C程序中对'printf'的未定义引用

Question

我试图理解一些gcc功能，如__attribute__，更确切地说，如何使用__attribute__((__section__("foo")))在特定的内存位置分配数据/代码。

我的设置

align.c

#include <stdio.h>
//Align some ints
#define BYTES 16
#define __weird_thing __attribute__((__section__("weird.data")))
int __weird_thing *bootstrap;
int a __attribute__((aligned(BYTES))) = 1;
int b __attribute__((aligned(BYTES))) = 2;
int c = 3;
int d __attribute__((aligned(BYTES))) = 4;


int main( int argc, char *argv[])
{
        extern a, b, c, d;
        int *p = &a;
        printf(" a = %p 
", &a);
        printf(" sizof(a) = %d
", sizeof(a));
        printf("__alignof__ = %d
", __alignof__(a));
        printf(" p = %p 

", p);

        printf(" b = %p 
", &b);
        printf(" sizof(b) = %d
", sizeof(b));
        printf("__alignof__ = %d
", __alignof__(b));
        p = p + (BYTES / sizeof(int));
        printf(" p = %p 

", p);

        printf(" c = %p 
", &c);
        printf(" sizof(c) = %d
", sizeof(c));
        printf("__alignof__ = %d
", __alignof__(c));
        p = p + sizeof(b) / sizeof(int) ;
        printf(" p = %p 

", p);

        long unsigned int alignment;
        for(;(alignment=( (long unsigned int) p) & (BYTES << 1 )- 1 ,    printf("alignment = %p
",alignment), alignment  != 0 ) ; p++);
        printf(" d = %p 
", &d);
        printf(" sizof(d) = %d
", sizeof(d));
        printf("__alignof__ = %d
", __alignof__(d));
        printf(" p = %p 

", p);
}

include/imposible.h

int imposible(void);

imposible.c

#include<imposible.h>
extern unsigned long int base;
int imposible(void)
{
        base++;
        return (int) &base;
}

ld.lds

SECTIONS
{
        . = 0x10000;
        weird.data : { *(weird.data) }
        base = .;
}

Problem

每当我尝试链接时，它都会因未定义的引用而失败

dudarev@Test-Sandbox section $ gcc -c align.c -o align.o
dudarev@Test-Sandbox section $ gcc -c -I include/ imposible.c -o imposible.o
imposible.c: In function ‘imposible’:
imposible.c:6:9: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
  return (int) &base;
     ^

dudarev@Test-Sandbox section $ ld -T ld.lds align.o imposible.o -o a.out
align.o: In function `main':
align.c:(.text+0x27): undefined reference to `printf'
align.c:(.text+0x3b): undefined reference to `printf'
align.c:(.text+0x4f): undefined reference to `printf'
align.c:(.text+0x65): undefined reference to `printf'
align.c:(.text+0x79): undefined reference to `printf'
align.o:align.c:(.text+0x8d): more undefined references to `printf' follow

由于我不准，它没有找到printf，这意味着stdio没有联系。我在glibc-static stackoverflow问题之后安装了this并尝试使用-lc切换ld

dudarev@Test-Sandbox section $ ld -lc -T ld.lds align.o imposible.o -o a.out
ld: cannot find -lc

我错过了什么人？

提前致谢