gcc在链接过程中，会链接很多库，包括动态库或者静态库。而这些库，包含了若干的.o文件，而在链接的过程中，不是每一个.o文件，都会链接到最终生成的文件中的。那么如何知道，库中的哪些.o文件，链接到最终生成的文件中呢？
通过查找资料，找到了gcc的链接选项，-Xlinker –verbose，就可以得到链接，所使用的库中的.o文件。
比如如下c文件：
#include <stdio.h>
#include <math.h>
int main() {
int k = -0;
unsigned j;
j = fabs(k);
printf("j=%x\n", j);
return 0;
}
一、动态库链接
使用如下命令编译：
gcc main.c -Xlinker --verbose
以下是输出信息：
|
attempt to open /usr/lib/../lib64/crt1.o succeeded /usr/lib/../lib64/crt1.o attempt to open /usr/lib/../lib64/crti.o succeeded /usr/lib/../lib64/crti.o attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtbegin.o succeeded /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtbegin.o attempt to open /tmp/ccSBhfuZ.o succeeded /tmp/ccSBhfuZ.o attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.a succeeded attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_s.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_s.a failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so succeeded opened script file /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so opened script file /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so attempt to open libgcc_s.so.1 failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_s.so.1 failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so.1 succeeded libgcc_s.so.1 (/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so.1) attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.a succeeded attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libc.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libc.a failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libc.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libc.a failed attempt to open /lib/../lib64/libc.so failed attempt to open /lib/../lib64/libc.a failed attempt to open /usr/lib/../lib64/libc.so succeeded opened script file /usr/lib/../lib64/libc.so opened script file /usr/lib/../lib64/libc.so attempt to open /lib64/libc.so.6 succeeded /lib64/libc.so.6 attempt to open /usr/lib64/libc_nonshared.a succeeded (/usr/lib64/libc_nonshared.a)elf-init.oS attempt to open /lib64/ld-linux-x86-64.so.2 succeeded /lib64/ld-linux-x86-64.so.2 attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.a succeeded attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_s.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_s.a failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so succeeded opened script file /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so opened script file /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so attempt to open libgcc_s.so.1 failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_s.so.1 failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so.1 succeeded libgcc_s.so.1 (/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgcc_s.so.1) attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.so failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.a succeeded attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtend.o succeeded /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtend.o attempt to open /usr/lib/../lib64/crtn.o succeeded /usr/lib/../lib64/crtn.o ld-linux-x86-64.so.2 needed by /lib64/libc.so.6 found ld-linux-x86-64.so.2 at /lib64/ld-linux-x86-64.so.2 |
从输出结果可以看到，链接动态库过程的详细信息，包括：
-
链接哪些库
-
链接库的位置
-
链接库是否成功
二、静态库链接
如果使用如下命令：
gcc main.c -static -Xlinker --verbose
以下是输出信息：
|
attempt to open /usr/lib/../lib64/crt1.o succeeded /usr/lib/../lib64/crt1.o attempt to open /usr/lib/../lib64/crti.o succeeded /usr/lib/../lib64/crti.o attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtbeginT.o succeeded /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtbeginT.o attempt to open /tmp/ccYjETs6.o succeeded /tmp/ccYjETs6.o attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc.a succeeded attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_eh.a succeeded attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libc.a failed attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libc.a failed attempt to open /lib/../lib64/libc.a failed attempt to open /usr/lib/../lib64/libc.a succeeded (/usr/lib/../lib64/libc.a)libc-start.o (/usr/lib/../lib64/libc.a)check_fds.o (/usr/lib/../lib64/libc.a)libc-tls.o (/usr/lib/../lib64/libc.a)elf-init.o (/usr/lib/../lib64/libc.a)errno.o (/usr/lib/../lib64/libc.a)bsd-_setjmp.o (/usr/lib/../lib64/libc.a)exit.o (/usr/lib/../lib64/libc.a)cxa_atexit.o (/usr/lib/../lib64/libc.a)printf.o (/usr/lib/../lib64/libc.a)libc_fatal.o (/usr/lib/../lib64/libc.a)stdio.o (/usr/lib/../lib64/libc.a)malloc.o (/usr/lib/../lib64/libc.a)morecore.o (/usr/lib/../lib64/libc.a)strlen.o (/usr/lib/../lib64/libc.a)memcmp.o (/usr/lib/../lib64/libc.a)memset.o (/usr/lib/../lib64/libc.a)mempcpy.o (/usr/lib/../lib64/libc.a)memcpy.o (/usr/lib/../lib64/libc.a)strchrnul.o (/usr/lib/../lib64/libc.a)memcmp-sse4.o (/usr/lib/../lib64/libc.a)memset-x86-64.o (/usr/lib/../lib64/libc.a)cacheinfo.o (/usr/lib/../lib64/libc.a)_exit.o (/usr/lib/../lib64/libc.a)environ.o (/usr/lib/../lib64/libc.a)exit-thread.o (/usr/lib/../lib64/libc.a)fxstat.o (/usr/lib/../lib64/libc.a)open.o (/usr/lib/../lib64/libc.a)read.o (/usr/lib/../lib64/libc.a)write.o (/usr/lib/../lib64/libc.a)fcntl.o (/usr/lib/../lib64/libc.a)sbrk.o (/usr/lib/../lib64/libc.a)getpagesize.o (/usr/lib/../lib64/libc.a)syslog.o (/usr/lib/../lib64/libc.a)mmap.o (/usr/lib/../lib64/libc.a)munmap.o (/usr/lib/../lib64/libc.a)mprotect.o (/usr/lib/../lib64/libc.a)madvise.o (/usr/lib/../lib64/libc.a)getsysstats.o (/usr/lib/../lib64/libc.a)init-misc.o (/usr/lib/../lib64/libc.a)mremap.o (/usr/lib/../lib64/libc.a)connect.o (/usr/lib/../lib64/libc.a)send.o (/usr/lib/../lib64/libc.a)socket.o (/usr/lib/../lib64/libc.a)have_sock_cloexec.o (/usr/lib/../lib64/libc.a)alloca_cutoff.o (/usr/lib/../lib64/libc.a)libc-lowlevellock.o (/usr/lib/../lib64/libc.a)libc-cancellation.o (/usr/lib/../lib64/libc.a)register-atfork.o (/usr/lib/../lib64/libc.a)libc_multiple_threads.o (/usr/lib/../lib64/libc.a)backtrace.o (/usr/lib/../lib64/libc.a)backtracesymsfd.o (/usr/lib/../lib64/libc.a)vfprintf_chk.o (/usr/lib/../lib64/libc.a)dl-support.o (/usr/lib/../lib64/libc.a)dl-addr.o (/usr/lib/../lib64/libc.a)enbl-secure.o (/usr/lib/../lib64/libc.a)dl-sysdep.o (/usr/lib/../lib64/libc.a)init-first.o (/usr/lib/../lib64/libc.a)sysdep.o (/usr/lib/../lib64/libc.a)init-arch.o (/usr/lib/../lib64/libc.a)lc-ctype.o (/usr/lib/../lib64/libc.a)xlocale.o (/usr/lib/../lib64/libc.a)global-locale.o (/usr/lib/../lib64/libc.a)ctype-info.o (/usr/lib/../lib64/libc.a)setfpucw.o (/usr/lib/../lib64/libc.a)fpu_control.o (/usr/lib/../lib64/libc.a)setjmp.o (/usr/lib/../lib64/libc.a)sigjmp.o (/usr/lib/../lib64/libc.a)sigprocmask.o (/usr/lib/../lib64/libc.a)abort.o (/usr/lib/../lib64/libc.a)bsearch.o (/usr/lib/../lib64/libc.a)getenv.o (/usr/lib/../lib64/libc.a)setenv.o (/usr/lib/../lib64/libc.a)secure-getenv.o (/usr/lib/../lib64/libc.a)strtol.o (/usr/lib/../lib64/libc.a)strtoul.o (/usr/lib/../lib64/libc.a)strtol_l.o (/usr/lib/../lib64/libc.a)strtoul_l.o (/usr/lib/../lib64/libc.a)grouping.o (/usr/lib/../lib64/libc.a)_itoa.o (/usr/lib/../lib64/libc.a)itoa-digits.o (/usr/lib/../lib64/libc.a)itoa-udigits.o (/usr/lib/../lib64/libc.a)vfprintf.o (/usr/lib/../lib64/libc.a)printf_fp.o (/usr/lib/../lib64/libc.a)reg-printf.o (/usr/lib/../lib64/libc.a)printf_fphex.o (/usr/lib/../lib64/libc.a)reg-type.o (/usr/lib/../lib64/libc.a)fprintf.o (/usr/lib/../lib64/libc.a)dprintf.o (/usr/lib/../lib64/libc.a)sscanf.o (/usr/lib/../lib64/libc.a)funlockfile.o (/usr/lib/../lib64/libc.a)printf-parsemb.o (/usr/lib/../lib64/libc.a)iofclose.o (/usr/lib/../lib64/libc.a)iofopen.o (/usr/lib/../lib64/libc.a)iofputs.o (/usr/lib/../lib64/libc.a)ioftell.o (/usr/lib/../lib64/libc.a)iofwrite.o (/usr/lib/../lib64/libc.a)iopadn.o (/usr/lib/../lib64/libc.a)ioseekoff.o (/usr/lib/../lib64/libc.a)iovsscanf.o (/usr/lib/../lib64/libc.a)iowpadn.o (/usr/lib/../lib64/libc.a)wgenops.o (/usr/lib/../lib64/libc.a)wfileops.o (/usr/lib/../lib64/libc.a)iofwide.o (/usr/lib/../lib64/libc.a)memstream.o (/usr/lib/../lib64/libc.a)iovdprintf.o (/usr/lib/../lib64/libc.a)fcloseall.o (/usr/lib/../lib64/libc.a)iofgets_u.o (/usr/lib/../lib64/libc.a)iofputs_u.o (/usr/lib/../lib64/libc.a)fileops.o (/usr/lib/../lib64/libc.a)genops.o (/usr/lib/../lib64/libc.a)stdfiles.o (/usr/lib/../lib64/libc.a)strops.o (/usr/lib/../lib64/libc.a)strchr.o (/usr/lib/../lib64/libc.a)strcmp.o (/usr/lib/../lib64/libc.a)_strerror.o (/usr/lib/../lib64/libc.a)strnlen.o (/usr/lib/../lib64/libc.a)strncmp.o (/usr/lib/../lib64/libc.a)strrchr.o (/usr/lib/../lib64/libc.a)memchr.o (/usr/lib/../lib64/libc.a)memmove.o (/usr/lib/../lib64/libc.a)wordcopy.o (/usr/lib/../lib64/libc.a)rawmemchr.o (/usr/lib/../lib64/libc.a)strcmp-ssse3.o (/usr/lib/../lib64/libc.a)strend-sse4.o (/usr/lib/../lib64/libc.a)strstr-c.o (/usr/lib/../lib64/libc.a)wmemcpy.o (/usr/lib/../lib64/libc.a)wmemmove.o (/usr/lib/../lib64/libc.a)wmemset.o (/usr/lib/../lib64/libc.a)wmempcpy.o (/usr/lib/../lib64/libc.a)wcrtomb.o (/usr/lib/../lib64/libc.a)wcsrtombs.o (/usr/lib/../lib64/libc.a)mbsnrtowcs.o (/usr/lib/../lib64/libc.a)wcsnlen.o (/usr/lib/../lib64/libc.a)wcsmbsload.o (/usr/lib/../lib64/libc.a)localtime.o (/usr/lib/../lib64/libc.a)time.o (/usr/lib/../lib64/libc.a)tzset.o (/usr/lib/../lib64/libc.a)tzfile.o (/usr/lib/../lib64/libc.a)strftime_l.o (/usr/lib/../lib64/libc.a)era.o (/usr/lib/../lib64/libc.a)alt_digit.o (/usr/lib/../lib64/libc.a)lc-time-cleanup.o (/usr/lib/../lib64/libc.a)opendir.o (/usr/lib/../lib64/libc.a)closedir.o (/usr/lib/../lib64/libc.a)readdir.o (/usr/lib/../lib64/libc.a)getdents.o (/usr/lib/../lib64/libc.a)uname.o (/usr/lib/../lib64/libc.a)fork.o (/usr/lib/../lib64/libc.a)getpid.o (/usr/lib/../lib64/libc.a)getuid.o (/usr/lib/../lib64/libc.a)geteuid.o (/usr/lib/../lib64/libc.a)getgid.o (/usr/lib/../lib64/libc.a)getegid.o (/usr/lib/../lib64/libc.a)sched_yield.o (/usr/lib/../lib64/libc.a)xstat.o (/usr/lib/../lib64/libc.a)close.o (/usr/lib/../lib64/libc.a)access.o (/usr/lib/../lib64/libc.a)have_o_cloexec.o (/usr/lib/../lib64/libc.a)brk.o (/usr/lib/../lib64/libc.a)writev.o (/usr/lib/../lib64/libc.a)tsearch.o (/usr/lib/../lib64/libc.a)llseek.o (/usr/lib/../lib64/libc.a)wctrans.o (/usr/lib/../lib64/libc.a)towctrans.o (/usr/lib/../lib64/libc.a)readonly-area.o (/usr/lib/../lib64/libc.a)dl-load.o (/usr/lib/../lib64/libc.a)dl-cache.o (/usr/lib/../lib64/libc.a)dl-lookup.o (/usr/lib/../lib64/libc.a)dl-object.o (/usr/lib/../lib64/libc.a)dl-reloc.o (/usr/lib/../lib64/libc.a)dl-error.o (/usr/lib/../lib64/libc.a)dl-debug.o (/usr/lib/../lib64/libc.a)dl-misc.o (/usr/lib/../lib64/libc.a)dl-tls.o (/usr/lib/../lib64/libc.a)dl-origin.o (/usr/lib/../lib64/libc.a)dl-scope.o (/usr/lib/../lib64/libc.a)dl-execstack.o (/usr/lib/../lib64/libc.a)dl-trampoline.o (/usr/lib/../lib64/libc.a)dl-profstub.o (/usr/lib/../lib64/libc.a)dl-tsd.o (/usr/lib/../lib64/libc.a)dl-tlsdesc.o (/usr/lib/../lib64/libc.a)gconv_db.o (/usr/lib/../lib64/libc.a)gconv_conf.o (/usr/lib/../lib64/libc.a)gconv_builtin.o (/usr/lib/../lib64/libc.a)gconv_simple.o (/usr/lib/../lib64/libc.a)gconv_trans.o (/usr/lib/../lib64/libc.a)gconv_cache.o (/usr/lib/../lib64/libc.a)gconv_dl.o (/usr/lib/../lib64/libc.a)setlocale.o (/usr/lib/../lib64/libc.a)findlocale.o (/usr/lib/../lib64/libc.a)loadlocale.o (/usr/lib/../lib64/libc.a)loadarchive.o (/usr/lib/../lib64/libc.a)lc-monetary.o (/usr/lib/../lib64/libc.a)lc-numeric.o (/usr/lib/../lib64/libc.a)C-ctype.o (/usr/lib/../lib64/libc.a)C-messages.o (/usr/lib/../lib64/libc.a)C-monetary.o (/usr/lib/../lib64/libc.a)C-numeric.o (/usr/lib/../lib64/libc.a)C-time.o (/usr/lib/../lib64/libc.a)C-paper.o (/usr/lib/../lib64/libc.a)C-name.o (/usr/lib/../lib64/libc.a)C-address.o (/usr/lib/../lib64/libc.a)C-telephone.o (/usr/lib/../lib64/libc.a)C-measurement.o (/usr/lib/../lib64/libc.a)C-identification.o (/usr/lib/../lib64/libc.a)C-collate.o (/usr/lib/../lib64/libc.a)SYS_libc.o (/usr/lib/../lib64/libc.a)C_name.o (/usr/lib/../lib64/libc.a)dcgettext.o (/usr/lib/../lib64/libc.a)dcigettext.o (/usr/lib/../lib64/libc.a)finddomain.o (/usr/lib/../lib64/libc.a)loadmsgcat.o (/usr/lib/../lib64/libc.a)localealias.o (/usr/lib/../lib64/libc.a)l10nflist.o (/usr/lib/../lib64/libc.a)explodename.o (/usr/lib/../lib64/libc.a)plural.o (/usr/lib/../lib64/libc.a)plural-exp.o (/usr/lib/../lib64/libc.a)hash-string.o (/usr/lib/../lib64/libc.a)s_isinf.o (/usr/lib/../lib64/libc.a)s_isnan.o (/usr/lib/../lib64/libc.a)s_isinfl.o (/usr/lib/../lib64/libc.a)s_isnanl.o (/usr/lib/../lib64/libc.a)__longjmp.o (/usr/lib/../lib64/libc.a)raise.o (/usr/lib/../lib64/libc.a)sigaction.o (/usr/lib/../lib64/libc.a)msort.o (/usr/lib/../lib64/libc.a)cmp.o (/usr/lib/../lib64/libc.a)divrem.o (/usr/lib/../lib64/libc.a)lshift.o (/usr/lib/../lib64/libc.a)rshift.o (/usr/lib/../lib64/libc.a)mul.o (/usr/lib/../lib64/libc.a)mul_1.o (/usr/lib/../lib64/libc.a)mul_n.o (/usr/lib/../lib64/libc.a)sub_n.o (/usr/lib/../lib64/libc.a)submul_1.o (/usr/lib/../lib64/libc.a)dbl2mpn.o (/usr/lib/../lib64/libc.a)ldbl2mpn.o (/usr/lib/../lib64/libc.a)fpioconst.o (/usr/lib/../lib64/libc.a)itowa-digits.o (/usr/lib/../lib64/libc.a)reg-modifier.o (/usr/lib/../lib64/libc.a)vfscanf.o (/usr/lib/../lib64/libc.a)errlist.o (/usr/lib/../lib64/libc.a)filedoalloc.o (/usr/lib/../lib64/libc.a)wfiledoalloc.o (/usr/lib/../lib64/libc.a)iogetdelim.o (/usr/lib/../lib64/libc.a)iogetline.o (/usr/lib/../lib64/libc.a)fileno.o (/usr/lib/../lib64/libc.a)fseek.o (/usr/lib/../lib64/libc.a)ftello.o (/usr/lib/../lib64/libc.a)iofread_u.o (/usr/lib/../lib64/libc.a)strcpy.o (/usr/lib/../lib64/libc.a)strdup.o (/usr/lib/../lib64/libc.a)strndup.o (/usr/lib/../lib64/libc.a)strstr.o (/usr/lib/../lib64/libc.a)stpcpy.o (/usr/lib/../lib64/libc.a)strcasecmp_l.o (/usr/lib/../lib64/libc.a)strsep.o (/usr/lib/../lib64/libc.a)memmem.o (/usr/lib/../lib64/libc.a)argz-count.o (/usr/lib/../lib64/libc.a)argz-ctsep.o (/usr/lib/../lib64/libc.a)argz-stringify.o (/usr/lib/../lib64/libc.a)argz-addsep.o (/usr/lib/../lib64/libc.a)strcasecmp_l-ssse3.o (/usr/lib/../lib64/libc.a)strcasecmp_l-nonascii.o (/usr/lib/../lib64/libc.a)wcschr.o (/usr/lib/../lib64/libc.a)wcslen.o (/usr/lib/../lib64/libc.a)mbrlen.o (/usr/lib/../lib64/libc.a)mbrtowc.o (/usr/lib/../lib64/libc.a)offtime.o (/usr/lib/../lib64/libc.a)mktime.o (/usr/lib/../lib64/libc.a)sysconf.o (/usr/lib/../lib64/libc.a)get_child_max.o (/usr/lib/../lib64/libc.a)getcwd.o (/usr/lib/../lib64/libc.a)isatty.o (/usr/lib/../lib64/libc.a)tcgetattr.o (/usr/lib/../lib64/libc.a)getrlimit.o (/usr/lib/../lib64/libc.a)getdtsz.o (/usr/lib/../lib64/libc.a)getclktck.o (/usr/lib/../lib64/libc.a)dl-runtime.o (/usr/lib/../lib64/libc.a)dl-profile.o (/usr/lib/../lib64/libc.a)dl-libc.o (/usr/lib/../lib64/libc.a)tlsdesc.o (/usr/lib/../lib64/libc.a)gconv_open.o (/usr/lib/../lib64/libc.a)gconv.o (/usr/lib/../lib64/libc.a)gconv_close.o (/usr/lib/../lib64/libc.a)localename.o (/usr/lib/../lib64/libc.a)qsort.o (/usr/lib/../lib64/libc.a)strtof.o (/usr/lib/../lib64/libc.a)strtod.o (/usr/lib/../lib64/libc.a)strtold.o (/usr/lib/../lib64/libc.a)strtof_l.o (/usr/lib/../lib64/libc.a)strtod_l.o (/usr/lib/../lib64/libc.a)strtold_l.o (/usr/lib/../lib64/libc.a)add_n.o (/usr/lib/../lib64/libc.a)addmul_1.o (/usr/lib/../lib64/libc.a)mpn2flt.o (/usr/lib/../lib64/libc.a)mpn2dbl.o (/usr/lib/../lib64/libc.a)mpn2ldbl.o (/usr/lib/../lib64/libc.a)tens_in_limb.o (/usr/lib/../lib64/libc.a)sdlerror.o (/usr/lib/../lib64/libc.a)sdladdr.o (/usr/lib/../lib64/libc.a)sdladdr1.o (/usr/lib/../lib64/libc.a)sdlinfo.o (/usr/lib/../lib64/libc.a)sdlmopen.o (/usr/lib/../lib64/libc.a)strerror.o (/usr/lib/../lib64/libc.a)strpbrk.o (/usr/lib/../lib64/libc.a)strncase_l.o (/usr/lib/../lib64/libc.a)strncase_l-ssse3.o (/usr/lib/../lib64/libc.a)strncase_l-nonascii.o (/usr/lib/../lib64/libc.a)profil.o (/usr/lib/../lib64/libc.a)prof-freq.o (/usr/lib/../lib64/libc.a)dl-open.o (/usr/lib/../lib64/libc.a)dl-close.o (/usr/lib/../lib64/libc.a)asprintf.o (/usr/lib/../lib64/libc.a)vasprintf.o (/usr/lib/../lib64/libc.a)sdlopen.o (/usr/lib/../lib64/libc.a)sdlclose.o (/usr/lib/../lib64/libc.a)sdlsym.o (/usr/lib/../lib64/libc.a)sdlvsym.o (/usr/lib/../lib64/libc.a)setitimer.o (/usr/lib/../lib64/libc.a)dl-deps.o (/usr/lib/../lib64/libc.a)dl-init.o (/usr/lib/../lib64/libc.a)dl-fini.o (/usr/lib/../lib64/libc.a)dl-version.o (/usr/lib/../lib64/libc.a)dl-sym.o (/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_eh.a)unwind-dw2.o (/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_eh.a)unwind-dw2-fde-dip.o (/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/libgcc_eh.a)unwind-c.o (/usr/lib/../lib64/libc.a)dl-iteratephdr.o attempt to open /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtend.o succeeded /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtend.o attempt to open /usr/lib/../lib64/crtn.o succeeded /usr/lib/../lib64/crtn.o |
从输出结果可以看到，链接动态库过程的详细信息，包括：
-
链接哪些库
-
链接库的位置
-
链接库是否成功
-
链接库中所使用的.o文件
从输出结果看出，即使一个简单的c程序，也会链接库中，非常多的.o文件。
三、总结
可以通过-Xlinker –verbose选项，来获取gcc链接过程中，使用的库以及.o信息。这样会帮忙理解链接过程。