// Simple message structures
typedef struct { int a; } MsgA;
typedef struct { int b; } MsgB;
typedef struct { int c; } MsgC;
typedef struct { int d; } MsgD;
typedef struct { int e; } MsgE;
typedef struct { int f; } MsgF;

// X-Macro for list elements: X(name,MsgName)
#define MY_LIST1 \
X(aaa, MsgA)\
X(bbb, MsgB)\
X(ccc, MsgC)\

// X-Macro for list elements: X(name,MsgName)
#define MY_LIST2 \
X(ddd, MsgD)\
X(eee, MsgE)\
X(fff, MsgF)\

// Generate structure of all messages
#define X(name,MsgName) MsgName name;
static struct { MY_LIST1 MY_LIST2 } list1_ = {0};
#undef X

// Generate structure of all messages
#define X(name,MsgName) struct { MsgName msg; } name;
static struct { MY_LIST1 MY_LIST2 } list2_ = {0};
#undef X

// Generate structure of all messages
#define X(name,MsgName) struct { MsgName msg; } list3_##name;
MY_LIST1 MY_LIST2
#undef X

static void test() {
    list1_.aaa.a; list1_.ddd.d;
    list1_.bbb.b; list1_.eee.e;
    list1_.ccc.c; list1_.fff.f;
    list2_.aaa.msg.a; list2_.ddd.msg.d;
    list2_.bbb.msg.b; list2_.eee.msg.e;
    list2_.ccc.msg.c; list2_.fff.msg.f;
    list3_aaa.msg.a; list3_ddd.msg.d;
    list3_bbb.msg.b; list3_eee.msg.e;
    list3_ccc.msg.c; list3_fff.msg.f;
}