Rollup merge of #63459 - eddyb:issue-63430, r=petrochenkov

syntax: account for CVarArgs being in the argument list.

Fixes #63430 by testing for `1` argument (the `CVarArgs` itself) instead of `0`.

Note that the error has basically been impossible to trigger since the change that caused #63430, so perhaps we need an audit of untested errors.

Also, this check probably belongs in AST validation/HIR lowering, but I'd rather fix it in place for now.

r? @petrochenkov cc @dlrobertson

1 files changed, 1 insertions, 1 deletions

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 1c1428c5713..2286e74e633 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -1236,7 +1236,7 @@ impl<'a> Parser<'a> {
 
         let args: Vec<_> = args.into_iter().filter_map(|x| x).collect();
 
-        if c_variadic && args.is_empty() {
+        if c_variadic && args.len() <= 1 {
             self.span_err(sp,
                           "C-variadic function must be declared with at least one named argument");
         }