diff --git a/compiler/rustc_ast_passes/src/feature_gate.rs b/compiler/rustc_ast_passes/src/feature_gate.rs
index a1bd2679137d6..17af78460059b 100644
--- a/compiler/rustc_ast_passes/src/feature_gate.rs
+++ b/compiler/rustc_ast_passes/src/feature_gate.rs
@@ -536,7 +536,6 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session, features: &Features) {
             }
         };
     }
-    gate_all!(c_str_literals, "`c\"..\"` literals are experimental");
     gate_all!(
         if_let_guard,
         "`if let` guards are experimental",
diff --git a/compiler/rustc_builtin_macros/src/concat_bytes.rs b/compiler/rustc_builtin_macros/src/concat_bytes.rs
index c4f5af384c1aa..f1b45330ba6d6 100644
--- a/compiler/rustc_builtin_macros/src/concat_bytes.rs
+++ b/compiler/rustc_builtin_macros/src/concat_bytes.rs
@@ -19,8 +19,8 @@ fn invalid_type_err(
     let snippet = cx.sess.source_map().span_to_snippet(span).ok();
     match ast::LitKind::from_token_lit(token_lit) {
         Ok(ast::LitKind::CStr(_, _)) => {
-            // FIXME(c_str_literals): should concatenation of C string literals
-            // include the null bytes in the end?
+            // Avoid ambiguity in handling of terminal `NUL` by refusing to
+            // concatenate C string literals as bytes.
             cx.emit_err(errors::ConcatCStrLit { span: span });
         }
         Ok(ast::LitKind::Char(_)) => {
diff --git a/compiler/rustc_feature/src/accepted.rs b/compiler/rustc_feature/src/accepted.rs
index f07022733d495..f6460d1c1b78d 100644
--- a/compiler/rustc_feature/src/accepted.rs
+++ b/compiler/rustc_feature/src/accepted.rs
@@ -77,6 +77,8 @@ declare_features! (
     (accepted, bindings_after_at, "1.56.0", Some(65490), None),
     /// Allows empty structs and enum variants with braces.
     (accepted, braced_empty_structs, "1.8.0", Some(29720), None),
+    /// Allows `c"foo"` literals.
+    (accepted, c_str_literals, "CURRENT_RUSTC_VERSION", Some(105723), None),
     /// Allows `#[cfg_attr(predicate, multiple, attributes, here)]`.
     (accepted, cfg_attr_multi, "1.33.0", Some(54881), None),
     /// Allows the use of `#[cfg(doctest)]`, set when rustdoc is collecting doctests.
diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs
index 72100863bb522..bd28f2fe1911c 100644
--- a/compiler/rustc_feature/src/unstable.rs
+++ b/compiler/rustc_feature/src/unstable.rs
@@ -346,8 +346,6 @@ declare_features! (
     (unstable, async_fn_track_caller, "1.73.0", Some(110011), None),
     /// Allows builtin # foo() syntax
     (unstable, builtin_syntax, "1.71.0", Some(110680), None),
-    /// Allows `c"foo"` literals.
-    (unstable, c_str_literals, "1.71.0", Some(105723), None),
     /// Treat `extern "C"` function as nounwind.
     (unstable, c_unwind, "1.52.0", Some(74990), None),
     /// Allows using C-variadics.
diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs
index a375a1d69cdea..eebd79a285d69 100644
--- a/compiler/rustc_parse/src/lexer/mod.rs
+++ b/compiler/rustc_parse/src/lexer/mod.rs
@@ -221,9 +221,6 @@ impl<'a> StringReader<'a> {
                 rustc_lexer::TokenKind::Literal { kind, suffix_start } => {
                     let suffix_start = start + BytePos(suffix_start);
                     let (kind, symbol) = self.cook_lexer_literal(start, suffix_start, kind);
-                    if let token::LitKind::CStr | token::LitKind::CStrRaw(_) = kind {
-                        self.sess.gated_spans.gate(sym::c_str_literals, self.mk_sp(start, self.pos));
-                    }
                     let suffix = if suffix_start < self.pos {
                         let string = self.str_from(suffix_start);
                         if string == "_" {
diff --git a/src/tools/clippy/tests/ui/needless_raw_string.fixed b/src/tools/clippy/tests/ui/needless_raw_string.fixed
index 4ea711fd67a14..1a9c601c462ba 100644
--- a/src/tools/clippy/tests/ui/needless_raw_string.fixed
+++ b/src/tools/clippy/tests/ui/needless_raw_string.fixed
@@ -1,6 +1,5 @@
 #![allow(clippy::needless_raw_string_hashes, clippy::no_effect, unused)]
 #![warn(clippy::needless_raw_strings)]
-#![feature(c_str_literals)]
 
