llvm-project/clang/test/Parser/traditional_arg_scope.c

// RUN: %clang_cc1 -fsyntax-only %s -verify

int x(a) int a; {return a;}
int y(b) int b; {return a;} // expected-error {{use of undeclared identifier}}

// PR2332
int a(a)int a;{a=10;return a;}