1 // RUN: %clang_cc1 -E %s | FileCheck %s
2 #define hash_hash # ## #
3 #define mkstr(a) # a
4 #define in_between(a) mkstr(a)
5 #define join(c, d) in_between(c hash_hash d)
6 // CHECK: "x ## y";
7 join(x, y);
8 
9 #define FOO(x) A x B
10 // CHECK: A ## B;
11 FOO(##);
12