Ensure that crates are linked with compatible panic-in-drop settings

compiler/rustc_metadata/src/dependency_format.rs

@@ -400,12 +400,12 @@ fn verify_ok(tcx: TyCtxt<'_>, list: &[Linkage]) {
                 continue;
             }
             let cnum = CrateNum::new(i + 1);
-            let found_strategy = tcx.panic_strategy(cnum);
-            let is_compiler_builtins = tcx.is_compiler_builtins(cnum);
-            if is_compiler_builtins || desired_strategy == found_strategy {
+            if tcx.is_compiler_builtins(cnum) {
                 continue;
             }
 
+            let found_strategy = tcx.panic_strategy(cnum);
+            if desired_strategy != found_strategy {
                 sess.err(&format!(
                     "the crate `{}` is compiled with the \
                                panic strategy `{}` which is \
@@ -416,5 +416,19 @@ fn verify_ok(tcx: TyCtxt<'_>, list: &[Linkage]) {
                     desired_strategy.desc()
                 ));
             }
+
+            let found_drop_strategy = tcx.panic_in_drop_strategy(cnum);
+            if tcx.sess.opts.debugging_opts.panic_in_drop != found_drop_strategy {
+                sess.err(&format!(
+                    "the crate `{}` is compiled with the \
+                               panic-in-drop strategy `{}` which is \
+                               incompatible with this crate's \
+                               strategy of `{}`",
+                    tcx.crate_name(cnum),
+                    found_drop_strategy.desc(),
+                    tcx.sess.opts.debugging_opts.panic_in_drop.desc()
+                ));
+            }
+        }
     }
 }

compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs

@@ -160,6 +160,7 @@ provide! { <'tcx> tcx, def_id, other, cdata,
     has_panic_handler => { cdata.root.has_panic_handler }
     is_profiler_runtime => { cdata.root.profiler_runtime }
     panic_strategy => { cdata.root.panic_strategy }
+    panic_in_drop_strategy => { cdata.root.panic_in_drop_strategy }
     extern_crate => {
         let r = *cdata.extern_crate.lock();
         r.map(|c| &*tcx.arena.alloc(c))

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -691,6 +691,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             hash: tcx.crate_hash(LOCAL_CRATE),
             stable_crate_id: tcx.def_path_hash(LOCAL_CRATE.as_def_id()).stable_crate_id(),
             panic_strategy: tcx.sess.panic_strategy(),
+            panic_in_drop_strategy: tcx.sess.opts.debugging_opts.panic_in_drop,
             edition: tcx.sess.edition(),
             has_global_allocator: tcx.has_global_allocator(LOCAL_CRATE),
             has_panic_handler: tcx.has_panic_handler(LOCAL_CRATE),

compiler/rustc_metadata/src/rmeta/mod.rs

@@ -204,6 +204,7 @@ crate struct CrateRoot<'tcx> {
     hash: Svh,
     stable_crate_id: StableCrateId,
     panic_strategy: PanicStrategy,
+    panic_in_drop_strategy: PanicStrategy,
     edition: Edition,
     has_global_allocator: bool,
     has_panic_handler: bool,

compiler/rustc_middle/src/query/mod.rs

@@ -1159,6 +1159,10 @@ rustc_queries! {
         fatal_cycle
         desc { "query a crate's configured panic strategy" }
     }
+    query panic_in_drop_strategy(_: CrateNum) -> PanicStrategy {
+        fatal_cycle
+        desc { "query a crate's configured panic-in-drop strategy" }
+    }
     query is_no_builtins(_: CrateNum) -> bool {
         fatal_cycle
         desc { "test whether a crate has `#![no_builtins]`" }