ODR Violation error

output.txt

g++ (Ubuntu 5.4.0-6ubuntu1~16.04.10) 5.4.0 20160609
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

test.h:8:3: warning: type ‘struct test2_t’ violates one definition rule [-Wodr]
 } test2_t;
   ^
test.h:8:3: note: a different type is defined in another translation unit
 } test2_t;
   ^
test.h:6:23: note: the first difference of corresponding definitions is field ‘t’
  std::vector<test1_t> t;
                       ^
test.h:6:23: note: a field of same name but different type is defined in another translation unit
  std::vector<test1_t> t;
                       ^
/usr/include/c++/5/bits/stl_vector.h:214:11: note: type ‘struct vector’ defined in anonymous namespace can not match type ‘struct vector’
     class vector : protected _Vector_base<_Tp, _Alloc>
           ^
/usr/include/c++/5/bits/stl_vector.h:214:11: note: the incompatible type defined in anonymous namespace in another translation unit
     class vector : protected _Vector_base<_Tp, _Alloc>
           ^

test.sh

mkdir test && cd test
cat > main.cpp <<EOF
#include "test.h"
int main() {
	test2_t t;
	t.test();
}
EOF
cat > test.cpp <<EOF
#include "test.h"
void test2_t::test() {}
EOF
cat > test.h << EOF
#pragma once
#include <vector>
typedef struct {
	typedef struct {
	} test1_t;
	std::vector<test1_t> t;
	void test();
} test2_t;
EOF
g++ --version
g++ -flto -c -o test.o test.cpp -std=c++11
g++ -flto -c -o main.o main.cpp -std=c++11
g++ -flto *.o -o test
cd ..