generic enum produces invalid c code

[Le0Developer]

follow up of #23269

V doctor:

V full version: V 0.4.7 62c69e8.caa0c46
OS: macos, macOS, 15.2, 24C101
Processor: 8 cpus, 64bit, little endian, Apple M2

getwd: /Users/leodev/p/v/cluedo
vexe: /Users/leodev/bin/v/v
vexe mtime: 2024-08-26 08:17:23

vroot: OK, value: /Users/leodev/bin/v
VMODULES: OK, value: /Users/leodev/.vmodules
VTMP: OK, value: /tmp/v_501

Git version: git version 2.39.5 (Apple Git-154)
Git vroot status: weekly.2024.34-46-gcaa0c464 (866 commit(s) behind V master)
.git/config present: true

CC version: Apple clang version 16.0.0 (clang-1600.0.26.6)
thirdparty/tcc status: thirdparty-macos-arm64 713692d4

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

import os

fn prompt_enum[T](prompt string) T {
	full_prompt := '${prompt}: '
	for {
		s := os.input_opt(full_prompt) or { continue }
		if x := T.from(s) {
			return x
		}
	}
	panic('unreachable')
}

enum EnumA {
	a
	b
	c
}

enum EnumB {
	x
	y
	z
}

fn main() {
	prompt_enum[EnumA]('Which enum A?')
}

What did you expect to see?

Successful compilation

What did you see instead?

================== C compilation error (from cc): ==============
cc:        |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc: /tmp/v_501/repro.01JFZFD586X9D8C8DGWCD7V5HC.tmp.c:18755:13: error: call to undeclared function 'main__EnumA__static__from'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
cc:  18755 |                 if (_t2 = main__EnumA__static__from(s), !_t2.is_error) {
cc:        |                           ^
cc: /tmp/v_501/repro.01JFZFD586X9D8C8DGWCD7V5HC.tmp.c:18755:11: error: assigning to '_result_main__EnumA' (aka 'struct _result_main__EnumA') from incompatible type 'int'
cc:  18755 |                 if (_t2 = main__EnumA__static__from(s), !_t2.is_error) {
cc:        |                         ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc: 3 warnings and 2 errors generated.
... (the original output was 16 lines long, and was truncated to 8 lines)
================================================================
(You can pass `-cg`, or `-show-c-output` as well, to print all the C error messages).
builder error: 
==================
C error found. It should never happen, when compiling pure V code.
This is a V compiler bug, 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 .

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_{Huly®: V_0.6-21704}