commit 24160d5f1691518d24b8f2bcc28ca787b974392e
author Lukasz Anforowicz <lukasza@google.com> Wed Oct 19 06:45:45 2022 -0700
committer Copybara-Service <copybara-worker@google.com> Wed Oct 19 06:46:25 2022 -0700
tree 3b2595dcb2bd61730f8b22f0e3ea99f1be4acd2f
parent 76e262395b059e850e16471b292823df5e8cd2a7

Error out in `cc_bindings_from_rs` if unsupported `panic=unwind` is used.

PiperOrigin-RevId: 482191088

cc_bindings_from_rs/cc_bindings_from_rs.rs

diff --git a/cc_bindings_from_rs/cc_bindings_from_rs.rs b/cc_bindings_from_rs/cc_bindings_from_rs.rs
index 8cb1c8b..c44002a 100644
--- a/cc_bindings_from_rs/cc_bindings_from_rs.rs
+++ b/cc_bindings_from_rs/cc_bindings_from_rs.rs
@@ -167,7 +167,7 @@
 }
 
 fn run_with_tcx(cmdline: &Cmdline, tcx: TyCtxt) -> anyhow::Result<()> {
-    let bindings = GeneratedBindings::generate(tcx);
+    let bindings = GeneratedBindings::generate(tcx)?;
     write_file(&cmdline.h_out, cc_tokens_to_formatted_string(bindings.h_body)?.as_str())
 }
 
@@ -238,7 +238,13 @@
     struct TestArgs {
         h_path: Option<String>,
         extra_crubit_args: Vec<String>,
+
+        /// Arg for the following `rustc` flag: `--codegen=panic=<arg>`.
+        panic_mechanism: String,
+
+        /// Other `rustc` flags.
         extra_rustc_args: Vec<String>,
+
         tempdir: TempDir,
     }
 
@@ -255,6 +261,7 @@
             Ok(Self {
                 h_path: None,
                 extra_crubit_args: vec![],
+                panic_mechanism: "abort".to_string(),
                 extra_rustc_args: vec![],
                 tempdir: tempdir()?,
             })
@@ -267,6 +274,13 @@
             self
         }
 
+        /// Replaces the default `--codegen=panic=abort` with the specified
+        /// `panic_mechanism`.
+        fn with_panic_mechanism(mut self, panic_mechanism: &str) -> Self {
+            self.panic_mechanism = panic_mechanism.to_string();
+            self
+        }
+
         /// Appends `extra_rustc_args` at the end of the cmdline (i.e. as
         /// additional rustc args, in addition to `--sysroot`,
         /// `--crate-type=...`, etc.).
@@ -319,6 +333,7 @@
             args.extend(self.extra_crubit_args.iter().cloned());
             args.extend([
                 "--".to_string(),
+                format!("--codegen=panic={}", &self.panic_mechanism),
                 "--crate-type=lib".to_string(),
                 format!("--sysroot={}", get_sysroot_for_testing().display()),
                 rs_input_path.display().to_string(),
@@ -399,6 +414,19 @@
     }
 
     #[test]
+    fn test_rustc_unsupported_panic_mechanism() -> anyhow::Result<()> {
+        // Tests that `panic=unwind` results in an error.
+        let err = TestArgs::default_args()?
+            .with_panic_mechanism("unwind")
+            .run()
+            .expect_err("panic=unwind should trigger an error");
+
+        let msg = format!("{err:#}");
+        assert_eq!("No support for panic=unwind strategy (b/254049425)", msg);
+        Ok(())
+    }
+
+    #[test]
     fn test_invalid_h_out_path() -> anyhow::Result<()> {
         // Tests not only the specific problem of an invalid `--h-out` argument, but
         // also tests that errors from `run_with_tcx` are propagated.