diff --git a/crates/cyrusc_codegen_llvm/src/builder/builder.rs b/crates/cyrusc_codegen_llvm/src/builder/builder.rs
index 8378583a3..607ec8916 100644
--- a/crates/cyrusc_codegen_llvm/src/builder/builder.rs
+++ b/crates/cyrusc_codegen_llvm/src/builder/builder.rs
@@ -24,6 +24,10 @@ use cyrusc_typed_ast::LabelID;
 use inkwell::{
     basic_block::BasicBlock, builder::Builder, context::Context, module::Module, targets::TargetMachine,
     values::FunctionValue,
+    llvm_sys::{
+        core::{LLVMGetCurrentDebugLocation2, LLVMSetCurrentDebugLocation2},
+        prelude::{LLVMBuilderRef, LLVMMetadataRef},
+    },
 };
 use std::{cell::RefCell, collections::HashMap, rc::Rc, sync::Arc};
 
@@ -238,3 +242,43 @@ impl<'ll> Default for BlockRegistry<'ll> {
         }
     }
 }
+
+pub struct DebugLocationGuard {
+    builder: LLVMBuilderRef,
+    saved_loc: Option<LLVMMetadataRef>,
+}
+
+impl DebugLocationGuard {
+    pub fn new(builder_ref: LLVMBuilderRef, dctx_exists: bool) -> Self {
+        let saved_loc = if dctx_exists {
+            unsafe {
+                let loc = LLVMGetCurrentDebugLocation2(builder_ref);
+                if !loc.is_null() {
+                    Some(loc)
+                } else {
+                    None
+                }
+            }
+        } else {
+            None
+        };
+
+        if saved_loc.is_some() {
+            unsafe {
+                LLVMSetCurrentDebugLocation2(builder_ref, std::ptr::null_mut());
+            }
+        }
+
+        Self { builder: builder_ref, saved_loc }
+    }
+}
+
+impl Drop for DebugLocationGuard {
+    fn drop(&mut self) {
+        if let Some(loc) = self.saved_loc {
+            unsafe {
+                LLVMSetCurrentDebugLocation2(self.builder, loc);
+            }
+        }
+    }
+}
diff --git a/crates/cyrusc_codegen_llvm/src/builder/control_flow.rs b/crates/cyrusc_codegen_llvm/src/builder/control_flow.rs
index 630d1a017..532b6cf4d 100644
--- a/crates/cyrusc_codegen_llvm/src/builder/control_flow.rs
+++ b/crates/cyrusc_codegen_llvm/src/builder/control_flow.rs
@@ -1078,8 +1078,11 @@ impl<'ll> CodeGenIRBuilder<'ll> {
                 return;
             }
 
+            if self.blockreg.cur_block.unwrap().get_terminator().is_none() {
+                LLVMBuildBr(self.llvmbuilder.as_mut_ptr(), next_block);
+            }
+
             self.blockreg.cur_block = None;
-            LLVMBuildBr(self.llvmbuilder.as_mut_ptr(), next_block);
         }
     }
 
@@ -1088,8 +1091,12 @@ impl<'ll> CodeGenIRBuilder<'ll> {
             if !self.llvm_emit_check_block_branch() {
                 return;
             }
+
+            if self.blockreg.cur_block.unwrap().get_terminator().is_none() {
+                LLVMBuildCondBr(self.llvmbuilder.as_mut_ptr(), cond, then_block, else_block);
+            }
+
             self.blockreg.cur_block = None;
-            LLVMBuildCondBr(self.llvmbuilder.as_mut_ptr(), cond, then_block, else_block);
         }
     }
 
diff --git a/crates/cyrusc_codegen_llvm/src/builder/exprs.rs b/crates/cyrusc_codegen_llvm/src/builder/exprs.rs
index df5100bdf..8acd05d41 100644
--- a/crates/cyrusc_codegen_llvm/src/builder/exprs.rs
+++ b/crates/cyrusc_codegen_llvm/src/builder/exprs.rs
@@ -1133,7 +1133,7 @@ impl<'ll> CodeGenIRBuilder<'ll> {
                 let cir_pointee_type = lhs_rvalue.ty.pointer_inner().unwrap().clone();
 
                 let pointee_type: BasicTypeEnum<'ll> = if cir_pointee_type.is_void() {
-                    self.llvm_ctx.ptr_type(AddressSpace::default()).into()
+                    self.llvm_ctx.i8_type().into()
                 } else {
                     self.emit_type(cir_pointee_type).try_into().unwrap()
                 };
@@ -1153,7 +1153,7 @@ impl<'ll> CodeGenIRBuilder<'ll> {
         let cir_pointee_type = result_type.pointer_inner().unwrap().clone();
 
         let pointee_type: BasicTypeEnum<'ll> = if cir_pointee_type.is_void() {
-            self.llvm_ctx.ptr_type(AddressSpace::default()).into()
+            self.llvm_ctx.i8_type().into()
         } else {
             self.emit_type(cir_pointee_type).try_into().unwrap()
         };
@@ -1186,7 +1186,7 @@ impl<'ll> CodeGenIRBuilder<'ll> {
         let cir_pointee_type = result_type.pointer_inner().unwrap().clone();
 