 fn main() {
     "aaa";
diff --git a/src/tools/clippy/tests/ui/needless_raw_string.rs b/src/tools/clippy/tests/ui/needless_raw_string.rs
index b6239f9b1f031..1126ea5aa3033 100644
--- a/src/tools/clippy/tests/ui/needless_raw_string.rs
+++ b/src/tools/clippy/tests/ui/needless_raw_string.rs
@@ -1,6 +1,5 @@
 #![allow(clippy::needless_raw_string_hashes, clippy::no_effect, unused)]
 #![warn(clippy::needless_raw_strings)]
-#![feature(c_str_literals)]
 
 fn main() {
     r#"aaa"#;
diff --git a/src/tools/clippy/tests/ui/needless_raw_string_hashes.fixed b/src/tools/clippy/tests/ui/needless_raw_string_hashes.fixed
index c99c2f46532a3..b2ad657d6b29f 100644
--- a/src/tools/clippy/tests/ui/needless_raw_string_hashes.fixed
+++ b/src/tools/clippy/tests/ui/needless_raw_string_hashes.fixed
@@ -1,6 +1,5 @@
 #![allow(clippy::no_effect, unused)]
 #![warn(clippy::needless_raw_string_hashes)]
-#![feature(c_str_literals)]
 
 fn main() {
     r"\aaa";
diff --git a/src/tools/clippy/tests/ui/needless_raw_string_hashes.rs b/src/tools/clippy/tests/ui/needless_raw_string_hashes.rs
index dcc2af69f4e9c..54d8ed76d4751 100644
--- a/src/tools/clippy/tests/ui/needless_raw_string_hashes.rs
+++ b/src/tools/clippy/tests/ui/needless_raw_string_hashes.rs
@@ -1,6 +1,5 @@
 #![allow(clippy::no_effect, unused)]
 #![warn(clippy::needless_raw_string_hashes)]
-#![feature(c_str_literals)]
 
 fn main() {
     r#"\aaa"#;
diff --git a/tests/ui/proc-macro/literal-to-string.rs b/tests/ui/proc-macro/literal-to-string.rs
index 494d17cbeeaff..eb009036a9a83 100644
--- a/tests/ui/proc-macro/literal-to-string.rs
+++ b/tests/ui/proc-macro/literal-to-string.rs
@@ -1,6 +1,5 @@
 // check-pass
 // edition: 2021
-#![feature(c_str_literals)]
 
 // aux-build: print-tokens.rs
 extern crate print_tokens;
diff --git a/tests/ui/proc-macro/literal-to-string.stdout b/tests/ui/proc-macro/literal-to-string.stdout
index 7b27fcf798b12..ec6427545f45c 100644
--- a/tests/ui/proc-macro/literal-to-string.stdout
+++ b/tests/ui/proc-macro/literal-to-string.stdout
@@ -3,91 +3,91 @@ TokenStream [
         kind: Integer,
         symbol: "1",
         suffix: None,
-        span: #0 bytes(172..173),
+        span: #0 bytes(144..145),
     },
     Literal {
         kind: Integer,
         symbol: "17",
         suffix: Some("u8"),
-        span: #0 bytes(182..186),
+        span: #0 bytes(154..158),
     },
     Literal {
         kind: Float,
         symbol: "42.",
         suffix: None,
-        span: #0 bytes(195..198),
+        span: #0 bytes(167..170),
     },
     Literal {
         kind: Float,
         symbol: "3.14",
         suffix: Some("f32"),
-        span: #0 bytes(207..214),
+        span: #0 bytes(179..186),
     },
     Literal {
         kind: Byte,
         symbol: "a",
         suffix: None,
-        span: #0 bytes(223..227),
+        span: #0 bytes(195..199),
     },
     Literal {
         kind: Byte,
         symbol: "\xFF",
         suffix: None,
-        span: #0 bytes(236..243),
+        span: #0 bytes(208..215),
     },
     Literal {
         kind: Char,
         symbol: "c",
         suffix: None,
-        span: #0 bytes(252..255),
+        span: #0 bytes(224..227),
     },
     Literal {
         kind: Char,
         symbol: "\x32",
         suffix: None,
-        span: #0 bytes(264..270),
+        span: #0 bytes(236..242),
     },
     Literal {
         kind: Str,
         symbol: "\\"str\\"",
         suffix: None,
-        span: #0 bytes(279..288),
+        span: #0 bytes(251..260),
     },
     Literal {
         kind: StrRaw(1),
         symbol: "\"raw\" str",
         suffix: None,
-        span: #0 bytes(297..311),
+        span: #0 bytes(269..283),
     },
     Literal {
         kind: StrRaw(3),
         symbol: "very ##\"raw\"## str",
         suffix: None,
-        span: #0 bytes(320..347),
+        span: #0 bytes(292..319),
     },
     Literal {
         kind: ByteStr,
         symbol: "\\"byte\\" str",
         suffix: None,
-        span: #0 bytes(356..371),
+        span: #0 bytes(328..343),
     },
     Literal {
         kind: ByteStrRaw(1),
         symbol: "\"raw\" \"byte\" str",
         suffix: None,
-        span: #0 bytes(380..402),
+        span: #0 bytes(352..374),
     },
     Literal {
         kind: CStr,
         symbol: "\\"c\\" str",
         suffix: None,
-        span: #0 bytes(411..423),
+        span: #0 bytes(383..395),
     },
     Literal {
         kind: CStrRaw(1),
         symbol: "\"raw\" \"c\" str",
         suffix: None,
-        span: #0 bytes(432..451),
+        span: #0 bytes(404..423),
     },
 ]
 1
diff --git a/tests/ui/rfcs/rfc-3348-c-string-literals/basic.rs b/tests/ui/rfcs/rfc-3348-c-string-literals/basic.rs
index 5037396000bf0..5609dc51a67ed 100644
--- a/tests/ui/rfcs/rfc-3348-c-string-literals/basic.rs
+++ b/tests/ui/rfcs/rfc-3348-c-string-literals/basic.rs
@@ -1,8 +1,6 @@
 // run-pass
 // edition: 2021
 
