From 2a775d822e8d1116ff260a57c0ea6efa1ea873ad Mon Sep 17 00:00:00 2001
From: David Mak <csdavidmak@ust.hk>
Date: Fri, 29 Sep 2023 17:49:09 +0800
Subject: [PATCH] core: Demote dead code into a stdout warning

---
 nac3core/src/codegen/mod.rs                   | 8 +++-----
 nac3core/src/typecheck/function_check.rs      | 2 +-
 nac3standalone/demo/src/dead_code_issue118.py | 8 ++++++++
 3 files changed, 12 insertions(+), 6 deletions(-)
 create mode 100644 nac3standalone/demo/src/dead_code_issue118.py

diff --git a/nac3core/src/codegen/mod.rs b/nac3core/src/codegen/mod.rs
index 8d2e39f2..9006a59c 100644
--- a/nac3core/src/codegen/mod.rs
+++ b/nac3core/src/codegen/mod.rs
@@ -1,4 +1,5 @@
 use crate::{
+    codegen::stmt::gen_block,
     symbol_resolver::{StaticValue, SymbolResolver},
     toplevel::{TopLevelContext, TopLevelDef},
     typecheck::{
@@ -160,7 +161,7 @@ pub struct CodeGenContext<'ctx, 'a> {
 
 impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
     pub fn is_terminated(&self) -> bool {
-        self.builder.get_insert_block().unwrap().get_terminator().is_some()
+        self.builder.get_insert_block().and_then(|bb| bb.get_terminator()).is_some()
     }
 }
 
@@ -854,10 +855,7 @@ pub fn gen_func<'ctx, G: CodeGenerator>(
 ) -> Result<(Builder<'ctx>, Module<'ctx>, FunctionValue<'ctx>), (Builder<'ctx>, String)> {
     let body = task.body.clone();
     gen_func_impl(context, generator, registry, builder, module, task, |generator, ctx| {
-        for stmt in body.iter() {
-            generator.gen_stmt(ctx, stmt)?;
-        }
-        Ok(())
+        gen_block(generator, ctx, body.iter())
     })
 }
 
diff --git a/nac3core/src/typecheck/function_check.rs b/nac3core/src/typecheck/function_check.rs
index c2dc884d..2c4b28b3 100644
--- a/nac3core/src/typecheck/function_check.rs
+++ b/nac3core/src/typecheck/function_check.rs
@@ -295,7 +295,7 @@ impl<'a> Inferencer<'a> {
         let mut ret = false;
         for stmt in block {
             if ret {
-                return Err(format!("dead code at {:?}", stmt.location));
+                println!("warning: dead code at {:?}\n", stmt.location)
             }
             if self.check_stmt(stmt, defined_identifiers)? {
                 ret = true;
diff --git a/nac3standalone/demo/src/dead_code_issue118.py b/nac3standalone/demo/src/dead_code_issue118.py
new file mode 100644
index 00000000..c1f62225
--- /dev/null
+++ b/nac3standalone/demo/src/dead_code_issue118.py
@@ -0,0 +1,8 @@
+def f():
+	return
+	return
+
+def run() -> int32:
+	f()
+
+	return 0
\ No newline at end of file