invalid c generated for my complex `arrays.fold` call

[dy-tea]

Describe the bug

Code snippet that seems to cause problems is in zulip/bot.v lines 66:88

Didn't look into exactly what is causing the cgen issue, maybe a smaller repro can be made.

		arrays.fold(r.events, []Event{}, fn (acc []Event, a json2.Any) []Event {
			typ := json2.decode[ResponseStub](a.str()) or { ResponseStub {.unknown} }.etyp
			res := match typ {
				.message {
					Event(json2.decode[MessageEvent](a.str()) or {
						panic(err)
					})
				}
				.reaction {
					Event(json2.decode[ReactionEvent](a.str()) or {
						panic(err)
					})
				}
				else {
					eprintln('UNSUPPORTED EVENT TYPE')
					none
				}
			}
			if r := res {
				return arrays.append(acc, [r])
			}
			return acc
		})

❯ v run echobot.v
================== C compilation error (from tcc): ==============
cc: /tmp/v_1000/echobot.01KGDYAXWWYWK4TXYP1JTFQD4A.tmp.c:6504: warning: type defaults to int
cc: /tmp/v_1000/echobot.01KGDYAXWWYWK4TXYP1JTFQD4A.tmp.c:6504: error: ';' expected (got "*")
=================================================================
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. 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 .

Reproduction Steps

See: https://github.com/dy-tea/vulip

git clone https://github.com/dy-tea/vulip
cd vulip
v run echobot.v

Expected Behavior

Should compile, or maybe not; I am not entirely sure what I was doing here.

Current Behavior

.

Possible Solution

No response

Additional Information/Context

No response

V version

V 0.5.0 50a7d53

Environment details (OS name and version, etc.)

V full version	V 0.5.0 a965a39.50a7d53
OS	linux, "CachyOS"
Processor	12 cpus, 64bit, little endian, 13th Gen Intel(R) Core(TM) i5-1335U
Memory	4.19GB/15.31GB
V executable	/home/dylan/Repos/v/v
V last modified time	2026-01-28 17:56:57
V home dir	OK, value: /home/dylan/Repos/v
VMODULES	OK, value: /home/dylan/.vmodules
VTMP	OK, value: /tmp/v_1000
Current working dir	OK, value: /home/dylan
Git version	git version 2.52.0
V git status	weekly.2026.02-182-g50a7d536
.git/config present	true
cc version	cc (GCC) 15.2.1 20260103
gcc version	gcc (GCC) 15.2.1 20260103
clang version	clang version 21.1.6
tcc version	tcc version 0.9.28rc 2025-02-13 HEAD@f8bd136d (x86_64 Linux)
tcc git status	thirdparty-linux-amd64 696c1d84
emcc version	N/A
glibc version	ldd (GNU libc) 2.42

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