fn nested_eval_file(mrb: *mut sys::mrb_state, _slf: sys::mrb_value) -> sys::mrb_value {
+        unsafe extern "C-unwind" fn nested_eval_file(
+            mrb: *mut sys::mrb_state,
+            _slf: sys::mrb_value,
+        ) -> sys::mrb_value {
             unwrap_interpreter!(mrb, to => guard);
             let result = if let Ok(value) = guard.eval(b"__FILE__") {
                 value