commit b8279db2225cf423ae7489095fba20d31e49e301
author Lukasz Anforowicz <lukasza@google.com> Thu Sep 22 07:40:55 2022 -0700
committer Copybara-Service <copybara-worker@google.com> Thu Sep 22 07:41:43 2022 -0700
tree 1fcb3327b06715add4cfce61ba36765a6c14af34
parent bf5a4ee5a5b00e4c838aaf68deb5d3fa5c45e9f2

Wrap `CompilerCallbacks::result` in an `Option`.

PiperOrigin-RevId: 476092755

cc_bindings_from_rs/main.rs

diff --git a/cc_bindings_from_rs/main.rs b/cc_bindings_from_rs/main.rs
index 1b89ce8..d297f12 100644
--- a/cc_bindings_from_rs/main.rs
+++ b/cc_bindings_from_rs/main.rs
@@ -68,16 +68,20 @@
     /// its result via `CompilerCallbacks::into_result`.
     pub struct CompilerCallbacks<'a> {
         cmdline: &'a Cmdline,
-        result: anyhow::Result<()>,
+        result: Option<anyhow::Result<()>>,
     }
 
     impl<'a> CompilerCallbacks<'a> {
         pub fn new(cmdline: &'a Cmdline) -> Self {
-            Self { cmdline, result: Ok(()) }
+            Self { cmdline, result: None }
         }
 
         pub fn into_result(self) -> anyhow::Result<()> {
-            self.result
+            assert!(
+                self.result.is_some(),
+                "CompilerCallbacks::run_main should have been called by now"
+            );
+            self.result.unwrap()
         }
     }
 
@@ -87,15 +91,16 @@
             _compiler: &Compiler,
             queries: &'tcx Queries<'tcx>,
         ) -> rustc_driver::Compilation {
-            let rustc_result =
-                enter_tcx(queries, |tcx| crate::bindings_generation::main(self.cmdline, tcx));
+            let rustc_result = enter_tcx(queries, |tcx| {
+                assert!(self.result.is_none(), "after_analysis should only run once");
+                self.result = Some(crate::bindings_generation::main(self.cmdline, tcx));
+            });
 
             // `expect`ing no errors in `rustc_result`, because `after_analysis` is only
             // called by `rustc_driver` if earlier compiler analysis was successful
             // (which as the *last* compilation phase presumably covers *all*
             // errors).
-            self.result = rustc_result
-                .expect("Expecting no compile errors inside `after_analysis` callback.");
+            rustc_result.expect("Expecting no compile errors inside `after_analysis` callback.");
 
             rustc_driver::Compilation::Stop
         }