-#![feature(c_str_literals)]
-
 fn main() {
     assert_eq!(b"test\0", c"test".to_bytes_with_nul());
 }
diff --git a/tests/ui/rfcs/rfc-3348-c-string-literals/gate.rs b/tests/ui/rfcs/rfc-3348-c-string-literals/gate.rs
deleted file mode 100644
index ddd6d9a25daad..0000000000000
--- a/tests/ui/rfcs/rfc-3348-c-string-literals/gate.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-// gate-test-c_str_literals
-// known-bug: #113333
-// edition: 2021
-
-macro_rules! m {
-    ($t:tt) => {}
-}
-
-fn main() {
-    c"foo";
-    // FIXME(c_str_literals): This should be ``c".."` literals are experimental`
-
-    m!(c"test");
-    // FIXME(c_str_literals): This should be ``c".."` literals are experimental`
-}
diff --git a/tests/ui/rfcs/rfc-3348-c-string-literals/gate.stderr b/tests/ui/rfcs/rfc-3348-c-string-literals/gate.stderr
deleted file mode 100644
index ea666e4330830..0000000000000
--- a/tests/ui/rfcs/rfc-3348-c-string-literals/gate.stderr
+++ /dev/null
@@ -1,21 +0,0 @@
-error[E0658]: `c".."` literals are experimental
-  --> $DIR/gate.rs:10:5
-   |
-LL |     c"foo";
-   |     ^^^^^^
-   |
-   = note: see issue #105723 <https://github.com/rust-lang/rust/issues/105723> for more information
-   = help: add `#![feature(c_str_literals)]` to the crate attributes to enable
-
-error[E0658]: `c".."` literals are experimental
-  --> $DIR/gate.rs:13:8
-   |
-LL |     m!(c"test");
-   |        ^^^^^^^
-   |
-   = note: see issue #105723 <https://github.com/rust-lang/rust/issues/105723> for more information
-   = help: add `#![feature(c_str_literals)]` to the crate attributes to enable
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0658`.
diff --git a/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.rs b/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.rs
index 369173e23184e..a7e36b2233ec5 100644
Binary files a/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.rs and b/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.rs differ
diff --git a/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.stderr b/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.stderr
index 82d9f9cb32091..ff9006f6f97f1 100644
Binary files a/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.stderr and b/tests/ui/rfcs/rfc-3348-c-string-literals/no-nuls.stderr differ
diff --git a/tests/ui/rfcs/rfc-3348-c-string-literals/non-ascii.rs b/tests/ui/rfcs/rfc-3348-c-string-literals/non-ascii.rs
index 380445d7a7fb9..8a5f514db7f61 100644
--- a/tests/ui/rfcs/rfc-3348-c-string-literals/non-ascii.rs
+++ b/tests/ui/rfcs/rfc-3348-c-string-literals/non-ascii.rs
@@ -1,8 +1,6 @@
 // run-pass
 // edition: 2021
 
-#![feature(c_str_literals)]
-
 fn main() {
     assert_eq!(
         c"\xEF\x80🦀\u{1F980}".to_bytes_with_nul(),