C error undeclated function: spawn method with param as interface defined in another module

[jorgeluismireles]

Describe the bug

spawn a method with a parameter implementing an interface defined in another module causes C error. Works if

• we don't call the spawn
• The interface/struct are local (not in another module).

Reproduction Steps

File bugs/record.v with main:

module main

import records

fn web(recorder records.Recorder) {
	for {
		// web server simulated
	}
}

struct Serial {

}

fn (mut s Serial) write_record(record &records.Record) ! {
	// do something...
	return 
}

fn main() {
	mut s := &Serial{}
	spawn web(s)
}

File bugs/records/record.v

module records

pub interface Recorder {
mut:
	write_record(record &Record) ! 
}

pub struct Record {

}

Expected Behavior

No C error

Current Behavior

$ v -show-c-output run bugs/record.v
======== Output of the C Compiler (/home/jorge/v/thirdparty/tcc/tcc.exe) ========
/tmp/v_1000/record.01JHKAQ154EC1PPEZ27ME0AMY5.tmp.c:1708: error: 'I_main__Serial_to_Interface_recordarg' undeclared
=================================================================================
======== Output of the C Compiler (cc) ========
/tmp/v_1000/record.01JHKAQ154EC1PPEZ27ME0AMY5.tmp.c: In function ‘main__web_thread_wrapper’:
/tmp/v_1000/record.01JHKAQ154EC1PPEZ27ME0AMY5.tmp.c:1708:25: error: ‘I_main__Serial_to_Interface_recordarg’ undeclared (first use in this function); did you mean ‘I_main__Serial_to_Interface_records__Recorder’?
 1708 |         arg->fn(        I_main__Serial_to_Interface_recordarg->arg1__Recorder(arg->arg1));
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                         I_main__Serial_to_Interface_records__Recorder
/tmp/v_1000/record.01JHKAQ154EC1PPEZ27ME0AMY5.tmp.c:1708:25: note: each undeclared identifier is reported only once for each function it appears in
===============================================
No such file or directory; code: 2

Possible Solution

No response

Additional Information/Context

No response

V version

V 0.4.9 da3112e.9ba294b

Environment details (OS name and version, etc.)

V full version	V 0.4.9 da3112e.9ba294b
OS	linux, Ubuntu 22.04.5 LTS
Processor	4 cpus, 64bit, little endian, Intel(R) Core(TM) i3-4150 CPU @ 3.50GHz
Memory	0.58GB/3.7GB
V executable	/home/jorge/v/v
V last modified time	2025-01-14 21:00:43
V home dir	OK, value: /home/jorge/v
VMODULES	OK, value: /home/jorge/.vmodules
VTMP	OK, value: /tmp/v_1000
Current working dir	OK, value: /home/jorge
Git version	git version 2.34.1
V git status	weekly.2025.1-51-g9ba294bc
.git/config present	true
cc version	cc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
gcc version	gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
clang version	Ubuntu clang version 14.0.0-1ubuntu1.1
tcc version	tcc version 0.9.28rc 2024-07-31 HEAD@1cee0908 (x86_64 Linux)
tcc git status	thirdparty-linux-amd64 0134e9b9
emcc version	emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 3.1.5 ()
glibc version	ldd (Ubuntu GLIBC 2.35-0ubuntu3.8) 2.35

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[huly-for-github]

Connected to Huly®: V_0.6-21901

[jorgeluismireles]

Workaround, move spawn within web function:

fn web(recorder records.Recorder) {
	spawn fn() {
		for { } // web server here
	}()
}

struct Serial {

}

fn (mut s Serial) write_record(record &records.Record) ! {
	return 
}

fn main() {
	mut s := &Serial{}
	web(s)
	// more calls
	for{ } 
}