Remove duplicate c-variadic.md

2 files changed, 5 insertions, 33 deletions

diff --git a/src/doc/unstable-book/src/library-features/c-variadic.md b/src/doc/unstable-book/src/library-features/c-variadic.md
deleted file mode 100644
index 77762116e6b..00000000000
--- a/src/doc/unstable-book/src/library-features/c-variadic.md
+++ /dev/null
@@ -1,26 +0,0 @@
-# `c_variadic`
-
-The tracking issue for this feature is: [#44930]
-
-[#44930]: https://github.com/rust-lang/rust/issues/44930
-
-------------------------
-
-The `c_variadic` library feature exposes the `VaList` structure,
-Rust's analogue of C's `va_list` type.
-
-## Examples
-
-```rust
-#![feature(c_variadic)]
-
-use std::ffi::VaList;
-
-pub unsafe extern "C" fn vadd(n: usize, mut args: VaList) -> usize {
-    let mut sum = 0;
-    for _ in 0..n {
-        sum += args.arg::<usize>();
-    }
-    sum
-}
-```
diff --git a/src/tools/tidy/src/unstable_book.rs b/src/tools/tidy/src/unstable_book.rs
index 8be25b98df0..d19de081807 100644
--- a/src/tools/tidy/src/unstable_book.rs
+++ b/src/tools/tidy/src/unstable_book.rs
@@ -93,14 +93,12 @@ pub fn check(path: &Path, features: CollectedFeatures, bad: &mut bool) {
     // Check for Unstable Book sections that don't have a corresponding unstable feature
     for feature_name in &unstable_book_lib_features_section_file_names - &unstable_lib_feature_names
     {
-        if !unstable_lang_feature_names.contains(&feature_name) {
-            tidy_error!(
-                bad,
-                "The Unstable Book has a 'library feature' section '{}' which doesn't \
+        tidy_error!(
+            bad,
+            "The Unstable Book has a 'library feature' section '{}' which doesn't \
                          correspond to an unstable library feature",
-                feature_name
-            );
-        }
+            feature_name
+        );
     }
 
     // Check for Unstable Book sections that don't have a corresponding unstable feature.