ref: 4dba5596398fe88df1210f15d0a1ccb68604c2da
dir: /tests/execute/0146-ifdef.c/
#define FOO #ifdef FOO int a; int b; #undef FOO #ifndef FOO int c; int d; #else int e; int f; #endif int e; int f; #ifdef FOO int c_; int d_; #else int e_; int f_; #endif int e_; int f_; int main() { return 0; } #else int j; int k; #ifdef FOO int j; int k; #else int n; int o; #endif int n; int o; #ifndef FOO int r; int s; #else int t; int u; #endif int t; int u; #error bad branch #endif