[UserError] How to find your infinite loop

built and tested on 10586, just tested the same build on 10240 and the speed of the game play is a lot faster.

anything known about this?
for now i'll just change the min version for the next update,

 

don't think its frame rate,
need to test with better conditions, just noticed it when i tried it on 2 other machines that have different hardware and different windows builds so,
will have to enable hyper-v tomorrow and try out on the emulators.

my build machine and one other laptop both running 10586 ran the same so i just pointed at the odd man out which was running 10240

any tips for finding the issue?
---
well runs normal in the 10240 emulator so... guess that's not it

 

while debugging an infinite loop issue i've run into experiencing what a staggered frame rate is like while logging a bunch of stuff

didn't realize that could speed up the playback of fixedupdate

can waitforseconds cause a infinite loop type response from the editor (e.g. editor freeze and its cpu to around 15% and memory slowly climbing)

Code (CSharp):

1. Debug.Log("Normal: wait");
2. yield return new WaitForSeconds(Random.Range(0.1f, 2f));
3. agent.SetDestination(check[Random.Range(0, trace.count)]);

"Normal: wait" is the last logged statement before editor freezes
and SetDestination logs its own name before executing anything

i have lots of waitforseconds so might be because this is nested in its own method called from a
coroutine method.. so confusing

 

if i could tell visual studio to break just before a hang i would (if there's a way to do this please tell me)
every while loop in the project is logged (and has safety counters just because of trying to find this)

running through thousands of cycles of debugging would drive me more crazy
so decided to re-write the ai avoiding coroutines and nested enumerators
need to find a more manageable way of doing ai anyway

 

thank you for the tip
when i tried that i didn't get expected behavior so i just thought it wasn't supported

for example after breaking getting an error, and clicking continue it doesn't continue
and i get "No compatible code running"

 

and then when i try to step, "Unable to step. Array subscript out of range."

I didn't read this the first time i checked (under the title "No compatible code running")

"The selected debug engine does not support any code executing on the current thread (e.g. only native runtime code is executing"

 

So is breaking on a hang supported? and in my case its just because i'm breaking on unity engine code?

i have no native dlls in my project

 

That's awesome! Thank You,
Yes, Visual Studio

how do i break using a native debugger ?

 

Code (CSharp):

1. >    ntdll.dll!00007fff37b704c2()    Unknown
2.      mono.dll!free(void * pBlock) Line 51    C
3.      mono.dll!g_queue_pop_head(GQueue * queue) Line 48    C
4.      mono.dll!end_runtime_invoke(_MonoProfiler * prof, _MonoMethod * method) Line 3336    C
5.      mono.dll!mono_profiler_method_end_invoke(_MonoMethod * method) Line 440    C
6.      mono.dll!mono_runtime_invoke(_MonoMethod * method, void * obj, void * * params, MonoObject * * exc) Line 2629    C
7.      Unity.exe!scripting_method_invoke(struct ScriptingMethodMono,struct MonoObject *,struct ScriptingArguments &,struct MonoException * *)    Unknown
8.      Unity.exe!ScriptingInvocation::Invoke(struct MonoException * *,bool)    Unknown
9.      Unity.exe!Coroutine::ProcessCoroutineCurrent(void)    Unknown
10.      Unity.exe!Coroutine::Run(void)    Unknown
11.      Unity.exe!MonoBehaviour::CreateCoroutine(struct MonoObject *,struct ScriptingMethodMono)    Unknown
12.      Unity.exe!MonoBehaviour::StartCoroutineManaged2(struct MonoObject *)    Unknown
13.      Unity.exe!MonoBehaviour_CUSTOM_StartCoroutine_Auto(struct ReadOnlyScriptingObjectOfType<class MonoBehaviour>,struct MonoObject *)    Unknown
14.      00000000237d4e85()    Unknown
15.      0000000026b77400()    Unknown
16.      00000000214aa348()    Unknown
17.      00000000221f28d0()    Unknown
18.      0000000024de8260()    Unknown
19.      00000000318e2050()    Unknown
20.      0000000026b77400()    Unknown
21.      0000000004c40000()    Unknown
22.      000000000c8365a0()    Unknown
23.      000000000c8313f0()    Unknown
24.      00000000318e20a0()    Unknown
25.      0100000024de8260()    Unknown
26.      0000000024de8260()    Unknown
27.      00000000005fdc10()    Unknown
28.      00000000005fdb70()    Unknown
29.      00000000005fe340()    Unknown
30.      0000000004f367f8()    Unknown
31.      00000000005fe250()    Unknown
32.  

