From 64ea964bc0b6f985de4064393f5652cee8fdb812 Mon Sep 17 00:00:00 2001
From: Dan Gohman <sunfish@mozilla.com>
Date: Tue, 18 Dec 2018 14:13:46 -0800
Subject: [PATCH] Change the `elems` parameter of `declare_table_elements` to a
 boxed slice.

Implementations that want a full `Vec` can use `into_vec` to convert it
back.
---
 lib/wasm/src/environ/dummy.rs       | 2 +-
 lib/wasm/src/environ/spec.rs        | 4 ++--
 lib/wasm/src/sections_translator.rs | 7 ++++++-
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/lib/wasm/src/environ/dummy.rs b/lib/wasm/src/environ/dummy.rs
index 290aa38c0..5bf196168 100644
--- a/lib/wasm/src/environ/dummy.rs
+++ b/lib/wasm/src/environ/dummy.rs
@@ -402,7 +402,7 @@ impl<'data> ModuleEnvironment<'data> for DummyEnvironment {
         _table_index: TableIndex,
         _base: Option<GlobalIndex>,
         _offset: usize,
-        _elements: Vec<FuncIndex>,
+        _elements: Box<[FuncIndex]>,
     ) {
         // We do nothing
     }
diff --git a/lib/wasm/src/environ/spec.rs b/lib/wasm/src/environ/spec.rs
index 37d741a4f..92c7fa9e2 100644
--- a/lib/wasm/src/environ/spec.rs
+++ b/lib/wasm/src/environ/spec.rs
@@ -14,8 +14,8 @@ use cranelift_codegen::ir::immediates::Offset32;
 use cranelift_codegen::ir::{self, InstBuilder};
 use cranelift_codegen::isa::TargetFrontendConfig;
 use failure_derive::Fail;
+use std::boxed::Box;
 use std::convert::From;
-use std::vec::Vec;
 use wasmparser::BinaryReaderError;
 
 /// The value of a WebAssembly global variable.
@@ -336,7 +336,7 @@ pub trait ModuleEnvironment<'data> {
         table_index: TableIndex,
         base: Option<GlobalIndex>,
         offset: usize,
-        elements: Vec<FuncIndex>,
+        elements: Box<[FuncIndex]>,
     );
 
     /// Provides the contents of a function body.
diff --git a/lib/wasm/src/sections_translator.rs b/lib/wasm/src/sections_translator.rs
index 89c1750c8..6192ec7b0 100644
--- a/lib/wasm/src/sections_translator.rs
+++ b/lib/wasm/src/sections_translator.rs
@@ -253,7 +253,12 @@ pub fn parse_element_section<'data>(
             let x = item?;
             elems.push(FuncIndex::from_u32(x));
         }
-        environ.declare_table_elements(TableIndex::from_u32(table_index), base, offset, elems)
+        environ.declare_table_elements(
+            TableIndex::from_u32(table_index),
+            base,
+            offset,
+            elems.into_boxed_slice(),
+        )
     }
     Ok(())
 }