C error on &(arr.last() as Type)

[islonely]

V version: V 0.4.9 11c59cf, press to see full `v doctor` output

V full version	V 0.4.9 4225a34.11c59cf
OS	macos, macOS, 15.2, 24C101
Processor	8 cpus, 64bit, little endian, Apple M3
Memory	0.47GB/16GB
V executable	/Users/adamoates/v/v
V last modified time	2025-01-19 19:21:00
V home dir	OK, value: /Users/adamoates/v
VMODULES	OK, value: /Users/adamoates/.vmodules
VTMP	OK, value: /tmp/v_501
Current working dir	OK, value: /Users/adamoates/repos/cyberian_tiger
Git version	git version 2.39.5 (Apple Git-154)
V git status	weekly.2025.1-88-g11c59cf8 (1 commit(s) behind V master)
.git/config present	true
cc version	Apple clang version 16.0.0 (clang-1600.0.26.6)
gcc version	Apple clang version 16.0.0 (clang-1600.0.26.6)
clang version	Apple clang version 16.0.0 (clang-1600.0.26.6)
tcc version	tcc version 0.9.28rc 2024-02-05 HEAD@105d70f7 (AArch64 Darwin)
tcc git status	thirdparty-macos-arm64 713692d4
emcc version	N/A
glibc version	N/A

What did you do?
./v -g -o vdbg cmd/v && ./vdbg /Users/adamoates/Documents/test.v && /Users/adamoates/Documents/test

@[heap]
struct Foo {
mut:
	val int
}

@[heap]
struct Bar {
mut:
	val int
}

interface FooBar {
mut:
	val int
}

fn main() {
	mut fbs := []&FooBar{}
	fbs << &Foo{1}
	_ := &(fbs[0] as Foo)
	_ := &(fbs.last() as Foo)
}

What did you see?

================== C compilation error (from cc): ==============
cc: /tmp/v_501/test.01JJ035YNBY47QPGNK9EGP6P59.tmp.c:5766:18: error: cannot take the address of an rvalue of type 'main__Foo' (aka 'struct main__Foo')
cc:  5766 |         {main__Foo* _ = &(({ main__FooBar* _t2 = (*(main__FooBar**)array_last(fbs)); *(main__Foo*)__as_cast(_t2->_main__Foo,v_typeof_interface_idx_main__FooBar(_t2->_typ), 103); }));}
cc:       |                         ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc: 1 error generated.
================================================================
(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 .

What did you expect to see?

Expected code to compile and for &(fbs.last() as Foo) to be equal to &(fbs[0] as Foo)

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[huly-for-github]

Connected to Huly®: V_0.6-21956

[yuyi98]

It can work now.

@[heap]
struct Foo {
mut:
	val int
}

@[heap]
struct Bar {
mut:
	val int
}

interface FooBar {
mut:
	val int
}

fn main() {
	mut fbs := []&FooBar{}
	fbs << &Foo{1}
	a := &(fbs[0] as Foo)
	println(a)
	b := &(fbs.last() as Foo)
	println(b)
}

PS D:\Test\v\tt1> vdbg run .
&Foo{
    val: 1
}
&Foo{
    val: 1
}

[felipensp]

It can work now.

@[heap]
struct Foo {
mut:
val int
}

@[heap]
struct Bar {
mut:
val int
}

interface FooBar {
mut:
val int
}

fn main() {
mut fbs := []&FooBar{}
fbs << &Foo{1}
a := &(fbs[0] as Foo)
println(a)
b := &(fbs.last() as Foo)
println(b)
}

PS D:\Test\v\tt1> vdbg run .
&Foo{
val: 1
}
&Foo{
val: 1
}

Hi @yuyi98 , it works on tcc, but not in gcc or clang. 👍🏻