From 25d3fa4d7b944b4341928a401c57feaaa0ce3c35 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Thu, 30 Sep 2021 13:09:19 -0500
Subject: [PATCH] Remove spec interpreter fuzz target temporarily (#3399)

This commit removes the `differential_spec` fuzz target for now,
although this removal is intended to be temporary. We have #3251 to
track re-enabling the spec interpreter in a way that it won't time out,
and additionally the spec interpreter is also failing to build with
ocaml on oss-fuzz so that will also need to be investigated when
re-enabling.
---
 crates/fuzzing/Cargo.toml                     |  5 +--
 .../fuzzing/wasm-spec-interpreter/src/lib.rs  |  5 +--
 fuzz/Cargo.toml                               |  6 ----
 fuzz/fuzz_targets/differential_spec.rs        | 31 -------------------
 4 files changed, 6 insertions(+), 41 deletions(-)
 delete mode 100644 fuzz/fuzz_targets/differential_spec.rs

diff --git a/crates/fuzzing/Cargo.toml b/crates/fuzzing/Cargo.toml
index 4e6a0ca746..fcdcfac483 100644
--- a/crates/fuzzing/Cargo.toml
+++ b/crates/fuzzing/Cargo.toml
@@ -32,7 +32,8 @@ rusty_v8 = "0.27"
 [dev-dependencies]
 wat = "1.0.37"
 
+# FIXME(#3251) should re-enable once spec interpreter won't time out
 # We only build the library containing the OCaml spec interpreter if the OCaml
 # toolchain is available--which is assumed here to be the case when fuzzing.
-[target.'cfg(fuzzing)'.dependencies]
-wasm-spec-interpreter = { path = "./wasm-spec-interpreter", features = ["build-libinterpret"] }
+# [target.'cfg(fuzzing)'.dependencies]
+# wasm-spec-interpreter = { path = "./wasm-spec-interpreter", features = ["build-libinterpret"] }
diff --git a/crates/fuzzing/wasm-spec-interpreter/src/lib.rs b/crates/fuzzing/wasm-spec-interpreter/src/lib.rs
index a2f46a3a9a..20440c500e 100644
--- a/crates/fuzzing/wasm-spec-interpreter/src/lib.rs
+++ b/crates/fuzzing/wasm-spec-interpreter/src/lib.rs
@@ -28,6 +28,7 @@ mod without_library;
 #[cfg(not(feature = "has-libinterpret"))]
 pub use without_library::*;
 
+// FIXME(#3251) should re-enable once spec interpreter won't time out
 // If the user is fuzzing`, we expect the OCaml library to have been built.
-#[cfg(all(fuzzing, not(feature = "has-libinterpret")))]
-compile_error!("The OCaml library was not built.");
+// #[cfg(all(fuzzing, not(feature = "has-libinterpret")))]
+// compile_error!("The OCaml library was not built.");
diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
index 9f30a38326..b673450ba3 100644
--- a/fuzz/Cargo.toml
+++ b/fuzz/Cargo.toml
@@ -52,12 +52,6 @@ path = "fuzz_targets/differential.rs"
 test = false
 doc = false
 
-[[bin]]
-name = "differential_spec"
-path = "fuzz_targets/differential_spec.rs"
-test = false
-doc = false
-
 [[bin]]
 name = "differential_wasmi"
 path = "fuzz_targets/differential_wasmi.rs"
diff --git a/fuzz/fuzz_targets/differential_spec.rs b/fuzz/fuzz_targets/differential_spec.rs
deleted file mode 100644
index 3116d24a0a..0000000000
--- a/fuzz/fuzz_targets/differential_spec.rs
+++ /dev/null
@@ -1,31 +0,0 @@
-#![no_main]
-
-use libfuzzer_sys::fuzz_target;
-use std::sync::atomic::{AtomicUsize, Ordering::SeqCst};
-use wasmtime_fuzzing::{generators, oracles};
-
-// Keep track of how many WebAssembly modules we actually executed (i.e. ran to
-// completion) versus how many were tried.
-static TRIED: AtomicUsize = AtomicUsize::new(0);
-static EXECUTED: AtomicUsize = AtomicUsize::new(0);
-
-fuzz_target!(|data: (
-    generators::Config,
-    wasm_smith::ConfiguredModule<oracles::SingleFunctionModuleConfig<false, false>>
-)| {
-    let (config, mut wasm) = data;
-    wasm.module.ensure_termination(1000);
-    let tried = TRIED.fetch_add(1, SeqCst);
-    let executed = match oracles::differential_spec_execution(&wasm.module.to_bytes(), &config) {
-        Some(_) => EXECUTED.fetch_add(1, SeqCst),
-        None => EXECUTED.load(SeqCst),
-    };
-    if tried > 0 && tried % 1000 == 0 {
-        println!(
-            "=== Execution rate ({} executed modules / {} tried modules): {}% ===",
-            executed,
-            tried,
-            executed as f64 / tried as f64 * 100f64
-        )
-    }
-});