cURL 特定的未定义引用

Question

我终于能够正确（我认为）将 cURL 链接到代码块（GNU 编译器），并对所有 dll 问题进行排序。它能够编译并正确运行一次，然后停止处理与 libcurl.a(url.o) 相关的新错误。这两个错误是

undefined reference to 'idna_to_ascii_lz' 
undefined reference to 'string_prep_locale_charset'.  

这些错误是在之前成功构建之后出现的，这对我来说没有意义，因为我所做的修改很少。 我的构建选项是 -lcurl --lws2_32 和 -lwsock32（以消除编译成功后弹出的另一个错误）。

我认为我的链接是成功的，因为之前的构建成功，我添加了它之前要求的所有 dll。我该如何修复它，为什么它之前构建得很好？我应该打开编译器设置吗？唯一的一个是 -Wall 和 -fexceptions

测试代码如下，直接取自另一个网站，稍作修改。

#define CURL_STATICLIB
#include <stdio.h>
#include <curl/curl.h>
#include <curl/types.h>
#include <curl/easy.h>
#include <string>
#include <iostream>

size_t write_data(void *ptr, size_t size, size_t nmemb, FILE *stream) {
    size_t written;
    written = fwrite(ptr, size, nmemb, stream);
    return written;
}

int main(void) {
    CURL *curl;
    FILE *fp;
    CURLcode res;
    std::cout << "Hello World";
    char *url = "http://cnn.com";
    char outfilename[FILENAME_MAX] = "C:\\bbb.txt";
    curl = curl_easy_init();
    if (curl) {
        fp = fopen(outfilename,"wb");
        curl_easy_setopt(curl, CURLOPT_URL, url);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);
        res = curl_easy_perform(curl);
        curl_easy_cleanup(curl);
        fclose(fp);
    }
    return 0;
}

感谢大家的帮助

更新：根据 TimRau 的建议，我将 -lidn 添加到链接器选项中。我现在收到以下错误：

||=== Build: Debug in Curl2 (compiler: GNU GCC Compiler) ===|

C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ssluse.o)|| undefined reference to `ERR_remove_thread_state'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_err2stringA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_set_optionA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_simple_bind_sA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_search_sA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_err2stringA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_err2stringA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_set_optionA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_initA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_get_dnA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_first_attributeA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_get_values_lenA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_memfreeA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_next_attributeA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_memfreeA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_memfreeA'|
C:\libs\curl-7.34.0-devel-mingw32\lib\libcurl.a(ldap.o)|| undefined reference to `_imp__ldap_memfreeA'|
||=== Build failed: 17 error(s), 0 warning(s) (0 minute(s), 0 second(s)) ===|

对于链接库，我有以下链接： c:\libs\libcurl_imp.lib c:\libs\libeay32.lib c:\libs\openldap.lib c:\libs\ssleay32.lib

我的链接器搜索目录中还有 curl 库，并且 curl 包含编译器搜索目录。我按照http://www.learncpp.com/cpp-tutorial/a3-using-libraries-with-codeblocks/ 网上的说明将它们放入 因为它构建和工作一次，我认为这些设置是正确的，但我对这部分编程的理解有限。

更新 2：通过添加消除第一个错误

Answer 1

需要在编译命令的最后加上-lidn -lwldap32。