Remove the explicit gc feature from the wasmtime dependency in the c-api crate (bytecodealliance#12805)

* Remove the explicit gc feature from the wasmtime dependency in the c-api crate

* Fixes thrownexcpetion import which is behind gc

* Adds more wasmtime_feature_gc gate, and moves some definition outside the gate

Author: tolumide-ng

.github/workflows/main.yml

@@ -414,6 +414,7 @@ jobs:
               -p wasmtime-c-api --no-default-features
               -p wasmtime-c-api --no-default-features --features wat
               -p wasmtime-c-api --no-default-features --features wasi
+              -p wasmtime-c-api --no-default-features --features gc
 
           - name: wasmtime-wasi-http
             checks: |

crates/c-api-macros/src/lib.rs

@@ -135,13 +135,15 @@ pub fn declare_ref(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
 
         #[doc = #as_ref_docs]
         #[unsafe(no_mangle)]
+        #[cfg(feature = "gc")]
         pub extern fn #as_ref(a: &#ty) -> Box<crate::wasm_ref_t> {
             eprintln!("`{}` is not implemented", stringify!(#as_ref));
             std::process::abort();
         }
 
         #[doc = #as_ref_const_docs]
         #[unsafe(no_mangle)]
+        #[cfg(feature = "gc")]
         pub extern fn #as_ref_const(a: &#ty) -> Box<crate::wasm_ref_t> {
             eprintln!("`{}` is not implemented", stringify!(#as_ref_const));
             std::process::abort();

crates/c-api/Cargo.toml

@@ -21,7 +21,7 @@ doctest = false
 
 [dependencies]
 env_logger = { workspace = true, optional = true }
-wasmtime = { workspace = true, features = ['runtime', 'gc', 'std'] }
+wasmtime = { workspace = true, features = ['runtime', 'std'] }
 wasmtime-c-api-macros = { workspace = true }
 log = { workspace = true }
 tracing = { workspace = true }

crates/c-api/include/wasmtime/config.hh

@@ -303,13 +303,15 @@ class Config {
     wasmtime_config_wasm_tail_call_set(ptr.get(), enable);
   }
 
+#ifdef WASMTIME_FEATURE_GC
   /// \brief Configures whether the WebAssembly reference types proposal is
   /// enabled
   ///
   /// https://docs.wasmtime.dev/api/wasmtime/struct.Config.html#method.wasm_reference_types
   void wasm_reference_types(bool enable) {
     wasmtime_config_wasm_reference_types_set(ptr.get(), enable);
   }
+#endif // WASMTIME_FEATURE_GC
 
   /// \brief Configures whether the WebAssembly simd proposal is enabled
   ///
@@ -361,11 +363,13 @@ class Config {
     wasmtime_config_wasm_memory64_set(ptr.get(), enable);
   }
 
+#ifdef WASMTIME_FEATURE_GC
   /// \brief Configures whether the WebAssembly Garbage Collection proposal will
   /// be enabled
   ///
   /// https://docs.wasmtime.dev/api/wasmtime/struct.Config.html#method.wasm_gc
   void wasm_gc(bool enable) { wasmtime_config_wasm_gc_set(ptr.get(), enable); }
+#endif // WASMTIME_FEATURE_GC
 
   /// \brief Configures whether the WebAssembly function references proposal
   /// will be enabled
@@ -383,13 +387,15 @@ class Config {
     wasmtime_config_wasm_wide_arithmetic_set(ptr.get(), enable);
   }
 
+#ifdef WASMTIME_FEATURE_GC
   /// \brief Configures whether the WebAssembly exceptions proposal will be
   /// enabled
   ///
   /// https://docs.wasmtime.dev/api/wasmtime/struct.Config.html#method.wasm_exceptions
   void wasm_exceptions(bool enable) {
     wasmtime_config_wasm_exceptions_set(ptr.get(), enable);
   }
+#endif // WASMTIME_FEATURE_GC
 
   /// \brief Configures whether the WebAssembly custom-page-sizes proposal will
   /// be enabled

crates/c-api/include/wasmtime/func.hh

@@ -81,6 +81,7 @@ NATIVE_WASM_TYPE(double, F64, f64)
 
 #undef NATIVE_WASM_TYPE
 
+#ifdef WASMTIME_FEATURE_GC
 /// Type information for `externref`, represented on the host as an optional
 /// `ExternRef`.
 template <> struct WasmType<std::optional<ExternRef>> {
@@ -102,6 +103,7 @@ template <> struct WasmType<std::optional<ExternRef>> {
       p->externref = 0;
     }
   }
+
   static std::optional<ExternRef> load(Store::Context cx,
                                        wasmtime_val_raw_t *p) {
     if (p->externref == 0) {
@@ -112,6 +114,7 @@ template <> struct WasmType<std::optional<ExternRef>> {
     return ExternRef(val);
   }
 };
+#endif // WASMTIME_FEATURE_GC
 
