And it takes effort to simplify things.

>Free Pascal
how good is it? Probably doesn't support SEH?

push byte 0xXX
pop reg    

boo@DESKTOP-1V5DHQJ:/mnt/c/Users/BOO/Projects$ gcc h.c -nodefaultlibs -o h
/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/11/../../../x86_64-linux-gnu/Scrt1.o: in function `_start':
(.text+0x21): undefined reference to `__libc_start_main'
/usr/bin/ld: /tmp/ccXIhnbE.o: in function `main':
h.c.text+0x18): undefined reference to `printf'
collect2: error: ld returned 1 exit status
boo@DESKTOP-1V5DHQJ:/mnt/c/Users/BOO/Projects$ gcc h.c -nostdlib -o h
/usr/bin/ld: warning: cannot find entry symbol _start; defaulting to 0000000000001030
/usr/bin/ld: /tmp/ccAjJnQW.o: in function `main':
h.c.text+0x18): undefined reference to `printf'
collect2: error: ld returned 1 exit status
boo@DESKTOP-1V5DHQJ:/mnt/c/Users/BOO/Projects$    

printf is part of the stdlib.

If you want no stdlib then you have to avoid printf. You'll need to use the system calls directly.

//bin/true '
/*'

NAME="${0%.*}"
gcc -nostdlib -m32 -DBITS=32 -x c -masm=intel -o "$NAME" "${0}" || exit $?

exit 0

*/

#include <unistd.h>             // STDOUT_FILENO
#include <sys/syscall.h>        // SYS_write, SYS_exit
#define S_(v) #v
#define S(v) S_(v)              // convert macro into literal string

const char text[] = "Hello from "S(BITS)"-bit world!\n";

int main() {
        asm (
        "       _start:                         \n"
        "       mov     eax, "S(SYS_write)"     \n"
        "       mov     ebx, "S(STDOUT_FILENO)" \n"
        "       lea     ecx, [%[str]]           \n"
        "       mov     edx, %[len]             \n"
        "       int     0x80                    \n"
        "       mov     eax, "S(SYS_exit)"      \n"
        "       xor     ebx, ebx                \n"
        "       int     0x80                    \n"
        :
        :
        [str]   "m" (text),
        [len]   "i" (sizeof (text)-1)
        );
}    

printf is part of the stdlib.

If you want no stdlib then you have to avoid printf. You'll need to use the system calls directly.

-ffunction-sections -fdata-sections -fno-strict-aliasing    

From what I can find you can use these settings in GCC to enable a build to exclude unused functions.

Code:

-ffunction-sections -fdata-sections -fno-strict-aliasing    

I gues one can put these in the Makefile or build script when creating the libraries and executables.

Other compilers probably have similar options or settings.

Note that this often prohibits more fine tuned optimisations, so using settings like these might not always be beneficial. As with everything, test it before committing to using it.

So, the library has to be 'built' with the feature to use functions separately.