从DLL创建符号库以与MINGW32一起使用

Question

I'm developing an application at work using C++, Qt, Mingw32 and Netbeans. I need to use an in house API that has been developed by the software group in the company. I have the symbol libraries .lib files for the DLLs i need to link against, but i cannot use these libs with Mingw32, it works fine with Microsoft Visual Studio.

Does anyone know if there is a way to export the symbols and create a .a symbol library that works with Mingw32 ? If not i'll have to go over to Visual Studio i guess.

I have tried using the program "pexports" to create a .def file and dlltool, but that didn't work. Still got unreferenced symbol errors, then i added the symbols it complained about to the .def, because they weren't there and it stopped complaining and compiled. But the program crashes. I tried the same code in Visual Studio and it compiles and runs fine.

Answer 1

Have you considered dynamically loading the DLL? LoadLibrary, GetProcAddress, etc. You can probably easily write a class that encapsulates all the DLL's entry points, loading and unloading the library, and does all the #typedefs, etc. It's grunt work but if it's an in-house library there probably aren't too many entry points?

Import libs are overrated. :p

Answer 2

不确定是否有帮助，但是您可能希望查看本指南 。

Answer 3

Here's how I did that for the mysql library.

Create a list of exports using dllwrap:

dllwrap --export-all-symbols --output-def libmysql.def libmysql.dll --implib liblibmysql.a

This creates a list of exports in the .def file but the name mangling is incorrect. Edit the .def file in a text editor and remove the '@' symbols. The symbol names typically also have a number appended to them as well. I don't know how to determine the correct name except by experimentation:

Run the following to create a netbeans compatible library:

dlltool --input-def libmySQL.def --dllname libmySQL.dll --output-lib libMySQLclient.a -k

Compile with it and you'll get undefined symbols. The undefined symbols will have the correct decorations. Edit the .def file again and correct the symbol names. Re-run dlltool to get the correct .a library file.

Answer 4

Have you tried linking the DLL directly, rather than a .a/.lib? MinGW is usually happy to do that for you.

Answer 5

我放弃了，有人说由于名字改错，不可能在Microsofts编译器上使用C ++导出来编译dll。