CGen: Compilation error when using generics instantiated with 2 different types in the same file

[Yv-vY]

V version: V 0.5.1 d261348, press to see full `v doctor` output

V full version	V 0.5.1 d261348
OS	linux, Linux version 6.19.8-200.fc43.x86_64 (mockbuild@18ffb6c38e5a42008437d0b88e2dfd4e) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.45.1-4.fc43) #1 SMP PREEMPT_DYNAMIC Fri Mar 13 22:06:06 UTC 2026
Processor	16 cpus, 64bit, little endian, AMD Ryzen 7 7800X3D 8-Core Processor
Memory	20.94GB/30.94GB
V executable	/home/yann/Apps/v/v
V last modified time	2026-03-21 18:06:53
V home dir	OK, value: /home/yann/Apps/v
VMODULES	OK, value: /home/yann/.vmodules
VTMP	OK, value: /tmp/v_1000
Current working dir	OK, value: /home/yann/devel/perso/v/bug_reports/bug_generics_func_invalid_arg_types
Git version	git version 2.53.0
V git status	weekly.2026.08-256-gd261348c-dirty
.git/config present	true
cc version	cc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7)
gcc version	gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7)
clang version	clang version 21.1.8 (Fedora 21.1.8-4.fc43)
tcc version	tcc version 0.9.28rc 2025-02-13 HEAD@f8bd136d (x86_64 Linux)
tcc git status	thirdparty-linux-amd64 696c1d84-dirty
emcc version	N/A
glibc version	ldd (GNU libc) 2.42

What did you do?
./v -g -o vdbg cmd/v && ./vdbg my_struct_test.v && my_struct_test

module main

struct MyInt {
	value int
	name  string
}

fn greater_or_equal(a MyInt, b MyInt) bool {
	return a.value >= b.value
}

fn test_ge() {
	s := MyStruct[MyInt]{
		val: MyInt{value: 3, name: '3'}
		others: [
			MyInt{value: 2, name: '2'},
			MyInt{value: 3, name: '3'},
			MyInt{value: 4, name: '4'},
		],
		my_func: greater_or_equal
	}

	s.run()
}

struct Other {
	name string
	size u64
}

fn lower(a &Other, b &Other) bool {
	return a.size < b.size
}

fn test_l() {
	s := MyStruct[&Other]{
		val: &Other{name: 'al', size: 3}
		others: [
			&Other{name: 'joe', size: 42},
			&Other{name: 'jim', size: 2},
		]
		my_func: lower
	}

	s.run()
}

With the generic struct in my_struct.v:

module main

struct MyStruct[T] {
pub:
	val     T
	others  []T
	my_func fn(a T, b T) bool @[required]
}

pub fn (s &MyStruct[T]) run() {
	for c in s.others {
		if s.my_func(s.val, c) {
			println(c.name)
		}
	}
}

What did you see?

================== C compilation error (from tcc): ==============
cc: /tmp/v_1000/my_struct_test.01KM8ZZXG1BHZX77392DZNG6D0.tmp.c:8541: error: cannot convert 'void *' to 'struct main__MyInt'
=================================================================
Try passing `-g` when compiling, to see a .v file:line information, that correlates more with the C error.
(Alternatively, pass `-show-c-output`, to print the full C error message).
builder error: 
==================
C error found while compiling generated C code.
This can be caused by invalid C interop code, C compiler flags, or a V compiler bug.
If your code is pure V and this still happens, please report it using `v bug file.v`,
or goto https://github.com/vlang/v/issues/new/choose .
You can also use #help on Discord: https://discord.gg/vlang .

What did you expect to see?

A successful compilation

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