No public description

PiperOrigin-RevId: 1003288911

rust/cargo_fuzztest/src/lib.rs

diff --git a/rust/cargo_fuzztest/src/lib.rs b/rust/cargo_fuzztest/src/lib.rs
index fe9afcd..a0d55e7 100644
--- a/rust/cargo_fuzztest/src/lib.rs
+++ b/rust/cargo_fuzztest/src/lib.rs
@@ -323,6 +323,10 @@
             cmd.arg("--nocapture");
         }
 
+        if self.options.fuzztest_options.unguided {
+            cmd.env("FUZZTEST_UNGUIDED", "true");
+        }
+
         Ok(cmd)
     }
 

rust/options/src/lib.rs

diff --git a/rust/options/src/lib.rs b/rust/options/src/lib.rs
index d84bb4a..94cb383 100644
--- a/rust/options/src/lib.rs
+++ b/rust/options/src/lib.rs
@@ -142,6 +142,10 @@
     /// sessions, or skipping tests that already finished with the same execution ID.
     #[arg(env = "FUZZTEST_EXECUTION_ID", long, requires = "corpus_db")]
     pub execution_id: Option<String>,
+
+    /// If true, carries out fuzzing without coverage guidance.
+    #[arg(env = "FUZZTEST_UNGUIDED", long)]
+    pub unguided: bool,
 }
 
 /// Strongly-typed domain execution mode for test runs.
@@ -819,4 +823,17 @@
             }))
         );
     }
+
+    #[gtest]
+    fn test_unguided_parsing_env() {
+        assert_single_threaded_test_environment();
+        // SAFETY: Single-threaded test environment and no background threads.
+        let options = unsafe {
+            with_env_var("FUZZTEST_UNGUIDED", "true", || {
+                FuzzTestOptions::parse_from(std::iter::empty::<OsString>())
+            })
+        };
+
+        expect_true!(options.unguided);
+    }
 }

rust/src/worker.rs

diff --git a/rust/src/worker.rs b/rust/src/worker.rs
index cd9ed80..fcfbd6a 100644
--- a/rust/src/worker.rs
+++ b/rust/src/worker.rs
@@ -196,6 +196,8 @@
     pub fn execute(&self, input: &GenericCorpusValue, sink: &mut FeedbackSink) {
         // TODO(the-shank): modify this in order to support persistent mode and batch execution.
         static CLEAR_STARTUP_COVERAGE: AtomicBool = AtomicBool::new(true);
+        // Called even in unguided mode: besides clearing coverage, this frees the SanCov state of
+        // threads that exited during the previous execution, which would otherwise accumulate.
         coverage::prepare_coverage(CLEAR_STARTUP_COVERAGE.swap(false, Ordering::AcqRel));
 
         // SAFETY: We are currently in the `execute` callback of `RustFuzzTestAdapter`.
@@ -203,9 +205,10 @@
 
         let result = self.fuzz_test.execute(input);
 
-        coverage::post_process_coverage(false);
-
-        sink.emit_sancov_features();
+        if !options::get_fuzztest_options().unguided {
+            coverage::post_process_coverage(false);
+            sink.emit_sancov_features();
+        }
 
         if !result {
             // TODO(the-shank): the signature should be different for different panics. Currently,