Question

我通过将C ++代码与标准库C ++库链接而收到LNK2019错误。我需要知道哪些库包含功能：

is_c_termination_complete，
__acrt_initialize，
__acrt_uninitialize，
__acrt_uninitialize_critical，
__acrt_thread_attach，
__acrt_thread_detach

将其包含在链接过程中。

我正在用MS Visual Studio社区2017和Intel Parallel Studio xe 2019 update 1用C ++编写代码，这些代码将集成到第三方软件中。第三方软件提供了一个“ make”选项来编译目标文件并将它们链接在一起。

编译正常，链接提供了一个问题。

第三方软件提供了一个条目，以变量的形式提供基本的链接器选项。默认选项如下：

link_sl='LINK', '/nologo', '/NOENTRY', '/INCREMENTAL:NO', '/subsystem:console', '/machine:AMD64', 
' /NODEFAULTLIB:LIBC.LIB', '/NODEFAULTLIB:LIBCMT.LIB','/DEFAULTLIB:OLDNAMES.LIB', '/DEFAULTLIB:LIBIFCOREMD.LIB', '/DEFAULTLIB:LIBIFPORTMD.LIB', '/DEFAULTLIB:LIBMMD.LIB', '/DEFAULTLIB:kernel32.lib', '/DEFAULTLIB:user32.lib', '/DEFAULTLIB:advapi32.lib','/FIXED:NO', '/dll','/def:%E', '/out:%U', '%F', '%A', '%L', '%B', 
'oldnames.lib', 'user32.lib', 'ws2_32.lib', 'netapi32.lib','advapi32.lib', 
'msvcrt.lib', 'vcruntime.lib', 'ucrt.lib']

链接时出现以下11个错误：

msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __vcrt_initialize referenced in function __scrt_initialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __vcrt_uninitialize referenced in function __scrt_initialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __vcrt_uninitialize_critical referenced in function __scrt_dllmain_uninitialize_critical
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __vcrt_thread_attach referenced in function __scrt_dllmain_crt_thread_attach
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __vcrt_thread_detach referenced in function __scrt_dllmain_crt_thread_attach
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol _is_c_termination_complete referenced in function __scrt_dllmain_uninitialize_c
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_initialize referenced in function __scrt_initialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_uninitialize referenced in function __scrt_uninitialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_uninitialize_critical referenced in function __scrt_dllmain_uninitialize_critical
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_thread_attach referenced in function __scrt_dllmain_crt_thread_attach
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_thread_detach referenced in function __scrt_dllmain_crt_thread_detach

这基本上意味着我没有包括所有必需的库。我已经发现，在选项中包含库'libvcruntime.lib'可以将错误减少到6个。因此，使用：

link_sl='LINK', '/nologo', '/NOENTRY', '/INCREMENTAL:NO', '/subsystem:console', '/machine:AMD64', 
' /NODEFAULTLIB:LIBC.LIB', '/NODEFAULTLIB:LIBCMT.LIB','/DEFAULTLIB:OLDNAMES.LIB', '/DEFAULTLIB:LIBIFCOREMD.LIB', '/DEFAULTLIB:LIBIFPORTMD.LIB', '/DEFAULTLIB:LIBMMD.LIB', '/DEFAULTLIB:kernel32.lib', '/DEFAULTLIB:user32.lib', '/DEFAULTLIB:advapi32.lib','/FIXED:NO', '/dll','/def:%E', '/out:%U', '%F', '%A', '%L', '%B', 
'oldnames.lib', 'user32.lib', 'ws2_32.lib', 'netapi32.lib','advapi32.lib', 
'msvcrt.lib', 'vcruntime.lib', 'ucrt.lib',**'libvcruntime.lib'**]

结果：

msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol _is_c_termination_complete referenced in function __scrt_dllmain_uninitialize_c
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_initialize referenced in function __scrt_initialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_uninitialize referenced in function __scrt_uninitialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_uninitialize_critical referenced in function __scrt_dllmain_uninitialize_critical
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_thread_attach referenced in function __scrt_dllmain_crt_thread_attach
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_thread_detach referenced in function __scrt_dllmain_crt_thread_detach

我还需要在链接过程中包括哪些其他库来解决这些问题？

Answer 1

我们遇到了完全相同的问题。通过在Visual Studio中创建一个简单的控制台项目，我们发现以下代码：

#include <stdio.h>
extern "C" {
    int _is_c_termination_complete(...);
    int __acrt_initialize(...);
    int __acrt_uninitialize(...);
}


int main()
{
    if(_is_c_termination_complete())
    { 
        __acrt_initialize();
    }
    fprintf(stdout, "Hello world\n");
    return 0;
}

在拆卸时将其终止。

main:
<snip>
00007FF68B44194A  call        __scrt_stub_for_is_c_termination_complete (07FF68B441140h)  
00007FF68B44194F  test        eax,eax  
00007FF68B441951  je          main+38h (07FF68B441958h)  
00007FF68B441953  call        __acrt_initialize (07FF68B441393h)  
00007FF68B441958  mov         ecx,1  
00007FF68B44195D  call        qword ptr [__imp___acrt_iob_func (07FF68B4502F0h)]  
00007FF68B441963  lea         rdx,[string "Hello world\n" (07FF68B449C28h)]  
00007FF68B44196A  mov         rcx,rax  
00007FF68B44196D  call        fprintf (07FF68B44119Ah)  
00007FF68B441972  xor         eax,eax  
00007FF68B441974  lea         rsp,[rbp+0C8h]  
00007FF68B44197B  pop         rdi  
00007FF68B44197C  pop         rbp

链接器显然将_is_c_termination_complete重写为__scrt_stub_for_is_c_termination_complete。据我们所知，函数_is_c_termination_complete在任何特定crt中都不存在。不同的crt似乎有不同的实现方式，链接器似乎会根据您要链接的crt重写这些实现。

对于我们来说，从链接行中删除/ NOENTRY选项可修复6个错误。显然，/ NOENTRY阻止了链接器提取crt的实现。

显然，/ NOENTRY实际上意味着没有代码，我们肯定有。

https://docs.microsoft.com/en-us/cpp/build/reference/noentry-no-entry-point?view=vs-2019

Answer 2

在此第三方软件提供的框架内工作时，我遇到了完全相同的问题。尽管我无法直接回答查找包含_is_c_termination_complete的库的问题，但我意识到仍然可以使您的代码正常工作：只需在/FORCE标志列表中添加一个link_sl标志。 / p>

根据MSVC official documentation：

/ FORCE选项告诉链接器创建有效的.exe文件或DLL，即使已引用但未定义符号或已将符号多重定义的情况。

因此，LNK2019错误消息将不会阻止链接程序生成dll库，这对于运行第三方软件至关重要。链接器消息如下所示：

msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol _is_c_termination_complete referenced in function __scrt_dllmain_uninitialize_c
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_initialize referenced in function __scrt_initialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_uninitialize referenced in function __scrt_uninitialize_crt
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_uninitialize_critical referenced in function __scrt_dllmain_uninitialize_critical
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_thread_attach referenced in function __scrt_dllmain_crt_thread_attach
msvcrt.lib(utility.obj) : error LNK2019: unresolved external symbol __acrt_thread_detach referenced in function __scrt_dllmain_crt_thread_detach
 : warning LNK4088: image being generated due to /FORCE option; image may not run
msvcprt.lib(locale0_implib.obj) : warning LNK4210: .CRT section exists; there may be unhandled static initializers or terminators

这当然不是解决方案，也不保证在任何情况下都可以使用，但是至少对我的代码有效。

哪个库包含_is_c_termination_complete

2 个答案: