Restore behavior when primary bundle is missing

compiler/rustc_error_messages/src/lib.rs

@@ -135,7 +135,10 @@ pub fn fluent_bundle(
 
  let fallback_locale = langid!("en-US");
  let requested_fallback_locale = requested_locale.as_ref() == Some(&fallback_locale);
-
+ trace!(?requested_fallback_locale);
+ if requested_fallback_locale && additional_ftl_path.is_none() {
+ return Ok(None);
+ }
  // If there is only `-Z additional-ftl-path`, assume locale is "en-US", otherwise use user
  // provided locale.
  let locale = requested_locale.clone().unwrap_or(fallback_locale);
@@ -153,7 +156,7 @@ pub fn fluent_bundle(
  bundle.set_use_isolating(with_directionality_markers);
 
  // If the user requests the default locale then don't try to load anything.
- if !requested_fallback_locale && let Some(requested_locale) = requested_locale {
+ if let Some(requested_locale) = requested_locale {
  let mut found_resources = false;
  for sysroot in user_provided_sysroot.iter_mut().chain(sysroot_candidates.iter_mut()) {
  sysroot.push("share");

compiler/rustc_errors/src/translation.rs

@@ -1,4 +1,4 @@
-use crate::error::TranslateError;
+use crate::error::{TranslateError, TranslateErrorKind};
 use crate::snippet::Style;
 use crate::{DiagnosticArg, DiagnosticMessage, FluentBundle};
 use rustc_data_structures::sync::Lrc;
@@ -95,6 +95,16 @@ pub trait Translate {
  // The primary bundle was present and translation succeeded
  Some(Ok(t)) => t,
 
+ // If `translate_with_bundle` returns `Err` with the primary bundle, this is likely
+ // just that the primary bundle doesn't contain the message being translated, so
+ // proceed to the fallback bundle.
+ Some(Err(
+ primary @ TranslateError::One {
+ kind: TranslateErrorKind::MessageMissing, ..
+ },
+ )) => translate_with_bundle(self.fallback_fluent_bundle())
+ .map_err(|fallback| primary.and(fallback))?,
+
  // Always yeet out for errors on debug (unless
  // `RUSTC_TRANSLATION_NO_DEBUG_ASSERT` is set in the environment - this allows
  // local runs of the test suites, of builds with debug assertions, to test the
@@ -106,9 +116,8 @@ pub trait Translate {
  do yeet primary
  }
 
- // If `translate_with_bundle` returns `Err` with the primary bundle, this is likely
- // just that the primary bundle doesn't contain the message being translated or
- // something else went wrong) so proceed to the fallback bundle.
+ // ..otherwise, for end users, an error about this wouldn't be useful or actionable, so
+ // just hide it and try with the fallback bundle.
  Some(Err(primary)) => translate_with_bundle(self.fallback_fluent_bundle())
  .map_err(|fallback| primary.and(fallback))?,
 

tests/ui/issues/issue-106755.rs

@@ -0,0 +1,19 @@
+// compile-flags:-Ztranslate-lang=en_US
+
+#![feature(negative_impls)]
+#![feature(marker_trait_attr)]
+
+#[marker]
+trait MyTrait {}
+
+struct TestType<T>(::std::marker::PhantomData<T>);
+
+unsafe impl<T: MyTrait + 'static> Send for TestType<T> {}
+
+impl<T: MyTrait> !Send for TestType<T> {} //~ ERROR found both positive and negative implementation
+
+unsafe impl<T: 'static> Send for TestType<T> {} //~ ERROR conflicting implementations
+
+impl !Send for TestType<i32> {}
+
+fn main() {}

tests/ui/issues/issue-106755.stderr

@@ -0,0 +1,22 @@
+error[E0751]: found both positive and negative implementation of trait `Send` for type `TestType<_>`:
+ --> $DIR/issue-106755.rs:13:1
+ |
+LL | unsafe impl<T: MyTrait + 'static> Send for TestType<T> {}
+ | ------------------------------------------------------ positive implementation here
+LL |
+LL | impl<T: MyTrait> !Send for TestType<T> {}
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ negative implementation here
+
+error[E0119]: conflicting implementations of trait `Send` for type `TestType<_>`
+ --> $DIR/issue-106755.rs:15:1
+ |
+LL | unsafe impl<T: MyTrait + 'static> Send for TestType<T> {}
+ | ------------------------------------------------------ first implementation here
+...
+LL | unsafe impl<T: 'static> Send for TestType<T> {}
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `TestType<_>`
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0119, E0751.
+For more information about an error, try `rustc --explain E0119`.