[gcc r14-8546] gccrs: Add a test regular variadic functions errors

[Arthur Cohen]

https://gcc.gnu.org/g:4f45c715b83b91fe3c5a326a3474c7cebeefc09f

commit r14-8546-g4f45c715b83b91fe3c5a326a3474c7cebeefc09f
Author: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
Date:   Mon Nov 20 11:37:12 2023 +0100

    gccrs: Add a test regular variadic functions errors
    
    Add a new regression test for the error message in regular function
    variadic errors during ast validation pass.
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/non_foreign_variadic_function.rs: New test.
    
    Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Diff:
---
 gcc/testsuite/rust/compile/non_foreign_variadic_function.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/gcc/testsuite/rust/compile/non_foreign_variadic_function.rs b/gcc/testsuite/rust/compile/non_foreign_variadic_function.rs
new file mode 100644
index 000000000000..2a4d3090a66b
--- /dev/null
+++ b/gcc/testsuite/rust/compile/non_foreign_variadic_function.rs
@@ -0,0 +1,4 @@
+pub fn toto(a: i32, ...) {}
+// { dg-error "only foreign or .unsafe extern .C.. functions may be C-variadic" "" { target *-*-* } .-1 }
+
+fn main() {}