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Between 2020-04-20 00:00:00Z and 2020-04-21 00:00:00Z

[ddnet/ddnet] Issue closed: #2147 Missing Servers

Hello again! I made map on last version on ddnet, load it into ddnet7-server, but when I run it in teeworlds, game freezes like windows xp

(edited)

@TimiT it looks like your map is missing a background

gfx_clear 1

(to debug it, not to fix it)

@TimiT it looks like your map is missing a background

Yes... i should to use bg?

09:35

(to debug it, not to fix it)

Ok :)

oh, could have asked here first

14:58

@Learath2 https://old.reddit.com/r/C_Programming/comments/g4u9wx/question_about_undefined_behavior_time_travel/

r/C_Programming - Question about undefined behavior "time travel"

0 votes and 0 comments so far on Reddit

why this point trigger hook collusion?

Image attachment

check entities

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@heinrich5991 hm, let me take a look at the standard, I'm not completely sure how allowed that reordering is

Hello hello,

its the 0/0 points of the map i think

15:07

reason enough imo :p

bug alarm

Im trying to toggle super/unsuper on the key o with cfg files like i did with deepfly but it doesnt work because it instantly executes the cfg file which leads to the file that gives o the bind unsuper. Like my cfg file is bind o rcon super; exec 4.cfg. It doesnt give me super but executes the cfg file with bind o rcon unsuper; exec 3.cfg

15:09

and it keep staying at it, unsuper bind works, super bind doesnt

keep in mind that yellow hook indicates a hookable tee

not a hookable block?

no

15:10

thats the green hookline

so you have a file 3.cfg with rcon unsuper; bind o exec 4.cfg

15:10

and 4.cfg with rcon super; bind o exec 3.cfg?

15:10

Konsti: ^

@heinrich5991 I can reproduce the compilation on godbolt until clang 3.3

15:15

well until 3.4.1, 3.3 still has it

alright ur sentence brought me to the fix. 3.cfg has to be rcon super; bind o exec 4.cfg and 4.cfg has to be rcon unsuper; bind o exec 3.cfg

15:16

i remember it was not like that on older clients or at least i think so, anyway thanks

np

also send discord unban :)

I think you were banned for a reason

15:17

or rather for a continued flood of reasons

2 years ago:/ cant even access to my tested map

I don't see how any of this reordering he talks about is legal

the last one I kinda see

15:18

as long as the compiler can assume that write returns

15:19

(assuming the compiler can look into all functions)

modifying an object is a side-effect and at sequence points all previous side effects should have taken place and no side effects from the subsequent evaluations shall take place.

so this is wrong?

a++; does indeed have a side-effect it modifies an object, and expression evaluations are sequence points

The “modifying an object” clause is nonsensical because — in combination with sequence point semantics — it forbids the compiler from eliminating the redundant store when a program contains code like this:

>

x=0; x=0;

Why? the compiler can deduce that a modification of the object does not happen here

okay, so this is a misunderstanding of his

thus the modifying an object clause wouldn't apply here, so it's allowed to optimize this unless x is volatile

15:22

This is just how I understand the standard, you can ask like 50 people and get 50 interpretations

15:22

You should try ##C, there are some standard nutjobs there

15:24

The function thing I'm not sure about, C99 5.1.2.3p2 defines what happens when we know the insides of the function, it doesn't seem to say anything about the default assumption though

15:24

(I think you are right about the miscompilation thing though, seeing how clang 3.3 is the last version that does that)

@heinrich5991 okay, I'm not quite right. The compiler is allowed to optimize that last thing, but not because of what I said

15:47

It's because the compiler can determine that the side effect is not needed it can optimize out the second expression

@Learath2 I don't understand

16:05

can you elaborate?

