Question

我在Ubuntu上针对glib编译一个简单的示例程序时遇到了问题。我收到以下错误。我可以让它编译但不与-c标志链接，我相信这意味着我已经安装了glib标头，但它没有找到共享对象代码。另请参阅下面的Make文件。

$> make re
gcc -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include  -lglib-2.0       re.c   -o re
/tmp/ccxas1nI.o: In function `print_uppercase_words':
re.c:(.text+0x21): undefined reference to `g_regex_new'
re.c:(.text+0x41): undefined reference to `g_regex_match'
re.c:(.text+0x54): undefined reference to `g_match_info_fetch'
re.c:(.text+0x6e): undefined reference to `g_print'
re.c:(.text+0x7a): undefined reference to `g_free'
re.c:(.text+0x8b): undefined reference to `g_match_info_next'
re.c:(.text+0x97): undefined reference to `g_match_info_matches'
re.c:(.text+0xa7): undefined reference to `g_match_info_free'
re.c:(.text+0xb3): undefined reference to `g_regex_unref'
collect2: ld returned 1 exit status
make: *** [re] Error 1

Makefile使用了：

# Need to installed libglib2.0-dev some system specific install that will
# provide a value for pkg-config
INCLUDES=$(shell pkg-config --libs --cflags glib-2.0)
CC=gcc $(INCLUDES)
PROJECT=re

# Targets
full: clean compile

clean:
    rm $(PROJECT)

compile:
    $(CC) $(PROJECT).c -o $(PROJECT)

正在编译的

.c代码：

#include <glib.h>

void print_upppercase_words(const gchar *string)
{
  /* Print all uppercase-only words. */

  GRegex *regex;
  GMatchInfo *match_info;

  regex = g_regex_new("[A-Z]+", 0, 0, NULL);
  g_regex_match(regex, string, 0, &match_info);

  while (g_match_info_matches(match_info))
    {
      gchar *word = g_match_info_fetch(match_info, 0);
      g_print("Found %s\n", word);
      g_free(word);
      g_match_info_next(match_info, NULL);
    }

  g_match_info_free(match_info);
  g_regex_unref(regex);
}

int main()
{
  gchar *string = "My body is a cage.  My mind is THE key.";

  print_uppercase_words(string);
}

奇怪的是，当我运行glib-config时，它不喜欢那个命令，虽然我不知道怎么告诉Bash或者当它抱怨{{1}时如何使用一个而不是另一个在这两个包中。

gdlib-config

Answer 1

编译器命令末尾的库：

gcc -I / usr / include / glib-2.0 -I / usr / lib / x86_64-linux-gnu / glib-2.0 / include re.c -o re -lglib-2.0

来自GCC Link Options：

-llibrary
-l library
    Search the library named library when linking. 
    (The second alternative with the library as a separate argument
    is only for POSIX compliance and is not recommended.)

    It makes a difference where in the command you write this option;
    the linker searches and processes libraries and object files in the
    order they are specified.
    Thus, `foo.o -lz bar.o' searches library `z' after file foo.o but
    before bar.o. If bar.o refers to functions in `z', those functions
    may not be loaded.

Answer 2

gcc -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include re.c -o re -lglib-2.0

呃 - 地狱 - 我已经尝试了很多东西，可能会让它们有点不对劲，但我刚才尝试了上面的内容，它起作用了......太棒了。

编译glib时链接器错误...？

2 个答案: