diff --git a/compiler-core/src/ast/constant.rs b/compiler-core/src/ast/constant.rs
index dbc71ec..0d90904 100644
--- a/compiler-core/src/ast/constant.rs
+++ b/compiler-core/src/ast/constant.rs
@@ -638,6 +638,25 @@ impl<A> Constant<A> {
         }
     }
 
+    #[must_use]
+    pub fn with_location(mut self, new_location: SrcSpan) -> Self {
+        match &mut self {
+            Constant::Int { location, .. }
+            | Constant::List { location, .. }
+            | Constant::Float { location, .. }
+            | Constant::Tuple { location, .. }
+            | Constant::String { location, .. }
+            | Constant::Record { location, .. }
+            | Constant::RecordUpdate { location, .. }
+            | Constant::BitArray { location, .. }
+            | Constant::Var { location, .. }
+            | Constant::Invalid { location, .. }
+            | Constant::Todo { location, .. }
+            | Constant::BinaryOperator { location, .. } => *location = new_location,
+        }
+        self
+    }
+
     #[must_use]
     pub fn can_have_multiple_per_line(&self) -> bool {
         match self {
diff --git a/compiler-core/src/type_/guard.rs b/compiler-core/src/type_/guard.rs
index 0a1ff48..890890f 100644
--- a/compiler-core/src/type_/guard.rs
+++ b/compiler-core/src/type_/guard.rs
@@ -320,7 +320,8 @@ impl<'expression_typer, 'env, 'module> GuardTyper<'expression_typer, 'env, 'modu
             }
 
             ValueConstructorVariant::ModuleConstant { literal, .. } => {
-                return Ok(ClauseGuard::Constant(literal.clone()));
+                let literal = literal.clone().with_location(location);
+                return Ok(ClauseGuard::Constant(literal));
             }
         };
 
diff --git a/compiler-core/src/type_/tests/guards.rs b/compiler-core/src/type_/tests/guards.rs
index aa2afef..c68741d 100644
--- a/compiler-core/src/type_/tests/guards.rs
+++ b/compiler-core/src/type_/tests/guards.rs
@@ -87,3 +87,42 @@ pub fn main(wibble: wibble.Wibble) {
         vec![("main", "fn(Wibble) -> Bool")]
     );
 }
+
+#[test]
+fn constant_with_wrong_type_in_guard() {
+    assert_module_error!(
+        r#"
+pub type Wibble {
+  Wibble(String)
+}
+
+pub const constant = Wibble("Hi")
+
+pub fn main() {
+  let wibble = "wibble"
+  case 1 {
+    _ if wibble == constant -> Nil
+    _ -> Nil
+  }
+}
+"#
+    );
+}
+
+#[test]
+fn unqualified_imported_constant_with_wrong_type_in_guard() {
+    assert_module_error!(
+        ("wibble", "pub const constant = 1"),
+        r#"
+import wibble.{constant}
+
+pub fn main() {
+  let wibble = "wibble"
+  case 1 {
+    _ if wibble == constant -> Nil
+    _ -> Nil
+  }
+}
+"#
+    );
+}
diff --git a/compiler-core/src/type_/tests/snapshots/gleam_core__type___tests__guards__constant_with_wrong_type_in_guard.snap b/compiler-core/src/type_/tests/snapshots/gleam_core__type___tests__guards__constant_with_wrong_type_in_guard.snap
new file mode 100644
index 0000000..bef7301
--- /dev/null
+++ b/compiler-core/src/type_/tests/snapshots/gleam_core__type___tests__guards__constant_with_wrong_type_in_guard.snap
@@ -0,0 +1,35 @@
+---
+source: compiler-core/src/type_/tests/guards.rs
+expression: "\npub type Wibble {\n  Wibble(String)\n}\n\npub const constant = Wibble(\"Hi\")\n\npub fn main() {\n  let wibble = \"wibble\"\n  case 1 {\n    _ if wibble == constant -> Nil\n    _ -> Nil\n  }\n}\n"
+---
+----- SOURCE CODE
+
+pub type Wibble {
+  Wibble(String)
+}
+
+pub const constant = Wibble("Hi")
+
+pub fn main() {
+  let wibble = "wibble"
+  case 1 {
+    _ if wibble == constant -> Nil
+    _ -> Nil
+  }
+}
+
+
+----- ERROR
+error: Type mismatch
+   ┌─ /src/one/two.gleam:11:20
+   │
+11 │     _ if wibble == constant -> Nil
+   │                    ^^^^^^^^
+
+Expected type:
+
+    String
+
+Found type:
+
+    Wibble
diff --git a/compiler-core/src/type_/tests/snapshots/gleam_core__type___tests__guards__unqualified_imported_constant_with_wrong_type_in_guard.snap b/compiler-core/src/type_/tests/snapshots/gleam_core__type___tests__guards__unqualified_imported_constant_with_wrong_type_in_guard.snap
new file mode 100644
index 0000000..2b75bd3
--- /dev/null
+++ b/compiler-core/src/type_/tests/snapshots/gleam_core__type___tests__guards__unqualified_imported_constant_with_wrong_type_in_guard.snap
@@ -0,0 +1,35 @@
+---
+source: compiler-core/src/type_/tests/guards.rs
+expression: "\nimport wibble.{constant}\n\npub fn main() {\n  let wibble = \"wibble\"\n  case 1 {\n    _ if wibble == constant -> Nil\n    _ -> Nil\n  }\n}\n"
+---
+----- SOURCE CODE
+-- wibble.gleam
+pub const constant = 1
+
+-- main.gleam
+
+import wibble.{constant}
+
+pub fn main() {
+  let wibble = "wibble"
+  case 1 {
+    _ if wibble == constant -> Nil
+    _ -> Nil
+  }
+}
+
+
+----- ERROR
+error: Type mismatch
+  ┌─ /src/one/two.gleam:7:20
+  │
+7 │     _ if wibble == constant -> Nil
+  │                    ^^^^^^^^
+
+Expected type:
+
+    String
+
+Found type:
+
+    Int