c++ - 使用 xlC 13.1.2 在 AIX 7.1 上编译 boost C++ 库

Question

我正在尝试使用 xlC 编译器在 AIX 上编译 boost C++ 库的正则表达式部分并将其用作 64 位动态库，因为我需要比较几个 C++ 正则表达式库和内置解决方案的性能，而 boost 似乎是一个可行的候选者。

这是我的确切操作系统和编译器版本:

$ uname -a
AIX host_name 1 7 00F9A2144C00
$ xlC -qversion
IBM XL C/C++ for AIX, V13.1.2 (5725-C72, 5765-J07)
Version: 13.01.0002.0000

因为我没有 root 权限，我实际上无法安装 boost 库，我只是想将正则表达式部分编译成一个共享对象文件，并为我的测试应用程序获取所有需要的头文件。我试过编译最新的可用版本(1.59.0)，还有1.55.0版本，因为我发现IBM已经发布了boost的源代码补丁:

http://www-01.ibm.com/support/docview.wss?uid=swg27042921

我使用以下命令编译 boost 并将 header 和共享对象文件复制到我的开发文件夹:

bootstrap.sh --with-toolset=vacpp --prefix=/my/user/directory --exec-prefix=/my/user/directory
./b2 address-model=64 cxxflags=-q64 cflags=-q64
b2 tools/bcp
./dist/bin/bcp boost/regex.hpp /my/include/directory
cp stage/lib/libboost_regex.so /my/library/directory

我知道我可以添加 --with-libraries=regex 标志来只编译正则表达式部分，但这与我的问题无关。

对于这两个版本，无论有没有修补 boost 源代码，我都遇到了同样的问题。

首先:我已经编译了一些库，并链接到我的简单测试应用程序，例如 PCRE C++ regex 库。当我还尝试使用 -lboost_regex 编译标志链接 boost regex 库时，出现以下错误:

ld: 0706-006 Cannot find or open library file: -l boost_regex
ld:open(): No such file or directory
make: The error code from the last command is 255.

这是通过添加 -brtl 编译标志来解决的，据我所知，只有在我尝试链接静态库时才需要它，所以在我看来就像 libboost_regex .so 实际上是 libboost_regex.a

其次:当我将行 #include "boost/regex.hpp" 添加到我的代码中时，出现编译错误:

"/opt/IBM/xlC/13.1.2/include/xtr1common", line 217.19: 1540-0130 (S) "false_type" is not declared.
"/opt/IBM/xlC/13.1.2/include/xtr1common", line 223.19: 1540-0130 (S) "true_type" is not declared.
"/opt/IBM/xlC/13.1.2/include/xtr1common", line 229.19: 1540-0130 (S) "true_type" is not declared.
"/opt/IBM/xlC/13.1.2/include/xtr1common", line 235.19: 1540-0130 (S) "true_type" is not declared.
"/opt/IBM/xlC/13.1.2/include/xtr1common", line 244.11: 1540-0130 (S) "false_type" is not declared.
"/opt/IBM/xlC/13.1.2/include/xtr1common", line 250.11: 1540-0130 (S) "true_type" is not declared.
make: The error code from the last command is 1.

我的测试应用程序非常简单。这些是我的 Makefile 的内容:

all:
    /opt/IBM/xlC/13.1.2/bin/xlC -q64 -Iinclude -Llibs -lpcrecpp main.cpp -o regexp_test

clean:
    rm regexp_test

这是我非常基本的测试应用程序的源代码:

#include <iostream>
#include <string.h>

#ifndef __IBMCPP_TR1__
#define __IBMCPP_TR1__ 1
#include <regex>
#undef __IBMCPP_TR1__
#endif

