run tests in thread with bigger stack

zokrates_cli/src/bin.rs

@@ -72,6 +72,10 @@ mod tests {
 
     #[test]
     fn compile_examples() {
+        let builder = std::thread::Builder::new().stack_size(8388608);
+
+        builder
+            .spawn(|| {
                 for p in glob("./examples/**/*").expect("Failed to read glob pattern") {
                     let path = match p {
                         Ok(x) => x,
@@ -101,6 +105,8 @@ mod tests {
 
                     assert_eq!(res.is_err(), should_error);
                 }
+            })
+            .unwrap();
     }
 
     #[test]

zokrates_field/src/lib.rs

@@ -60,6 +60,7 @@ pub trait Field:
     + Ord
     + Display
     + Debug
+    + Send
     + Add<Self, Output = Self>
     + for<'a> Add<&'a Self, Output = Self>
     + Sub<Self, Output = Self>
@@ -151,6 +152,8 @@ mod prime_field {
                 value: BigInt,
             }
 
+            unsafe impl Send for FieldPrime {}
+
             impl Field for FieldPrime {
                 fn bits(&self) -> u32 {
                     self.value.bits() as u32

zokrates_test/src/lib.rs

@@ -95,6 +95,12 @@ pub fn test_inner(test_path: &str) {
 
     let curves = t.curves.clone().unwrap_or(vec![Curve::Bn128]);
 
+    // this function typically runs in a spawn thread whose stack size is small, leading to stack overflows
+    // to avoid that, run the stack-heavy bit in a thread with a larger stack (8M)
+    let builder = std::thread::Builder::new().stack_size(8388608);
+
+    builder
+        .spawn(move || {
             for c in &curves {
                 match c {
                     Curve::Bn128 => compile_and_run::<Bn128Field>(t.clone()),
@@ -103,6 +109,10 @@ pub fn test_inner(test_path: &str) {
                     Curve::Bw6_761 => compile_and_run::<Bw6_761Field>(t.clone()),
                 }
             }
+        })
+        .unwrap()
+        .join()
+        .unwrap();
 }
 
 fn compile_and_run<T: Field>(t: Tests) {