Trouble Linking

[eternal dock]

Been having a bit of trouble linking two .o files.
First .o file is generated from compiling a .c file to a .ll file and then to a .o file
Second .o file is generated from a .zig file

When I attempt to link both together, I get the following error (using WSL btw)

LLD Link... ld.lld: error: duplicate symbol: _start
>>> defined at /usr/lib/gcc/x86_64-linux-gnu/11/../../../x86_64-linux-gnu/crt1.o:(_start)
>>> defined at main
>>>            main.o:(.text+0x0)

Here are the commands I used in order (last one causes the error)

clang -O3 -S -emit-llvm helper.c -o helper.ll
llc -filetype=obj helper.ll -o helper.o      
zig cc -c helper.ll -o helper.o
zig build-obj main.zig -O ReleaseSmall       
zig cc -o main main.o helper.o -lc

I'm just trying to compile two simple files together, both don't contain complex code (I can share them if needed)

*Using the latest Zig version (master)

[frosty elk]

First .o file is generated from compiling a .c file to a .ll file and then to a .o file
why

why not just emit an object file from the .c file

you can provide multiple file inputs to build-exe, i.e zig build-exe helper.c main.zig -lc

[eternal dock]

Because the actual input I'll be using from here onwards is going to be a .ll file, not a .c (just using a .c file rn for testing purposes)

[frosty elk]

could you explain a bit more on why it'll be from an .ll file?

this is sort of an XY question, there might just be a better way

[eternal dock]

For context, in the future, I'll be generating textuall llvm ir from a frontend and need it to link with my zig virtual machine
That's why the input would be a .ll file

I'm using clang just now because we've yet to get the textual ir generation working

just testing purposes really

[frosty elk]

i see

[eternal dock]

im testing linking with 2 simple files, if it works, we'll then test with the vm

[frosty elk]

if im remembering right, the flag is called something like -no-start-files for the last command you run

something like that

[safe tree]

found this https://github.com/ziglang/zig/issues/16871

[frosty elk]

yeah the flag is called -nostartfiles

do zig cc -o main main.o helper.o -lc -nostartfiles

[eternal dock]

tried, it seems I get the same error unfortunately

[eternal dock]

I'll look into this thanks

[frosty elk]

to apply the fix in that issue, try doing zig build-obj main.zig -O ReleaseSmall -lc

[eternal dock]

It works now!

Thank you both very much

[frosty elk]

interesting, im confused why -nostartfiles doesn't work