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crates/runtime/src/lib.rs

@@ -69,45 +69,13 @@ pub use module_id::{CompiledModuleId, CompiledModuleIdAllocator};
 
 #[cfg(feature = "memfd-allocator")]
 mod memfd;
+#[cfg(feature = "memfd-allocator")]
+pub use crate::memfd::{MemFdSlot, MemoryMemFd, ModuleMemFds};
 
-pub use crate::memfd::MemoryMemFd;
-
-/// When memfd support is not included, provide a shim type and
-/// constructor instead so that higher-level code does not need
-/// feature-conditional compilation.
 #[cfg(not(feature = "memfd-allocator"))]
-#[allow(dead_code)]
-mod memfd {
-    use anyhow::Result;
-    use std::sync::Arc;
-    use wasmtime_environ::{DefinedMemoryIndex, Module};
-
-    /// A shim for the memfd image container when memfd support is not
-    /// included.
-    pub enum ModuleMemFds {}
-
-    /// A shim for an individual memory image.
-    #[allow(dead_code)]
-    pub enum MemoryMemFd {}
-
-    impl ModuleMemFds {
-        /// Construct a new set of memfd images. This variant is used
-        /// when memfd support is not included; it always returns no
-        /// images.
-        pub fn new(_: &Module, _: &[u8]) -> Result<Option<Arc<ModuleMemFds>>> {
-            Ok(None)
-        }
-
-        /// Get the memfd image for a particular memory.
-        pub(crate) fn get_memory_image(&self, _: DefinedMemoryIndex) -> Option<&Arc<MemoryMemFd>> {
-            // Should be unreachable because the `Self` type is
-            // uninhabitable.
-            match *self {}
-        }
-    }
-}
-
-pub use crate::memfd::ModuleMemFds;
+mod memfd_disabled;
+#[cfg(not(feature = "memfd-allocator"))]
+pub use crate::memfd_disabled::{MemFdSlot, MemoryMemFd, ModuleMemFds};
 
 /// Version number of this crate.
 pub const VERSION: &str = env!("CARGO_PKG_VERSION");