Can't add same element to cleared map

[ratkingsminion]

Describe the bug

Code: https://play.vlang.io/p/b906a74650

mut ints := map[int]int

ints[5] = 5
assert(ints.len == 1)
ints.clear()
assert(ints.len == 0)
ints[3] = 3
assert(ints.len == 1)
ints.clear()
assert(ints.len == 0)
ints[3] = 3
assert(ints.len == 1) // panics! does not panic if line before is "ints[5] = 5"

Reproduction Steps

Run the code above. It will panic on the last assert()

Expected Behavior

There should be no panic. ints[3] = 3 should add an element to the cleared (empty) map, but it does not.

Current Behavior

Output:

code.v:12: FAIL: fn main.main: assert (ints.len == 1)
V panic: Assertion failed...
v hash: 217b191
/tmp/v_60000/../../../../../../home/admin/v/vlib/builtin/builtin.c.v:136: at _v_panic: Backtrace
/tmp/v_60000/../../../../../../box/code.v:14: by main__main
/tmp/v_60000/../../../../../../tmp/v_60000/code.01J6MJA57JHHGAQJ61AMMGVTY3.tmp.c:26253: by main
Exited with error status 1

Possible Solution

No response

Additional Information/Context

No response

V version

V 0.4.7 217b191

Environment details (OS name and version, etc.)

V full version: V 0.4.7 217b191
OS: linux, Debian GNU/Linux 11 (bullseye) (VM)
Processor: 1 cpus, 64bit, little endian, Intel(R) Xeon(R) CPU E5-2686 v4 @ 2.30GHz

getwd: /home/admin/playground
vexe: /home/admin/v/v
vexe mtime: 2024-08-31 15:25:26

vroot: OK, value: /home/admin/v
VMODULES: OK, value: .vmodules
VTMP: OK, value: /tmp/v_0

Git version: git version 2.30.2
Git vroot status: Error: fatal: detected dubious ownership in repository at '/home/admin/v'
To add an exception for this directory, call:

	git config --global --add safe.directory /home/admin/v
.git/config present: true

CC version: cc (Debian 10.2.1-6) 10.2.1 20210110
thirdparty/tcc status: Error: fatal: detected dubious ownership in repository at '/home/admin/v/thirdparty/tcc'
To add an exception for this directory, call:

	git config --global --add safe.directory /home/admin/v/thirdparty/tcc
 Error: fatal: detected dubious ownership in repository at '/home/admin/v/thirdparty/tcc'
To add an exception for this directory, call:

	git config --global --add safe.directory /home/admin/v/thirdparty/tcc

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[JalonSolov]

It doesn't seem to matter what value is set first. The issue appears to be setting the same key/value after the 2nd .clear() call on the map.

[spytheman]

The memory block holding the keys was not cleared.

@@ -317,6 +317,7 @@ pub fn (mut m map) clear() {
        m.len = 0
        m.even_index = 0
        m.key_values.len = 0
+       unsafe { vmemset(m.key_values.keys, 0, m.key_values.key_bytes * m.key_values.cap) }
 }

fixes that problem locally.