another one

Code (CSharp):

1. >    mono.dll!GC_mark_from(GC_ms_entry * mark_stack_top, GC_ms_entry * mark_stack, GC_ms_entry * mark_stack_limit) Line 761    C
2.      mono.dll!GC_mark_some_inner(...) Line 378    C
3.      mono.dll!GC_mark_some(char * cold_gc_frame) Line 478    C
4.      mono.dll!GC_stopped_mark(int(*)() stop_func) Line 607    C
5.      mono.dll!GC_try_to_collect_inner(int(*)() stop_func) Line 446    C
6.      mono.dll!GC_collect_or_expand(unsigned __int64 needed_blocks, int ignore_off_page) Line 1110    C
7.      mono.dll!GC_alloc_large(unsigned __int64 lw, int k, unsigned int flags) Line 60    C
8.      mono.dll!GC_generic_malloc(unsigned __int64 lb, int k) Line 204    C
9.      mono.dll!GC_malloc(unsigned __int64 lb) Line 311    C
10.      mono.dll!mono_array_new_specific(MonoVTable * vtable, unsigned int n) Line 4422    C
11.      000000000cdf0ad6()    Unknown
12.      000000000d51f480()    Unknown
13.      00000000005fdaf0()    Unknown
14.      0000000023d1f2c0()    Unknown
15.      mono.dll!mono_object_new_specific(MonoVTable * vtable) Line 3978    C
16.      000000000d51f480()    Unknown
17.      00000000005fdaf0()    Unknown
18.      00000000005fda50()    Unknown
19.      00000000005fe340()    Unknown
20.      000000000c6b67f8()    Unknown
21.      00000000005fe250()    Unknown
22.  

then exception on mono_security_core_clr_is_platform_image

 

um, step 1 quickwatch expression: "mono.dll!mono_pmip"
click add watch
and now there's a watch 1 panel, with the name mono.dll!mono_pmip, and value 0x00....

then what do i do?

 

and then

 

right so i've used it to see what the function names of stuff without names are, some return null some don't
but what am i looking for?

the call stack changes as i pause and continue

 

@Tautvydas Zilys THANK YOU!!!

knowing this is awesome
thank you for taking the time to explain it

my ai kept on trying to trace a route
nested coroutines with while loops can be hard to manage

 

Sooo what if I do all that, and instead of a function name coming out it just says "No type information is available for the function being called. If you are calling a function from another module, please qualify the function name with the name of the module containing it"?

http://puu.sh/pGFYS/806a338b43.png

I'm seriously at a loss as to what's going on. I hope someone still reads this.

edit: Further testing reveals ntWaitForSingleObject to be kind of halting everything?

http://puu.sh/pGGD2/8542211a41.png

edit2: it's stuck on an overhead?

http://puu.sh/pGWli/d1f1258c06.png

 

try this method

for me it pointed one below the problem method, (because the null that broke the loop happened there, which i didn't fully catch onto at first as i was mindlessly following the instructions)
very, very, useful

 

I've been looking for about 10 minutes, can't find a single CMP instruction even though all my debug boxes had been ticked while building.

Done, but now I don't have any pieces of unknown code anymore:

http://puu.sh/pHLXO/0e71b2bdd6.png

 

Ooooh I thought you meant forum thread. Right, how do I switch to the main thread?

 

Right, found it.

http://puu.sh/pI0qv/63449da720.png

I put a breaking point at the start of the PlayerLoop, let the hang run for a while, but it never reaches the PlayerLoop. What's next?

 

Yeah sure, I made a dump file and I'm uploading to mega as we speak. (It's half a GB).

I'm using 5.4.0B20

I'll start a conversation when it's done uploading.

Edit: started a conversation, hope you can figure it out!

 

Yup it's very easy to repeat: I Just have to boot the game a couple of times, and eventually it locks. If it doesn't after 15 seconds I try again. One in ~five times it hangs.

Profiling was enabled, but I believe it also happens Without any debugging enabled. I'll Have to double check to be certain about that though.

Should I send the entire project?

 

Yup, freeze also happens in the regular, non development build.