From e89511b14cdfd5694e90bf704a6853c67e8dde68 Mon Sep 17 00:00:00 2001
From: Jakub Doka <jakub.doka2@gmail.com>
Date: Sun, 17 Nov 2024 22:26:31 +0100
Subject: [PATCH] fixing position reporting for optimized returns

---
 lang/src/son.rs | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/lang/src/son.rs b/lang/src/son.rs
index 708554a4..fe102504 100644
--- a/lang/src/son.rs
+++ b/lang/src/son.rs
@@ -24,7 +24,6 @@ use {
         fmt::{self, Debug, Display, Write},
         format_args as fa, mem,
         ops::{self, Range},
-        usize,
     },
     hashbrown::hash_map,
     hbbytecode::DisasmError,
@@ -1066,7 +1065,9 @@ impl Nodes {
                 }
 
                 if new_inps.as_slice() != self[target].inputs.as_slice() {
-                    return Some(self.new_node_nop(ty::Id::VOID, Kind::Return { file }, new_inps));
+                    let ret = self.new_node_nop(ty::Id::VOID, Kind::Return { file }, new_inps);
+                    self[ret].pos = self[target].pos;
+                    return Some(ret);
                 }
             }
             K::Phi => {
@@ -2793,11 +2794,6 @@ impl<'a> Codegen<'a> {
                         }
                     }
 
-                    debug_assert_eq!(
-                        lexer::Lexer::new(&self.file().file[pos as usize..]).eat().kind,
-                        TokenKind::Return
-                    );
-
                     let ret = self.ci.nodes.new_node_nop(
                         ty::Id::VOID,
                         Kind::Return { file: self.ci.file },
@@ -4712,17 +4708,18 @@ impl<'a> Codegen<'a> {
 
         for &node in self.ci.nodes[NEVER].inputs.iter() {
             if let Kind::Return { file } = self.ci.nodes[node].kind
-                && self.ci.nodes[self.ci.nodes.aclass_index(self.ci.nodes[node].inputs[1]).1].kind
-                    == Kind::Stck
+                && let (_, stck) = self.ci.nodes.aclass_index(self.ci.nodes[node].inputs[1])
+                && self.ci.nodes[stck].kind == Kind::Stck
             {
                 let pfile = mem::replace(&mut self.ci.file, file);
+                debug_assert!(self.ci.nodes[node].pos != 0);
                 self.error(
                     self.ci.nodes[node].pos,
                     "returning value with local provenance \
                     (pointer will be invalid after function returns)",
                 );
                 self.error(
-                    self.ci.nodes[self.ci.nodes.aclass_index(self.ci.nodes[node].inputs[1]).1].pos,
+                    self.ci.nodes[stck].pos,
                     "...the pointer points to stack allocation created here",
                 );
                 self.ci.file = pfile;