         let pointee_type: BasicTypeEnum<'ll> = if cir_pointee_type.is_void() {
-            self.llvm_ctx.ptr_type(AddressSpace::default()).into()
+            self.llvm_ctx.i8_type().into()
         } else {
             self.emit_type(cir_pointee_type).try_into().unwrap()
         };
diff --git a/crates/cyrusc_codegen_llvm/src/builder/intrinsics.rs b/crates/cyrusc_codegen_llvm/src/builder/intrinsics.rs
index e09145d08..96099ed35 100644
--- a/crates/cyrusc_codegen_llvm/src/builder/intrinsics.rs
+++ b/crates/cyrusc_codegen_llvm/src/builder/intrinsics.rs
@@ -2,7 +2,7 @@
 // Copyright (c) 2026 The Cyrus Language
 
 use crate::builder::{
-    builder::CodeGenIRBuilder,
+    builder::{CodeGenIRBuilder, DebugLocationGuard},
     values::{InternalValue, InternalValueKind},
 };
 use cyrusc_internal::cir::{
@@ -23,6 +23,7 @@ use inkwell::{
 // These intrinsics published via builtin to user side.
 impl<'ll> CodeGenIRBuilder<'ll> {
     pub(crate) fn emit_builtin_call(&mut self, call: &CIRCall, builtin_spec: &TypedBuiltinSpec) -> InternalValue<'ll> {
+        let _guard = DebugLocationGuard::new(self.llvmbuilder.as_mut_ptr(), self.dctx.is_some());
         debug_assert!(builtin_spec.phase == TypedBuiltinPhase::Codegen);
         debug_assert!(builtin_spec.form == TypedBuiltinForm::Expr);
 
@@ -189,6 +190,7 @@ impl<'ll> CodeGenIRBuilder<'ll> {
     }
 
     pub(crate) fn emit_intrinsic_panic(&mut self, args: &[CIRExpr], loc: Loc) -> InternalValue<'ll> {
+        let _guard = DebugLocationGuard::new(self.llvmbuilder.as_mut_ptr(), self.dctx.is_some());
         let cir_void_ptr = CIRType::Pointer(Box::new(CIRType::Plain(PlainType::Void)));
 
         let ptr_type = self.llvm_ctx.ptr_type(inkwell::AddressSpace::default());
diff --git a/crates/cyrusc_codegen_llvm/src/builder/values.rs b/crates/cyrusc_codegen_llvm/src/builder/values.rs
index ae3ef96bd..16aafdec2 100644
--- a/crates/cyrusc_codegen_llvm/src/builder/values.rs
+++ b/crates/cyrusc_codegen_llvm/src/builder/values.rs
@@ -116,7 +116,10 @@ impl<'ll> CodeGenIRBuilder<'ll> {
             rvalue = InternalValue::new(rvalue.ty.clone(), InternalValueKind::RValue(widened.into()));
         }
 
-        self.llvmbuilder.build_store(ptr, rvalue.as_basic_value()).unwrap();
+        let store_inst = self.llvmbuilder.build_store(ptr, rvalue.as_basic_value()).unwrap();
+        if layout.align > 0 {
+            store_inst.set_alignment(layout.align).unwrap();
+        }
     }
 
     pub(crate) fn widen_int_arg(&self, value: InternalValue<'ll>, signed: bool) -> InternalValue<'ll> {
@@ -202,6 +205,22 @@ impl<'ll> CodeGenIRBuilder<'ll> {
                 let ty: BasicTypeEnum<'ll> = self.emit_type(internal_value.ty.clone()).try_into().unwrap();
                 let basic_value = self.llvmbuilder.build_load(ty, pointer_value, "rvalue").unwrap();
 
+                let load_inst = match basic_value {
+                    BasicValueEnum::ArrayValue(val) => val.as_instruction(),
+                    BasicValueEnum::IntValue(val) => val.as_instruction(),
+                    BasicValueEnum::FloatValue(val) => val.as_instruction(),
+                    BasicValueEnum::PointerValue(val) => val.as_instruction(),
+                    BasicValueEnum::StructValue(val) => val.as_instruction(),
+                    BasicValueEnum::VectorValue(val) => val.as_instruction(),
+                    _ => None,
+                };
+                if let Some(inst) = load_inst {
+                    let layout = self.tctx.layout_of(&internal_value.ty);
+                    if layout.align > 0 {
+                        inst.set_alignment(layout.align).unwrap();
+                    }
+                }
+
                 if internal_value.ty.is_bool() {
                     InternalValue::new(
                         internal_value.ty,
diff --git a/crates/cyrusc_codegen_llvm/src/llvm/debug_info.rs b/crates/cyrusc_codegen_llvm/src/llvm/debug_info.rs
index bdab78050..39546cfc5 100644
--- a/crates/cyrusc_codegen_llvm/src/llvm/debug_info.rs
+++ b/crates/cyrusc_codegen_llvm/src/llvm/debug_info.rs
@@ -606,6 +606,8 @@ pub unsafe fn debug_func_type(
 
     if let Some(ret) = ret_type {
         types.push(ret);
+    } else {
+        types.push(std::ptr::null_mut());
     }
 
     for p in params {