Controlling the order of static objects' constructor

Question

I'm writing a tiny kernel with c++11 and have two instances with the same type which have to be constructed before any other static objects are created.

The code I wrote is as follows:

// test.hpp
class test {
  // blahblah...
};

// test.cpp
typedef char fake_inst[sizeof(test)] __attribute__((aligned(alignof(test))));

fake_inst inst1;
fake_inst inst2;

// main.cpp
extern test inst1;
extern test inst2;

int kmain() {
    // copy data section

    // initialize bss section

    new (&inst1) test();
    new (&inst2) test();

    // call constructors in .init_array

    // kernel stuffs
}

It builds and works as expected without no warning messages, but not with LTO.

I get tons of warning messages complaining the type matching and I wonder if there's a workaround since it confuses me to find the other 'real' warning or error messages.

Any suggestion?

Answer 1

Could you use GCC's init_priority attribute?

Some_Class  A  __attribute__ ((init_priority (2000)));
Some_Class  B  __attribute__ ((init_priority (543)));

http://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Attributes.html#C_002b_002b-Attributes