std lib test suite: fix illegal behavior found by valgrind

[ghost]

this addresses some of the warnings in #24753

[jedisct1]

That fix doesn't make sense.

Maybe move var ad = m; later, after m has been initialized instead.

[rpkak]

I also just fixed the IOUring errors. This is my diff:

diff --git a/lib/std/os/linux/IoUring.zig b/lib/std/os/linux/IoUring.zig
index 62a87ac103..5c7e5ff1c2 100644
--- a/lib/std/os/linux/IoUring.zig+++ b/lib/std/os/linux/IoUring.zig@@ -1692,7 +1692,9 @@ pub const BufferGroup = struct {
pub fn get(self: *BufferGroup, cqe: linux.io_uring_cqe) ![]u8 {
const buffer_id = try cqe.buffer_id();
const used_len = @as(usize, @intCast(cqe.res));
- return self.get_by_id(buffer_id)[0..used_len];+ const buf = self.get_by_id(buffer_id)[0..used_len];+ std.valgrind.memcheck.makeMemDefinedIfAddressable(buf);+ return buf;
}
// Release buffer from CQE to the kernel.
@@ -4404,9 +4406,7 @@ fn expect_buf_grp_cqe(
try testing.expectEqual(posix.E.SUCCESS, cqe.err());
// get buffer from pool
- const buffer_id = try cqe.buffer_id();- const len = @as(usize, @intCast(cqe.res));- const buf = buf_grp.get_by_id(buffer_id)[0..len];+ const buf = try buf_grp.get(cqe);
try testing.expectEqualSlices(u8, expected, buf);
return cqe;

[ghost]

I also just fixed the IOUring errors. This is my diff:

I committed it, feel free to change the author

[rpkak]

I also just fixed the IOUring errors. This is my diff:

I committed it, feel free to change the author

That's not important to me.

[rpkak]

I think b349081 and fc1a66e can be reverted now.

[ghost]

I think b349081 and fc1a66e can be reverted now.

Tested, reverting either increases the amount of valgrind errors.

[andrewrk]

I edited the title to better reflect the task: fixing things, not suppressing warnings

[ghost]

this also errors out when running the std lib test suite
how do I fix this?

[ghost]

@jedisct1 any ideas on this? I could just hardcode 8, but that seems like a bug waiting to happen.

[ghost]

no valgrind errors on linux, tested with .debug_stack_frames_count = 8 (don't know how to fix that)
valgrind.txt

[andrewrk]

I have a feeling this is never going to get merged. Please do one at a time, and no drafts