 /// Type information for the `V128` host value used as a wasm value.
 template <> struct WasmType<V128> {

crates/c-api/include/wasmtime/gc.h

@@ -11,6 +11,8 @@
 #ifndef WASMTIME_GC_H
 #define WASMTIME_GC_H
 
+#ifdef WASMTIME_FEATURE_GC
+
 #include <wasmtime/val.h>
 
 #ifdef __cplusplus
@@ -593,4 +595,5 @@ WASM_API_EXTERN bool wasmtime_anyref_as_array(wasmtime_context_t *context,
 } // extern "C"
 #endif
 
+#endif // WASMTIME_FEATURE_GC
 #endif // WASMTIME_GC_H

crates/c-api/include/wasmtime/gc.hh

@@ -7,6 +7,9 @@
 #ifndef WASMTIME_GC_HH
 #define WASMTIME_GC_HH
 
+#include <wasmtime/config.hh>
+
+#ifdef WASMTIME_FEATURE_GC
 #include <vector>
 #include <wasmtime/gc.h>
 #include <wasmtime/val.hh>
@@ -476,4 +479,6 @@ inline std::optional<ArrayRef> AnyRef::as_array(Store::Context cx) const {
 
 } // namespace wasmtime
 
+#endif // WASMTIME_FEATURE_GC
+
 #endif // WASMTIME_GC_HH

crates/c-api/include/wasmtime/store.h

@@ -144,8 +144,10 @@ WASM_API_EXTERN void wasmtime_context_set_data(wasmtime_context_t *context,
  *
  * The `context` argument must not be NULL.
  */
+#ifdef WASMTIME_FEATURE_GC
 WASM_API_EXTERN wasmtime_error_t *
 wasmtime_context_gc(wasmtime_context_t *context);
+#endif
 
 /**
  * \brief Set fuel to this context's store for wasm to consume while executing.

crates/c-api/include/wasmtime/store.hh

@@ -94,6 +94,7 @@ public:
     /// Creates a context referencing the provided `Caller`.
     Context(Caller *caller);
 
+#ifdef WASMTIME_FEATURE_GC
     /// Runs a garbage collection pass in the referenced store to collect loose
     /// `externref` values, if any are available.
     Result<std::monostate> gc() {
@@ -103,6 +104,7 @@ public:
       }
       return std::monostate();
     }
+#endif
 
     /// Injects fuel to be consumed within this store.
     ///
@@ -253,9 +255,11 @@ public:
   /// Explicit function to acquire a `Context` from this store.
   Context context() { return this; }
 
+#ifdef WASMTIME_FEATURE_GC
   /// Runs a garbage collection pass in the referenced store to collect loose
   /// GC-managed objects, if any are available.
   Result<std::monostate> gc() { return context().gc(); }
+#endif
 
 private:
   template <typename F>

crates/c-api/include/wasmtime/val.h

@@ -15,6 +15,7 @@
 extern "C" {
 #endif
 
+#ifdef WASMTIME_FEATURE_GC
 struct wasmtime_eqref;
 /// Convenience alias for #wasmtime_eqref
 typedef struct wasmtime_eqref wasmtime_eqref_t;
@@ -201,6 +202,7 @@ WASM_API_EXTERN bool wasmtime_anyref_i31_get_s(wasmtime_context_t *context,
  * `wasmtime_externref_set_null`. Null can be tested for with the
  * `wasmtime_externref_is_null` function.
  */
+
 typedef struct wasmtime_externref {
   /// Internal metadata tracking within the store, embedders should not
   /// configure or modify these fields.
@@ -367,6 +369,7 @@ WASM_API_EXTERN void wasmtime_exnref_clone(const wasmtime_exnref_t *ref,
  * After this call, `ref` is left in an undefined state and should not be used.
  */
 WASM_API_EXTERN void wasmtime_exnref_unroot(wasmtime_exnref_t *ref);
+#endif // WASMTIME_FEATURE_GC
 
 /// \brief Discriminant stored in #wasmtime_val::kind
 typedef uint8_t wasmtime_valkind_t;
@@ -416,6 +419,7 @@ typedef union wasmtime_valunion {
   float32_t f32;
   /// Field used if #wasmtime_val_t::kind is #WASMTIME_F64
   float64_t f64;
+#ifdef WASMTIME_FEATURE_GC
   /// Field used if #wasmtime_val_t::kind is #WASMTIME_ANYREF
   wasmtime_anyref_t anyref;
   /// Field used if #wasmtime_val_t::kind is #WASMTIME_EXTERNREF
@@ -427,6 +431,7 @@ typedef union wasmtime_valunion {
   /// Use `wasmtime_funcref_is_null` to test whether this is a null function
   /// reference.
   wasmtime_func_t funcref;
+#endif // WASMTIME_FEATURE_GC
   /// Field used if #wasmtime_val_t::kind is #WASMTIME_V128
   wasmtime_v128 v128;
 } wasmtime_valunion_t;