From 76de6001641073f0bfdabcad53cc710cee03e7a6 Mon Sep 17 00:00:00 2001
From: Emil Tsalapatis <etsal@meta.com>
Date: Mon, 16 Dec 2024 08:49:08 -0800
Subject: [PATCH] fix missing rerun-if-changed statements

---
 rust/scx_utils/src/bpf_builder.rs | 38 +++++++++++++++++++++----------
 1 file changed, 26 insertions(+), 12 deletions(-)

diff --git a/rust/scx_utils/src/bpf_builder.rs b/rust/scx_utils/src/bpf_builder.rs
index e8cbacbfe..2ff64a522 100644
--- a/rust/scx_utils/src/bpf_builder.rs
+++ b/rust/scx_utils/src/bpf_builder.rs
@@ -366,6 +366,8 @@ impl BpfBuilder {
             .clang_args(&self.cflags)
             .generate(&skel_path)?;
 
+        self.gen_cargo_reruns(None)?;
+
         Ok(())
     }
 
@@ -403,26 +405,38 @@ impl BpfBuilder {
         Ok(())
     }
 
-    /// Build and generate the enabled bindings.
-    pub fn build(&self) -> Result<()> {
-        let mut deps = BTreeSet::new();
-
-        self.input_insert_deps(&mut deps);
-
-        self.bindgen_bpf_intf()?;
-        self.gen_bpf_skel(&mut deps)?;
-
+    fn gen_cargo_reruns(&self, dependencies: Option<&BTreeSet<String>>) -> Result<()> {
         println!("cargo:rerun-if-env-changed=BPF_CLANG");
         println!("cargo:rerun-if-env-changed=BPF_CFLAGS");
         println!("cargo:rerun-if-env-changed=BPF_BASE_CFLAGS");
         println!("cargo:rerun-if-env-changed=BPF_EXTRA_CFLAGS_PRE_INCL");
         println!("cargo:rerun-if-env-changed=BPF_EXTRA_CFLAGS_POST_INCL");
-        for dep in deps.iter() {
-            println!("cargo:rerun-if-changed={}", dep);
-        }
+        match dependencies {
+            Some(deps) => {
+                for dep in deps.iter() {
+                    println!("cargo:rerun-if-changed={}", dep);
+                }
+            }
+
+            None => (),
+        };
+
         for source in self.sources.iter() {
             println!("cargo:rerun-if-changed={}", source);
         }
+
+        Ok(())
+    }
+
+    /// Build and generate the enabled bindings.
+    pub fn build(&self) -> Result<()> {
+        let mut deps = BTreeSet::new();
+
+        self.input_insert_deps(&mut deps);
+
+        self.bindgen_bpf_intf()?;
+        self.gen_bpf_skel(&mut deps)?;
+        self.gen_cargo_reruns(Some(&deps))?;
         Ok(())
     }
 }