Link to kernel32.dll using ld.exe

Question

I have assembled my assembly program using the following command:

nasm -f win64 -o test.obj test.asm

test.asm contains a few functions that call Win32 functions like GetStdHandle, HeapAlloc, etc

Normally, I would link one of my assembly projects like so:

ld -LC:/Windows/System32 -lkernel32 -e main -o test.exe test.obj

And it produces a test.exe file, as expected.

However, once I begin to use Win32 functions making use of the heap , like HeapAlloc, HeapFree, GetProcessHeap, I get the following error when linking:

C:\msys64\mingw64\bin\ld.exe: ertr000016.o:(.rdata+0x0): undefined reference to '_pei386_runtime_relocator'

I was then able to assume it has to do with MinGW's files being linked in. So I tried to compile it without them:

ld -nostdlib -nostartfiles -LC:/Windows/System32 -lkernel32 -e main -o test.exe test.obj

and get the following error:

C:\msys64\mingw64\bin\ld.exe: cannot find -lkernel32

So, my question is: how am I supposed to link to kernel32 using ld.exe (without including startfiles or stdlib), because no matter what I try I cannot get it to work.

Thank you for your help!

(I would like an answer that doesn't just tell me use GoLink , please, unless that is the only possible solution).

Answer 1

I've realized that the answer is in the comments now, but I'll post all the steps here just to be clear:

1. Create a .def file for the DLL to be used. This can be done like this:

LIBRARY [name of the dll]
EXPORTS
    [required export #1]
    [required export #2]
    [etc.]

2. Use dlltool.exe to create an archive library file for the .def file:

dlltool -d "[path to the .def file]" -l "[path to output file C, defined below]"

In this command, C is libXXX.a , with XXX changed out for a different name (preferably the name of the original dll without the extension).

3. Instead of using ld.exe , use the linker built into gcc.exe . Also, change out the directory after -L for the directory containing the libXXX.a archive file(s) and change out the dll names that follow for the XXX that was replaced in libXXX.a . These steps, in the context of the original problem, would be:

[Kernel32.def file]

LIBRARY KERNEL32.DLL
EXPORTS
    HeapAlloc
    HeapFree
    [...]

dlltool -d "kernel32.def" -l "libkernel32.a"

gcc -LC:/path/to/this/directory/ -lkernel32 -e main -o test.exe test.obj

Answer 2

 ... -LC:/Windows/System32 -lkernel32...

This is definitely wrong: -lkernel32 will not search for a DLL file named kernel32.dll , but for a library file named libkernel32.a .

... and libkernel32.a is surely not located in C:/Windows/System32 .

How I would go about using dlltool.exe to generate my own libkernel32.a ?

For 64-bit Windows this is easier than for 32-bit Windows (because in 32-bit Windows the fuctions are named differently in the DLL and in the object files).

First, you create a definition file ( .def ) that looks like this:

LIBRARY KERNEL32.DLL
EXPORTS
    HeapAlloc
    HeapFree
    GetProcessHeap
    CreateFileA
    ReadFile

There is a 3rd party tool that can read a .dll file and generate a .def file containing all functions of the DLL; however, you can do this manually and only add the functions that you need.

Then run the following command line:

dlltool -d kernel32.def -l libkernel32.a

Unfortunately, I cannot tell you if this solves your problem with _pei386_runtime_relocator .

EDIT

undefined reference to 'SetFilePointer'

SetFilePointer is also a function defined in kernel32.dll . Did you add SetFilePointer to the .def file?

LIBRARY KERNEL32.DLL
EXPORTS
    HeapAlloc
    HeapFree
    GetProcessHeap
    CreateFileA
    ReadFile
    SetFilePointer     <-- HERE?

I am linking with the following command:

There may be a second problem:

Some versions of gcc require the command line arguments in a certain order. Maybe this is true for ld , too.

Try to move the -L and -l argument to the end of the line:

ld ... -o test.exe test.o -L... -lkernel32