GCC (MingW) + LD generate nearly empty executable. Why? - c++

Question

For a specific requirement, I need my binary to fall below 510bytes.
Doing the program in assembler, I get <100 bytes, while adding same code in C++, the resulting code is over 1K. Looking the resulting binary, mostly all ( + 90%) is full of 0x00 characters (Only a few characters at the beginning and end are really populated).
Currently building commands:
gcc -Wall -Os -s -Wl,--stack,32 -nostdinc -nostdinc++ -fno-ident -fno-builtin -I. -c -o cppFile.coff cppFile.cpp
nasm -f elf -o main.elf main.asm
ld -T link.ld -o out.elf main.elf cppFile.coff
objcopy -O binary out.elf out.bin
Size of files generated:
cppFile.coff = 684 bytes
main.elf = 640
out.elf = 2707
out.bin = 1112
When not linking to the cppFile.coff (with only one empty function)
out.elf = 1984
out.bin = 31 (tested and working)
Why GCC or LD add so many nul charactres?
How to remove this empty space?
ENTRY(start)
phys = 0x7c00;
HEAP_SIZE = 0;
SECTIONS
{
.text phys : AT(phys) {
code = .;
*(.text)
*(.rodata)
}
.data : AT(phys + (data - code))
{
data = .;
*(.data)
}
.bss : AT(phys + (bss - code))
{
bss = .;
*(.bss)
}
end = .;
}