From 7e74c9cdbfcfaf5755da291292ad8287dc6aa34b Mon Sep 17 00:00:00 2001
From: Lee ByeongJun <lbj199874@gmail.com>
Date: Fri, 22 Aug 2025 00:16:41 +0900
Subject: [PATCH 1/2] fix: handle pattern type

---
 .../src/debuginfo/metadata.rs                 | 39 +++++++++++++++++++
 .../pattern_types/ice-debuginfo-145514.rs     | 17 ++++++++
 2 files changed, 56 insertions(+)
 create mode 100644 tests/ui/type/pattern_types/ice-debuginfo-145514.rs

diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 0e9dbfba658d2..3b30530a2e8dc 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -380,6 +380,39 @@ fn build_dyn_type_di_node<'ll, 'tcx>(
     }
 }
 
+/// Create debuginfo for pattern types like `pat::pattern_type!(i8 is 1..=2)`.
+/// Pattern types are refinement types that have the same runtime representation
+/// as their underlying type, so we generate debuginfo that represents them
+/// as a typedef to the underlying type with the pattern type's name.
+fn build_pattern_type_di_node<'ll, 'tcx>(
+    cx: &CodegenCx<'ll, 'tcx>,
+    inner_ty: Ty<'tcx>,
+    _unique_type_id: UniqueTypeId<'tcx>,
+    pattern_ty: Ty<'tcx>,
+) -> DINodeCreationResult<'ll> {
+    debug!("build_pattern_type_di_node: {:?}", pattern_ty);
+
+    // Get the debuginfo for the underlying type
+    let inner_di_node = type_di_node(cx, inner_ty);
+
+    // Create a typedef that points to the underlying type but uses the pattern type's name
+    let type_name = compute_debuginfo_type_name(cx.tcx, pattern_ty, false);
+
+    let typedef_di_node = unsafe {
+        llvm::LLVMRustDIBuilderCreateTypedef(
+            DIB(cx),
+            inner_di_node,
+            type_name.as_ptr().cast(),
+            type_name.len(),
+            unknown_file_metadata(cx),
+            UNKNOWN_LINE_NUMBER,
+            NO_SCOPE_METADATA,
+        )
+    };
+
+    DINodeCreationResult { di_node: typedef_di_node, already_stored_in_typemap: false }
+}
+
 /// Create debuginfo for `[T]` and `str`. These are unsized.
 ///
 /// NOTE: We currently emit just emit the debuginfo for the element type here
@@ -463,6 +496,12 @@ pub(crate) fn type_di_node<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>, t: Ty<'tcx>) ->
             AdtKind::Enum => enums::build_enum_type_di_node(cx, unique_type_id),
         },
         ty::Tuple(_) => build_tuple_type_di_node(cx, unique_type_id),
+        ty::Pat(inner_ty, _) => {
+            // Issue #145514: Pattern types are refinement types that constrain their inner type.
+            // For debuginfo purposes, we treat them as their underlying type since
+            // they have the same runtime representation.
+            build_pattern_type_di_node(cx, inner_ty, unique_type_id, t)
+        }
         _ => bug!("debuginfo: unexpected type in type_di_node(): {:?}", t),
     };
 
diff --git a/tests/ui/type/pattern_types/ice-debuginfo-145514.rs b/tests/ui/type/pattern_types/ice-debuginfo-145514.rs
new file mode 100644
index 0000000000000..819b4176089bc
--- /dev/null
+++ b/tests/ui/type/pattern_types/ice-debuginfo-145514.rs
@@ -0,0 +1,17 @@
+// Regression test for issue #145514
+// compile-flags: -C debuginfo=2
+//@ build-pass
+
+#![feature(pattern_types, pattern_type_macro, pattern_type_range_trait)]
+
+use std::io::{Write, stderr};
+use std::pat;
+
+type SmallInt = pat::pattern_type!(i8 is 1..=2);
+
+fn main() {
+    let s: SmallInt = unsafe { core::mem::transmute(1i8) };
+    let _ = stderr().lock().write_fmt(format_args!("{}\n", unsafe {
+        core::mem::transmute::<_, i8>(s)
+    }));
+}

From 3805a3f9d905601a93e36dc893f8cd6967d6b491 Mon Sep 17 00:00:00 2001
From: Lee ByeongJun <lbj199874@gmail.com>
Date: Fri, 22 Aug 2025 00:53:06 +0900
Subject: [PATCH 2/2] utiliize unique type id

---
 compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 3b30530a2e8dc..bd59a72e0aba4 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -387,7 +387,7 @@ fn build_dyn_type_di_node<'ll, 'tcx>(
 fn build_pattern_type_di_node<'ll, 'tcx>(
     cx: &CodegenCx<'ll, 'tcx>,
     inner_ty: Ty<'tcx>,
-    _unique_type_id: UniqueTypeId<'tcx>,
+    unique_type_id: UniqueTypeId<'tcx>,
     pattern_ty: Ty<'tcx>,
 ) -> DINodeCreationResult<'ll> {
     debug!("build_pattern_type_di_node: {:?}", pattern_ty);
@@ -395,6 +395,8 @@ fn build_pattern_type_di_node<'ll, 'tcx>(
     // Get the debuginfo for the underlying type
     let inner_di_node = type_di_node(cx, inner_ty);
 
+    return_if_di_node_created_in_meantime!(cx, unique_type_id);
+
     // Create a typedef that points to the underlying type but uses the pattern type's name
     let type_name = compute_debuginfo_type_name(cx.tcx, pattern_ty, false);