add span information to autodiff compile time errors

Author: ZuseZ4

compiler/rustc_ast/src/expand/autodiff_attrs.rs

@@ -6,6 +6,8 @@
 use std::fmt::{self, Display, Formatter};
 use std::str::FromStr;
 
+use rustc_span::Span;
+
 use crate::expand::{Decodable, Encodable, HashStable_Generic};
 use crate::ptr::P;
 use crate::{Ty, TyKind};
@@ -85,6 +87,7 @@ pub struct AutoDiffItem {
     /// The name of the function being generated
     pub target: String,
     pub attrs: AutoDiffAttrs,
+    pub span: Span,
 }
 
 #[derive(Clone, Eq, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)]
@@ -276,8 +279,8 @@ impl AutoDiffAttrs {
         !matches!(self.mode, DiffMode::Error | DiffMode::Source)
     }
 
-    pub fn into_item(self, source: String, target: String) -> AutoDiffItem {
-        AutoDiffItem { source, target, attrs: self }
+    pub fn into_item(self, source: String, target: String, span: Span) -> AutoDiffItem {
+        AutoDiffItem { source, target, attrs: self, span }
     }
 }
 

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -419,11 +419,12 @@ fn generate_lto_work<B: ExtraBackendMethods>(
     } else {
         if !autodiff.is_empty() {
             let dcx = cgcx.create_dcx();
+            let span = autodiff[0].span;
             if cgcx.crate_types.contains(&CrateType::Rlib) {
-                dcx.handle().emit_fatal(AutodiffLibraryBuild {});
+                dcx.handle().span_fatal(AutodiffLibraryBuild { span });
             }
             if cgcx.lto != Lto::Fat {
-                dcx.handle().emit_fatal(AutodiffWithoutLto {});
+                dcx.handle().emit_fatal(AutodiffWithoutLto { span });
             }
         }
         assert!(needs_fat_lto.is_empty());

compiler/rustc_codegen_ssa/src/errors.rs

@@ -39,11 +39,17 @@ pub(crate) struct CguNotRecorded<'a> {
 
 #[derive(Diagnostic)]
 #[diag(codegen_ssa_autodiff_without_lto)]
-pub struct AutodiffWithoutLto;
+pub struct AutodiffWithoutLto {
+    #[primary_span]
+    pub span: Span,
+}
 
 #[derive(Diagnostic)]
 #[diag(codegen_ssa_autodiff_lib_unsupported)]
-pub struct AutodiffLibraryBuild;
+pub struct AutodiffLibraryBuild {
+    #[primary_span]
+    pub span: Span,
+}
 
 #[derive(Diagnostic)]
 #[diag(codegen_ssa_unknown_reuse_kind)]

compiler/rustc_monomorphize/src/partitioning/autodiff.rs

@@ -120,15 +120,16 @@ pub(crate) fn find_autodiff_source_functions<'tcx>(
             None => continue,
         };
 
-        debug!("source_id: {:?}", inst.def_id());
+        let source_def_id = inst.def_id();
+        debug!("source_id: {:?}", source_def_id);
         let fn_ty = inst.ty(tcx, ty::TypingEnv::fully_monomorphized());
         assert!(fn_ty.is_fn());
         adjust_activity_to_abi(tcx, fn_ty, &mut input_activities);
         let symb = symbol_name_for_instance_in_crate(tcx, inst.clone(), LOCAL_CRATE);
 
         let mut new_target_attrs = target_attrs.clone();
         new_target_attrs.input_activity = input_activities;
-        let itm = new_target_attrs.into_item(symb, target_symbol);
+        let itm = new_target_attrs.into_item(symb, target_symbol, tcx.def_span(source_def_id));
         autodiff_items.push(itm);
     }