specify that extern c-variadic functions cannot be safe

folkertdev · ehuss · commit 5d90855b216f · 2025-06-03T14:41:39.000-07:00
diff --git a/src/items/external-blocks.md b/src/items/external-blocks.md
@@ -182,6 +182,9 @@ unsafe extern "C" {
 }
 ```
 
+r[items.extern.variadic.safety]
+A variadic extern function cannot be qualified as `safe`. Passing an unexpected number of arguments or arguments of an unexpected type to a variadic function is [undefined behavior][undefined].
+
 r[items.extern.attributes]
 ## Attributes on extern blocks
 

Original file line number	Diff line number	Diff line change
`@@ -182,6 +182,9 @@ unsafe extern "C" {`
`182`	`182`	`}`
`183`	`183`	```
`184`	`184`
	`185`	`+r[items.extern.variadic.safety]`
	`186`	+A variadic extern function cannot be qualified as `safe`. Passing an unexpected number of arguments or arguments of an unexpected type to a variadic function is [undefined behavior][undefined].
	`187`	`+`
`185`	`188`	`r[items.extern.attributes]`
`186`	`189`	`## Attributes on extern blocks`
`187`	`190`