fix(data-pipeline): contain panics in combined FFI

AGENTS.md

@@ -73,7 +73,7 @@ libdatadog is integrated into many runtimes and languages via FFI, and runs in D
 - Bubble errors up to the library caller with detail — prefer structured error enums (e.g. `thiserror`) over opaque strings.
 - Stay free of global effects unless a feature requires them: no spawning threads, no globals, no reading environment variables behind the caller's back.
 - Care about performance, especially memory allocations on hot paths.
-- Panics across FFI boundaries are undefined behavior. FFI entry points must catch unwinds (e.g. `std::panic::catch_unwind`) and convert them into error returns rather than letting them propagate into the caller's runtime.
+- A panic that reaches an `extern "C"` boundary aborts the host process. FFI entry points must catch unwinds (e.g. `std::panic::catch_unwind`) and convert them into error returns rather than letting them propagate into the caller's runtime. Whether a release artifact gets panic containment is decided by `builder` alone, through its `catch_panic` feature (a default), which propagates to the `catch_panic` feature in `libdd-profiling-ffi/Cargo.toml`. Projects building their own flavor with `builder`'s default features off ask for `catch_panic` explicitly; leaving it out yields abort-on-panic semantics. The FFI examples are what verify containment is on for our own release process.
 - The C FFI does **not** offer C ABI backward-compatibility guarantees: callers (Datadog SDKs) pin to specific libdatadog versions, so `#[repr(C)]` layouts, function signatures, and enum variants may change between releases.
 
 ### Cryptography

builder/Cargo.toml

@@ -20,6 +20,7 @@ default = [
   "ddsketch",
   "ffe",
   "shared-runtime",
+  "catch_panic",
 ]
 crashtracker = []
 profiling = []
@@ -35,11 +36,11 @@ ddsketch = []
 ffe = []
 shared-runtime = []
 otel-thread-ctx = []
+catch_panic = []
 regex-lite = ["libdd-common/regex-lite"]
 
 [lib]
 bench = false
-test = false
 doctest = false
 
 [dependencies]

builder/src/bin/release.rs

@@ -9,6 +9,7 @@ use builder::builder::Builder;
 use builder::common::Common;
 #[cfg(feature = "crashtracker")]
 use builder::crashtracker::CrashTracker;
+use builder::features::{profiling_features, Selection};
 #[cfg(feature = "profiling")]
 use builder::profiling::Profiling;
 use builder::utils::project_root;
@@ -54,34 +55,7 @@ pub fn main() {
         host.clone()
     };
 
-    #[allow(clippy::vec_init_then_push)]
-    let features = {
-        #[allow(unused_mut)]
-        let mut f: Vec<String> = vec![];
-        #[cfg(feature = "telemetry")]
-        f.push("ddtelemetry-ffi".to_string());
-        #[cfg(feature = "data-pipeline")]
-        f.push("data-pipeline-ffi".to_string());
-        #[cfg(feature = "data-pipeline-compression")]
-        f.push("data-pipeline-compression".to_string());
-        #[cfg(feature = "crashtracker")]
-        f.push("crashtracker-ffi".to_string());
-        #[cfg(feature = "symbolizer")]
-        f.push("symbolizer".to_string());
-        #[cfg(feature = "library-config")]
-        f.push("datadog-library-config-ffi".to_string());
-        #[cfg(feature = "log")]
-        f.push("datadog-log-ffi".to_string());
-        #[cfg(feature = "ddsketch")]
-        f.push("ddsketch-ffi".to_string());
-        #[cfg(feature = "ffe")]
-        f.push("libdd-ffe-ffi".to_string());
-        #[cfg(feature = "shared-runtime")]
-        f.push("shared-runtime".to_string());
-        #[cfg(feature = "otel-thread-ctx")]
-        f.push("otel-thread-ctx-ffi".to_string());
-        f
-    };
+    let features = profiling_features(&Selection::from_cargo_features());
 
     let mut builder = Builder::new(
         source_path.to_str().unwrap(),

builder/src/builder.rs

@@ -40,7 +40,7 @@ use crate::utils::{file_replace, project_root};
 ///         Ok(())
 ///     }
 /// }
-/// let mut builder = Builder::new("source", "target", "arch", "features", "profile", "version");
+/// let mut builder = Builder::new("source", "target", "arch", "profile", "features", "version");
 /// let core = Box::new(Core {
 ///     version: builder.version.clone(),
 /// });