UPDATE - accept start_point and snippet instead of SourceMap

compiler/rustc_attr/src/builtin.rs

@@ -67,7 +67,7 @@ fn handle_errors(sess: &ParseSess, span: Span, error: AttrError) {
                 span,
                 reason,
                 is_bytestr,
-                source_map: sess.source_map(),
+                start_point_span: sess.source_map().start_point(span),
             });
         }
     }

compiler/rustc_attr/src/session_diagnostics.rs

@@ -6,7 +6,7 @@ use rustc_errors::{
 };
 use rustc_macros::SessionDiagnostic;
 use rustc_session::SessionDiagnostic;
-use rustc_span::{source_map::SourceMap, Span, Symbol};
+use rustc_span::{Span, Symbol};
 
 use crate::UnsupportedLiteralReason;
 
@@ -202,14 +202,14 @@ pub(crate) struct InvalidReprHintNoValue {
 }
 
 // Error code: E0565
-pub(crate) struct UnsupportedLiteral<'a> {
+pub(crate) struct UnsupportedLiteral {
     pub span: Span,
     pub reason: UnsupportedLiteralReason,
     pub is_bytestr: bool,
-    pub source_map: &'a SourceMap,
+    pub start_point_span: Span,
 }
 
-impl<'a> SessionDiagnostic<'a> for UnsupportedLiteral<'a> {
+impl<'a> SessionDiagnostic<'a> for UnsupportedLiteral {
     fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
         let mut diag = handler.struct_span_err_with_code(
             self.span,
@@ -227,7 +227,7 @@ impl<'a> SessionDiagnostic<'a> for UnsupportedLiteral<'a> {
         );
         if self.is_bytestr {
             diag.span_suggestion(
-                self.source_map.start_point(self.span),
+                self.start_point_span,
                 fluent::attr::unsupported_literal_suggestion,
                 "",
                 Applicability::MaybeIncorrect,

compiler/rustc_typeck/src/astconv/errors.rs

@@ -29,7 +29,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         self.tcx().sess.emit_err(MissingTypeParams {
             span,
             def_span: self.tcx().def_span(def_id),
-            source_map: self.tcx().sess.source_map(),
+            span_snippet: self.tcx().sess.source_map().span_to_snippet(span).ok(),
             missing_type_params,
             empty_generic_args,
         });

compiler/rustc_typeck/src/errors.rs

@@ -3,7 +3,7 @@ use rustc_errors::{error_code, Applicability, DiagnosticBuilder, ErrorGuaranteed
 use rustc_macros::{LintDiagnostic, SessionDiagnostic, SessionSubdiagnostic};
 use rustc_middle::ty::Ty;
 use rustc_session::SessionDiagnostic;
-use rustc_span::{source_map::SourceMap, symbol::Ident, Span, Symbol};
+use rustc_span::{symbol::Ident, Span, Symbol};
 
 #[derive(SessionDiagnostic)]
 #[diag(typeck::field_multiply_specified_in_initializer, code = "E0062")]
@@ -241,16 +241,16 @@ pub struct UnconstrainedOpaqueType {
     pub name: Symbol,
 }
 
-pub struct MissingTypeParams<'a> {
+pub struct MissingTypeParams {
     pub span: Span,
     pub def_span: Span,
+    pub span_snippet: Option<String>,
     pub missing_type_params: Vec<Symbol>,
     pub empty_generic_args: bool,
-    pub source_map: &'a SourceMap,
 }
 
 // Manual implementation of `SessionDiagnostic` to be able to call `span_to_snippet`.
-impl<'a> SessionDiagnostic<'a> for MissingTypeParams<'a> {
+impl<'a> SessionDiagnostic<'a> for MissingTypeParams {
     fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, ErrorGuaranteed> {
         let mut err = handler.struct_span_err_with_code(
             self.span,
@@ -270,8 +270,8 @@ impl<'a> SessionDiagnostic<'a> for MissingTypeParams<'a> {
         err.span_label(self.def_span, rustc_errors::fluent::typeck::label);
 
         let mut suggested = false;
-        if let (Ok(snippet), true) = (
+        if let (Some(snippet), true) = (
-            self.source_map.span_to_snippet(self.span),
+            self.span_snippet,
             // Don't suggest setting the type params if there are some already: the order is
             // tricky to get right and the user will already know what the syntax is.
             self.empty_generic_args,