@heinrich5991 do you have a copy of the standard? C99 5.1.2.3p3 says that an actual implementation need not evaluate an expression if it can determine that it's value is not used and it produces no needed side effects

16:09

The second expressions value is not used, and the compiler determines that it produces no needed side effects

16:09

thus optimizes it out

@deen b'jao' doesnt work either

even though there are side-effects as defined by the standard and there is a sequence point

@Learath2 C_Programming seems to agree with you and me: https://old.reddit.com/r/C_Programming/comments/g4u9wx/question_about_undefined_behavior_time_travel/

r/C_Programming - Question about undefined behavior "time travel"

0 votes and 4 comments so far on Reddit

The reordering thing I am indeed wrong about though, the compiler can re-order as it pleases as long as it satisfies the things in 5.1.2.3p5, e.g. doesn't change "observable behaviour"

16:22

p5 in c99, p6 in c11

@heinrich5991 and after an extensive discussion, I no longer think that's a miscompilation

@heinrich5991 why do you think it is? I assumed it was because clang stopped doing it, but that was just a prediction

[ddnet/ddnet] Issue closed: #2113 cl_dyncam not working

@Learath2 I laid out the reasoning in the reddit post

17:27

the compiler cannot create code that aborts when it cannot prove that the code will eventually hit UB

meh, very hard to think about this, it's not legal in the abstract machine to do the reordering, but the actual implementation is allowed to deviate from that if it can prove that the "observable behaviour" doesn't change, as it doesn't know what bar does, I think the optimization is illegal

the observable behavior is different for certain kinds of bars

18:45

hence the optimization is illegal

so the articles premise that "crashes are not side-effecting operations" is wrong

18:47

if the operation couldn't result in an abort, it'd be perfectly legal to reorder the expressions

yes

is the premise wrong though, the standard is pretty specific about what has side effects

20:01

I think only because it changes observable behaviour this is illegal :/

@Learath2 now dissenting voices on the reddit

@heinrich5991 you really should try ##C instead, you can read through the backlog with my chat with dho and caze

do they accept reddit links?

20:17

or should I edit it for them again?

I don't think there'll be a problem with a reddit link

Hey, just want to ask if anyone can help me out, I am out of ideas. My problem: I am about to create a 128 player server for 0.7, so far its working just fine. Now the problem are dummy clients like F-Client or ZillyWoods. The current system functions just as the one from 0.6 for vanilla clients: The client gets the closest 64 tees to see. The first problem that occured was that the client info is wrong, because 0.7 doesnt handle the information in the snaps. So I solved that one by sending disconnect/connect packets with correct information but still faked IDs to the client when they come nearby some other tees. The client of course only knows about 64 tees, and the server doesnt know if its a dummy or not. The solution would be that the client gets the information of the dummy's closest 64 tees when it switches between them, but that is unfortunately impossible to detect. Any ideas?

why is it a problem when dummy and main client see different players?

what do you mean?

20:28

player information is sent to the client using connect and disconnect packets, not via snaps, thats why it doesnt work with 0.7 clients

20:29

that would mean when swapping between dummy and main the other one has wrong information about the tees around

you could keep two sets of player information in the client

wait

one for the dummy and one for the main client

thats what i thought too, but i want to make it serverside

20:29

just in case we get other dummy clients for 0.7 too

with that reasoning you could go for full serverside dummies

20:30

then you wouldn't need a special client

that doesnt work in 0.7, as you cant fake client ids anymore

20:31

they are not in the snaps anymore

why do you need client IDs for this?

for the information to be correct

20:31

your own local client id that you have in the client is set when you enter the server

20:31

and can not be changed

but you don't need to change the client ID the client wants

you need to change your own one, or at least the information like name and clan

20:32

that doesnt work either

20:33

you cannot set m_Local too, that also comes from the connect packet

you can pretend the dummy tee is the new main tee and vice versa

information of your own tee would be wrong then

it would be named [d] you then?

i dont get what exactly you mean, but it would not work

20:36

well, nevermind. but do you know a solution to my initial problem?

20:37

without client modding?

not entirely without

20:43

unless you match IP addresses

what would that help

that's only fuzzy btw

20:44

there are people who have a different IP address than their dummy has

i dont get how that should help

@jao weird, works for me

20:57

@jao same error?

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