Fix syscall featurization (#12714)

* Fix syscall featurization

* nudge

programs/bpf/rust/ristretto/src/lib.rs

@@ -2,21 +2,13 @@
 
 pub mod ristretto;
 
-extern crate solana_sdk;
 use crate::ristretto::ristretto_mul;
 use curve25519_dalek::{constants::RISTRETTO_BASEPOINT_POINT, scalar::Scalar};
 use solana_sdk::{
     account_info::AccountInfo, entrypoint, entrypoint::ProgramResult, info, pubkey::Pubkey,
 };
 
-entrypoint!(process_instruction);
-fn process_instruction(
-    _program_id: &Pubkey,
-    _accounts: &[AccountInfo],
-    _instruction_data: &[u8],
-) -> ProgramResult {
-    info!("Ristretto multiply");
-
+fn test_ristretto_mul() -> ProgramResult {
     let point = RISTRETTO_BASEPOINT_POINT;
     let scalar = Scalar::zero();
     let result = ristretto_mul(&point, &scalar)?;
@@ -29,3 +21,28 @@ fn process_instruction(
 
     Ok(())
 }
+
+entrypoint!(process_instruction);
+fn process_instruction(
+    _program_id: &Pubkey,
+    _accounts: &[AccountInfo],
+    _instruction_data: &[u8],
+) -> ProgramResult {
+    info!("Ristretto multiply");
+
+    test_ristretto_mul()?;
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    // Pull in syscall stubs when building for non-BPF targets
+    solana_sdk::program_stubs!();
+
+    #[test]
+    fn test_ristretto() {
+        test_ristretto_mul().unwrap();
+    }
+}