Unable to link obj files generated by LLVM compiler using MS Linker

I used the llvm online compiler to compile my C example code,

int main() { return 0; }

generated LLVM assembly,

 ; ModuleID = '/tmp/webcompile/_31588_0.bc'
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

define i32 @main() nounwind uwtable {
  %1 = alloca i32, align 4
  store i32 0, i32* %1
  ret i32 0
}

then I compiled the LLVM assembly into an obj file,

llc -filetype=obj a.ll

when I tried to link the obj file with link.exe a.o, I got an error

 fatal error LNK1107: invalid or corrupt file: cannot read at 0x438

How can I generate the correct obj file for submission to link.exe?


Additional Information

  • I built LLVM using Visual Studio 11. I did not have cygwin installed.
  • link.exe also from Visual Studio 11
  • LLVM was created from the latest source code.

If I compile the same code using the VC ++ compiler into an assembly, it looks like this:

; Listing generated by Microsoft (R) Optimizing Compiler Version 17.00.50402.0 

include listing.inc

INCLUDELIB LIBCMT
INCLUDELIB OLDNAMES

PUBLIC  main
; Function compile flags: /Odtp
_TEXT   SEGMENT
main    PROC
; File c:\tmp\u.c
; Line 1
    xor eax, eax
    ret 0
main    ENDP
_TEXT   ENDS
END

llc -filetype=asm j.llgenerates the following code. It also does not work with ml.exe.

    .def     _main;
    .scl    2;
    .type   32;
    .endef
    .text
    .globl  _main
    .align  16, 0x90
_main:                                  # @main
# BB#0:
    pushl   %eax
    movl    $0, (%esp)
    xorl    %eax, %eax
    popl    %edx
    ret
0
source share
2

IR x86-64/linux, . , llc ( ) ELF , COFF. , link.exe .

, , :

+1

Source: https://habr.com/ru/post/1541015/


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