building these 2 files to a library:

//////////////////////////////////
module lib18456;
__gshared int initVar;

pragma(crt_constructor)
extern(C) void mir_cpuid_crt_init()
{
    initVar = 42;
}

/////////////////////////////////
module test18456b;

class ManualGC {
    void enable() {}
    void disable() {}
}

with "dmd -m64 -oftest.a -lib test18456b.d test18456.d"

produces a corrupt library that when linked with

/////////////////////////////////
import lib18456;

void main()
{
    assert(initVar == 42);
}

via via "dmd -m64 test18456.d test.a" produces:

/usr/bin/ld: error: test.a(lib18456.o): size of section .ctors is not multiple of address size
/usr/bin/ld: final link failed: Bad value

As the root corruption is not limited to use of pragma(crt_constructor), but just goes unnoticed otherwise, I've raised severity to "critical".