$ cat output-block.c
int flush_output(void)
{
    return add_block();
}

$ gcc -O3 -S output-block.c
$ cat output-block.s
        .file   "output-block.c"
        .text
        .p2align 4,,15
.globl flush_output
        .type   flush_output, @function
flush_output:
        pushl   %ebp
        movl    %esp, %ebp
        popl    %ebp
        jmp     add_block
        .size   flush_output, .-flush_output
        .ident  "GCC: (GNU) 4.1.0 20050315 (experimental)"
        .section        .note.GNU-stack,"",@progbits

The operations on ebp aren't necessary.