vararg stdarg with 64 bit values

I'm having trouble passing 'long long' or 'double' through a vararg function on a 32-bit ARM system raw hardware build.
Not only is the value wrong, but also following arg values.
Current downloaded binary build of the compiler 6.3.1
-march=armv7-a -mtune=cortex-a8 -mfpu=neon -ftree-vectorize -ffast-math -mfloat-abi=softfp -mcpu=cortex-a8

Can anyone verify it works for them?

e.g.
#include <stdarg.h>

long vartest(char *foo, ...) {
  long long x;
  long y;
  va_list va;
  va_start(va, foo);
  x = va_arg(va, long long);
  y = va_arg(va, long);
  va_end(va);
  return y;
}

int test() {
  long long x = 0x300000002;
  long y = 0x7;
  long r = vartest("foo",x,y); //r will be incorrect
  return r;
}