diff --git a/src/lints/function_abi_no_longer_unwind.ron b/src/lints/function_abi_no_longer_unwind.ron
new file mode 100644
index 00000000..2e699cb6
--- /dev/null
+++ b/src/lints/function_abi_no_longer_unwind.ron
@@ -0,0 +1,51 @@
+SemverQuery(
+    id: "function_abi_no_longer_unwind",
+    human_readable_name: "function abi no longer unwind",
+    description: "A pub fn changed from an unwind-capable ABI to the same-named ABI without unwind. If that function causes an unwind (e.g. by panicking), its behavior is now undefined.",
+    required_update: Major,
+    reference_link: Some("https://rust-lang.github.io/rfcs/2945-c-unwind-abi.html"),
+    query: r#"
+    {
+        CrateDiff {
+            baseline {
+                item {
+                    ... on Function {
+                        visibility_limit @filter(op: "=", value: ["$public"])
+
+                        abi_: abi {
+                            name @tag
+                            raw_name @output
+                            unwind @filter(op: "=", value: ["$true"])
+                        }
+                    }
+                }
+            }
+            current {
+                item {
+                    ... on Function {
+                        visibility_limit @filter(op: "=", value: ["$public"])
+
+                        name @output
+
+                        new_abi_: abi {
+                            name @filter(op: "=", value: ["%name"])
+                            raw_name @output
+                            unwind @filter(op: "!=", value: ["$true"])
+                        }
+
+                        span_: span @optional {
+                            filename @output
+                            begin_line @output
+                        }
+                    }
+                }
+            }
+        }
+    }"#,
+    arguments: {
+        "public": "public",
+        "true": true,
+    },
+    error_message: "A pub fn changed from an unwind-capable ABI to the same-named ABI without unwind. If that function causes an unwind (e.g. by panicking), its behavior is now undefined.",
+    per_result_error_template: Some("pub fn {{name}} changed ABI from {{abi_raw_name}} to {{new_abi_raw_name}} in {{span_filename}}:{{span_begin_line}}"),
+)
diff --git a/src/query.rs b/src/query.rs
index ff59aef6..f08045ac 100644
--- a/src/query.rs
+++ b/src/query.rs
@@ -476,6 +476,7 @@ macro_rules! add_lints {
 }
 
 add_lints!(
+    function_abi_no_longer_unwind,
     pub_module_level_const_now_doc_hidden,
     enum_struct_variant_field_now_doc_hidden,
     enum_tuple_variant_field_now_doc_hidden,
diff --git a/test_crates/function_abi_no_longer_unwind/new/Cargo.toml b/test_crates/function_abi_no_longer_unwind/new/Cargo.toml
new file mode 100644
index 00000000..0cfe78f0
--- /dev/null
+++ b/test_crates/function_abi_no_longer_unwind/new/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "function_abi_no_longer_unwind"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/test_crates/function_abi_no_longer_unwind/new/src/lib.rs b/test_crates/function_abi_no_longer_unwind/new/src/lib.rs
new file mode 100644
index 00000000..88f0a4f6
--- /dev/null
+++ b/test_crates/function_abi_no_longer_unwind/new/src/lib.rs
@@ -0,0 +1 @@
+pub extern "C" fn unwind_function_becomes_non_unwind() {}
diff --git a/test_crates/function_abi_no_longer_unwind/old/Cargo.toml b/test_crates/function_abi_no_longer_unwind/old/Cargo.toml
new file mode 100644
index 00000000..0cfe78f0
--- /dev/null
+++ b/test_crates/function_abi_no_longer_unwind/old/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "function_abi_no_longer_unwind"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/test_crates/function_abi_no_longer_unwind/old/src/lib.rs b/test_crates/function_abi_no_longer_unwind/old/src/lib.rs
new file mode 100644
index 00000000..3921c503
--- /dev/null
+++ b/test_crates/function_abi_no_longer_unwind/old/src/lib.rs
@@ -0,0 +1 @@
+pub extern "C-unwind" fn unwind_function_becomes_non_unwind() {}
diff --git a/test_outputs/function_abi_no_longer_unwind.output.ron b/test_outputs/function_abi_no_longer_unwind.output.ron
new file mode 100644
index 00000000..d3774dd0
--- /dev/null
+++ b/test_outputs/function_abi_no_longer_unwind.output.ron
@@ -0,0 +1,11 @@
+{
+    "./test_crates/function_abi_no_longer_unwind/": [
+        {
+            "abi_raw_name": String("C-unwind"),
+            "name": String("unwind_function_becomes_non_unwind"),
+            "new_abi_raw_name": String("C"),
+            "span_begin_line": Uint64(1),
+            "span_filename": String("src/lib.rs"),
+        },
+    ],
+}