add printouts for debugging

Author: Jamesbarford

crates/intrinsic-test/src/main.rs

@@ -624,14 +624,27 @@ fn compare_outputs(
             };
 
             if !c.status.success() {
-                error!("Failed to run C program for intrinsic {}", intrinsic.name);
+                error!(
+                    "Failed to run C program for intrinsic {intrinsic} - {error}",
+                    intrinsic = intrinsic.name,
+                    error = String::from_utf8(c.stderr).unwrap_or(
+                        String::from_utf8(c.stdout).unwrap_or(
+                            "C program produced no output to `stderr` or `stdout`".to_string()
+                        )
+                    )
+                );
                 return Some(FailureReason::RunC(intrinsic.name.clone()));
             }
 
             if !rust.status.success() {
                 error!(
-                    "Failed to run rust program for intrinsic {}",
-                    intrinsic.name
+                    "Failed to run Rust program for intrinsic {intrinsic} - {error}",
+                    intrinsic = intrinsic.name,
+                    error = String::from_utf8(rust.stderr).unwrap_or(
+                        String::from_utf8(rust.stdout).unwrap_or(
+                            "Rust program produced no output to `stderr` or `stdout`".to_string()
+                        )
+                    )
                 );
                 return Some(FailureReason::RunRust(intrinsic.name.clone()));
             }