From 05b149b275676df1a49d11f1d2d41335aeb2f3f4 Mon Sep 17 00:00:00 2001
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 <t2026104239910027@eduxiji.net>
Date: Tue, 30 Jun 2026 16:01:00 +0800
Subject: [PATCH] =?UTF-8?q?fix:=20=E9=A1=B6=E5=B1=82=20count=20pass=20?=
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---
 crates/oxide_compiler/src/compiler.rs         | 13 +++++++++++-
 .../tests/compiler_alignment_expr_tests.rs    | 20 +++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/crates/oxide_compiler/src/compiler.rs b/crates/oxide_compiler/src/compiler.rs
index 5bd699c..e999f65 100644
--- a/crates/oxide_compiler/src/compiler.rs
+++ b/crates/oxide_compiler/src/compiler.rs
@@ -866,8 +866,19 @@ impl Compiler {
         let mut ctx = CompileCtx::new();
         ctx.pre_register_builtins();
 
+        // The emit pass below hoists FunctionDeclarations to the front. The count pass
+        // must walk in that same order: counting in source order would record jump-target
+        // labels at source-order PCs while emit places code at hoisted-order PCs, drifting
+        // every jump that sits after a hoisted function declaration (infinite loops at run).
         for stmt in &program.body {
-            self.count_statement(stmt, &mut ctx);
+            if matches!(stmt, Statement::FunctionDeclaration(_)) {
+                self.count_statement(stmt, &mut ctx);
+            }
+        }
+        for stmt in &program.body {
+            if !matches!(stmt, Statement::FunctionDeclaration(_)) {
+                self.count_statement(stmt, &mut ctx);
+            }
         }
         crate::compiler_debug!("counter: {} instructions estimated", ctx.projected_pc);
         ctx.max_regs = ctx.max_regs.max(1);
diff --git a/crates/oxide_vm/tests/compiler_alignment_expr_tests.rs b/crates/oxide_vm/tests/compiler_alignment_expr_tests.rs
index 5d8a3e8..050eeb6 100644
--- a/crates/oxide_vm/tests/compiler_alignment_expr_tests.rs
+++ b/crates/oxide_vm/tests/compiler_alignment_expr_tests.rs
@@ -38,6 +38,26 @@ fn coalesce_nonsimple_then_while() {
     );
 }
 
+// A jump-bearing construct (if/loop) followed by a hoisted function declaration:
+// the count pass must walk in the same function-hoisting order as the emit pass,
+// otherwise the construct's jump targets drift past the hoisted body and the
+// program loops forever at run time.
+
+#[test]
+fn if_then_hoisted_function() {
+    assert_eq!(eval("if(false){} function f(){return 1} f()"), "1");
+}
+
+#[test]
+fn for_of_then_hoisted_function() {
+    assert_eq!(eval("var r=0; for(const x of [1,2,3]) r+=x; function f(){return 100} r + f()"), "106");
+}
+
+#[test]
+fn while_then_hoisted_function() {
+    assert_eq!(eval("var n=0; while(n<3){n=n+1;} function f(){return 100} n + f()"), "103");
+}
+
 #[test]
 fn coalesce_nonsimple_then_for() {
     assert_eq!(