compiler bug: compiler confused by function called vbytes() calling array.vbytes()

[thomas-mangin]

V doctor:

OS: macos, macOS, 12.0.1, 21A559
Processor: 10 cpus, 64bit, little endian, Apple M1 Max
CC version: Apple clang version 13.0.0 (clang-1300.0.29.3)

getwd: /Users/thomas/bug
vmodules: /Users/thomas/.vmodules
vroot: /Users/thomas/Unix/v-latest
vexe: /Users/thomas/Unix/v-latest/v
vexe mtime: 2021-11-29 09:04:46
is vroot writable: true
is vmodules writable: true
V full version: V 0.2.4 24ba660.c14c324

Git version: git version 2.34.0
Git vroot status: weekly.2021.47-49-gc14c3241
.git/config present: true
thirdparty/tcc status: thirdparty-macos-amd64 689c8a02

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

type Buffer = []byte

pub fn (mut sb Buffer) vbytes() string {
	return sb[0..sb.len].vbytes().str()
}

fn main() {
	mut b := Buffer([]byte{cap:10})
	b << 1
	b << 2
	println(b.vbytes())
}

What did you expect to see?

no crash

What did you see instead?

==================
       ^
/tmp/v_501/bug.10506693758119739925.tmp.c:10602:26: error: passing 'int' to parameter of incompatible type 'string' (aka 'struct string')
        string _t1 = string_str(main__Buffer_vbytes_static(array_slice(*sb, 0, sb->len)));
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/tmp/v_501/bug.10506693758119739925.tmp.c:9362:26: note: passing argument to parameter 's' here
string string_str(string s) {
                         ^
2 errors generated.
...
==================
(Use `v -cg` to print the entire error message)

builder error: 
==================
C error. This should never happen.

This is a compiler bug, please report it using `v bug file.v`.

https://github.com/vlang/v/issues/new/choose

You can also use #help on Discord: https://discord.gg/vlang

[felipensp]

sb[0..sb.len].vbytes() does the code generate recursive call to Buffer.vbytes()

[felipensp]

&u8 and voidptr does implements vbytes(), not byte. What do you think @medvednikov @spytheman ?

[JalonSolov]

byte is an alias for u8 now, and it is also deprecated. Since it is deprecated, I don't see any reason to make this work for byte type.

However, even changing byte to u8 in the example, there is still an error:

/tmp/v_1000/../../../../../../home/jalon/x.v:4: warning: implicit declaration of function 'main__Buffer_vbytes_static'
/tmp/v_1000/../../../../../../home/jalon/x.v:4: error: cannot convert 'int' to 'struct string'

The line in question is

	return sb[0..sb.len].vbytes().str()

[felipensp]

byte is an alias for u8 now, and it is also deprecated. Since it is deprecated, I don't see any reason to make this work for byte type.

However, even changing byte to u8 in the example, there is still an error:

/tmp/v_1000/../../../../../../home/jalon/x.v:4: warning: implicit declaration of function 'main__Buffer_vbytes_static'
/tmp/v_1000/../../../../../../home/jalon/x.v:4: error: cannot convert 'int' to 'struct string'

The line in question is

	return sb[0..sb.len].vbytes().str()

Yes. This failure is being treated in another PR which I have submitted.

[felipensp]

string _t1 = string_str(byteptr_vbytes(&array_slice(*sb, 0, sb->len)));

cc: /tmp/v_1000/bug.01J8GVC9EWGNTR2VFHP39SKJHC.tmp.c:13334: warning: assignment from incompatible pointer type
cc: /tmp/v_1000/bug.01J8GVC9EWGNTR2VFHP39SKJHC.tmp.c:13334: error: too few arguments to function

We must fix this case... since byteptr_vbytes has 2 params.