#define __IBMCPP_TR1__ 1

/* Regular expression libraries to be included */
#include <sys/types.h>
#include <regex.h>
#include "pcrecpp.h"
// #include "boost/regex.hpp"
#include "deelx.h"

int main(int argc, char **argv)
{
    if(argc != 4){
        std::cerr << "Use: ./regexp_test <posix|tr1|pcre|deelx> value regexp" << std::endl;
        return 1;
    }

    int status;
    char buffer[256], regexp[256];
    snprintf(buffer,sizeof(buffer),argv[2]);
    snprintf(regexp,sizeof(regexp),argv[3]);
    std::string buffer_string = buffer;
    bool match = false;

    if(strcmp(argv[1],"posix")==0){

        regex_t comp;
        if (regcomp(&comp, regexp, REG_EXTENDED) != 0) {
            std::cerr << "The regular expression '" << regexp << "' could not be compiled!" << std::endl;
            return 1;
        } else {
            status = regexec(&comp, buffer, (size_t) 0, NULL, 0);
            regfree(&comp);
            if (status == 0) {
                match = true;
            }
        }

    } else if(strcmp(argv[1],"tr1")==0){

        try {
            std::tr1::smatch matches;
            std::tr1::regex rgx(regexp);
            status = std::tr1::regex_search(buffer_string, matches, rgx);
            if(status){
                match = true;
            }
        }
        catch(std::tr1::regex_error& re)
        {
            std::cerr << "TR1 exception caught!" << std::endl;
        }

    } else if(strcmp(argv[1],"pcre")==0){

        pcrecpp::RE re(regexp);
        if(re.PartialMatch(buffer)){
            match = true;
        }

    } else if(strcmp(argv[1],"deelx")==0){

        static CRegexpT <char> deelx_regexp(regexp, IGNORECASE | MULTILINE);
        MatchResult result = deelx_regexp.Match(buffer);
        if(result.IsMatched()){
            match = true;
        }

    } else {
        std::cerr << "Use: ./regexp_test <posix|tr1|pcre|deelx> value regexp" << std::endl;
        return 1;
    }

    if (!match) {
        std::cout << "The regular expression '" << regexp << "' does NOT match the value '" << buffer << "'." << std::endl;
    } else {
        std::cout << "The regular expression '" << regexp << "' matches the value '" << buffer << "'." << std::endl;
    }

    return 0;
}

如何解决这些问题？任何提示或建议将不胜感激。

Answer 1

我已经找到了解决我的两个问题的方法。

链接问题:

我找到了这篇文章: https://web.archive.org/web/20100514132209/http://durgaprasad.wordpress.com/2006/09/28/problems-with-linking-of-shared-libraries-in-aix/

Problems with linking of shared libraries in AIX September 28, 2006 at 8:13 am (AIX, C/C++) Normally, in Solaris, Linux and other common platforms, shared libraries are represented with .so/.sl suffix. Static libraries are represented with .a suffix in filenames. But in AIX, static libraries have .a suffix and shared libraries can have either .so or .a suffix.

when we try to compile a c file which uses shared library with .so suffix, it wont succeed by default. It gives a compilation error. Additionally we have to pass “-Wl,-brtl” flag to the compiler. “-Wl” is to say that it is a flag to the linker, so “-brtl” is internally passed to the linker [ld]. “-brtl” says that it should consider files with .so suffix also as shared libraries. There is no need to pass this flag when your shared library contains .a suffix. This type of linking is loadtime linking.

When we want to access a shared library at runtime using dlopen & dlsym calls, it is called runtime linking. In this case, we wont get any compilation errors. If the shared library contains .a suffix, we wont get any errors at runtime also. But if the shared library contains .so suffix, we get segmentation fault at runtime. Confusing thing is, it succesfully executes dlopen call, but at the time of dlsym, it exits with segmentation fault. If we give “-Wl-brtl” flag to compiler at compilation time, runtime linking goes fine.

它详细说明在 AIX 上，共享库可以同时具有 .so 和 .a 后缀，并且要指示编译器搜索 .so 文件，您需要包含 -brtl旗帜。它还指示包括 -Wl标志，以便将链接标志直接传递给链接器 (ld)，但我发现此版本的 xlC 已弃用此功能。

代码的问题:

预处理器指令#define __IBMCPP_TR1__ 1导致 boost regex 库因编译错误而失败。只有我也在使用的 AIX 的内置 tr1 正则表达式才需要这个定义，但事实证明它只对 #include <regex> 是必需的。部分，我可以省略第二个定义。