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C++ file doesn't recognize function defined in assembly file

I'm trying to learn some assembly code and I'm following a tutorial proposed by a book, I've got a C++ code defined as follows (Ch02_01.cpp) :

#include <iostream>


using namespace std;

extern "C" int IntegerAddSub_(int a, int b, int c, int d);
int main() {
    int a, b, c, d, result;
    a = 101;  b = 34; c = -190; d = 25;
    result = IntegerAddSub_(a, b, c, d);
    cout << "result = " << result << n1;
    return 0;
}

Knowing that The function IntegerAddSub_ is defined in an assembly file (asm extension) in the folder as follows (Ch02_01.asm) :

; extern "C" int IntegerAddSub_(int a, int b, int c, int d);

        .code
IntegerAddSub_ proc
; Calculate a + b + c -d
        mov eax, ecx      ;eax = a
        add eax, edx      ;eax = a + b
        add eax, r8d      ;eax = a + b + c
        sub eax, r9d      ;eax = a + b + c - d
        ret               ; return result to caller

IntegerAddSub_ endp
        end

Error message :

Error message :
/home/.local/share/JetBrains/Toolbox/apps/CLion/ch-0/222.3345.126/bin/cmake/linux/bin/cmake --build /home/Assembly/cmake-build-debug --target Assembly -j 16
[1/1] Linking CXX executable Assembly
FAILED: Assembly 
: && /usr/bin/c++ -g  CMakeFiles/Assembly.dir/Ch02_01.cpp.o -o Assembly   && :
/usr/bin/ld: CMakeFiles/Assembly.dir/Ch02_01.cpp.o: in function `main':
/home/Assembly/Ch02_01.cpp:25: undefined reference to `IntegerAddSub_'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.

I think the semantics of the error is simply that the C++ file did not recognize the function defined in the assembler file.

According to the exchanges in the comments, i'll add the following informations: I'am using CLION (From Jetbrains) and here is my CMakeLists.txt

cmake_minimum_required(VERSION 3.23)
project(Assembly)

set(CMAKE_CXX_STANDARD 14)
set ( SOURCES
      Ch02_01.asm
    )
add_executable(Assembly
        Ch02_01.cpp)

And I don't know how to compile that using g++, it never recognizes the function from the ASM file, how can I successfully compile that, please? I am in Ubuntu. Thanks

Solution

  • You need to tell CMake that the project includes code too - or if that's what it actually is.

    Example:

    cmake_minimum_required(VERSION 3.22)
project(Assembly CXX ASM_NASM) # or perhaps it should be ASM_MASM

set(CMAKE_CXX_STANDARD 14)

add_executable(Assembly Ch02_01.asm Ch02_01.cpp)

    This makes it at least try to compile the asm file, but for me it fails:

    [ 33%] Building ASM_NASM object CMakeFiles/Assembly.dir/Ch02_01.asm.o
/home/ted/proj/stackoverflow/assembly/Ch02_01.asm:3: warning: label alone on a line without a colon might be in error [-w+label-orphan]
/home/ted/proj/stackoverflow/assembly/Ch02_01.asm:4: error: parser: instruction expected
/home/ted/proj/stackoverflow/assembly/Ch02_01.asm:12: error: label `IntegerAddSub_' inconsistently redefined
/home/ted/proj/stackoverflow/assembly/Ch02_01.asm:4: info: label `IntegerAddSub_' originally defined here
/home/ted/proj/stackoverflow/assembly/Ch02_01.asm:12: error: parser: instruction expected
/home/ted/proj/stackoverflow/assembly/Ch02_01.asm:13: warning: label alone on a line without a colon might be in error [-w+label-orphan]
make[2]: *** [CMakeFiles/Assembly.dir/build.make:76: CMakeFiles/Assembly.dir/Ch02_01.asm.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:83: CMakeFiles/Assembly.dir/all] Error 2
make: *** [Makefile:91: all] Error 2