From 9dbf20ef27b56c0bff35366689861ebbe5dfb7e5 Mon Sep 17 00:00:00 2001
From: Ezra Shaw <ezrasure@outlook.com>
Date: Fri, 7 Apr 2023 08:54:13 +1200
Subject: [PATCH] fix: fix regression in #109203

---
 .../rustc_parse/src/parser/diagnostics.rs     |  4 ++--
 tests/ui/parser/issues/issue-110014.rs        |  3 +++
 tests/ui/parser/issues/issue-110014.stderr    | 19 +++++++++++++++++++
 3 files changed, 24 insertions(+), 2 deletions(-)
 create mode 100644 tests/ui/parser/issues/issue-110014.rs
 create mode 100644 tests/ui/parser/issues/issue-110014.stderr

diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs
index 5210b8fe69d6e..e03ce5d712056 100644
--- a/compiler/rustc_parse/src/parser/diagnostics.rs
+++ b/compiler/rustc_parse/src/parser/diagnostics.rs
@@ -423,11 +423,11 @@ impl<'a> Parser<'a> {
         if let token::Literal(Lit {
             kind: token::LitKind::Integer | token::LitKind::Float,
             symbol,
-            suffix,
+            suffix: Some(suffix), // no suffix makes it a valid literal
         }) = self.token.kind
             && rustc_ast::MetaItemLit::from_token(&self.token).is_none()
         {
-            Some((symbol.as_str().len(), suffix.unwrap()))
+            Some((symbol.as_str().len(), suffix))
         } else {
             None
         }
diff --git a/tests/ui/parser/issues/issue-110014.rs b/tests/ui/parser/issues/issue-110014.rs
new file mode 100644
index 0000000000000..69d8f402bb620
--- /dev/null
+++ b/tests/ui/parser/issues/issue-110014.rs
@@ -0,0 +1,3 @@
+fn`2222222222222222222222222222222222222222() {}
+//~^ ERROR unknown start of token: `
+//~^^ ERROR expected identifier, found `2222222222222222222222222222222222222222`
diff --git a/tests/ui/parser/issues/issue-110014.stderr b/tests/ui/parser/issues/issue-110014.stderr
new file mode 100644
index 0000000000000..7f1dd592e1238
--- /dev/null
+++ b/tests/ui/parser/issues/issue-110014.stderr
@@ -0,0 +1,19 @@
+error: unknown start of token: `
+  --> $DIR/issue-110014.rs:1:3
+   |
+LL | fn`2222222222222222222222222222222222222222() {}
+   |   ^
+   |
+help: Unicode character '`' (Grave Accent) looks like ''' (Single Quote), but it is not
+   |
+LL | fn'2222222222222222222222222222222222222222() {}
+   |   ~
+
+error: expected identifier, found `2222222222222222222222222222222222222222`
+  --> $DIR/issue-110014.rs:1:4
+   |
+LL | fn`2222222222222222222222222222222222222222() {}
+   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected identifier
+
+error: aborting due to 2 previous errors
+