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Fixed in 2018.1.X

Fixed in 5.6.X, 2017.1.X, 2017.2.X, 2017.3.X, 2017.4.X



Found in


Issue ID




"Assertion failed: TLS Allocator ALLOC_TEMP_THREAD..." error is shown after building the project for iOS'



To reproduce:

1. Create a new project
2. Build it for iOS
3. Observe the console after the build has finished

Expected: no assertion errors are shown after building the project for iOS

Reproduced in 5.6.0a2, 5.6.1p4, 2017.1.0b8, 2017.2.0a4
Did not reproduced in 5.5.4f1, 5.6.0a1
Regression introduced in 5.6.0a2
Not reproducible in 2017.3.0a3

Comments (130)

  1. allenk00

    Nov 14, 2017 09:00

    same problem in 2017.2.0f3

  2. GilCat

    Nov 11, 2017 13:15

    Same problem in Unity 2017.3.0b9

  3. RKSW

    Nov 10, 2017 20:57

    For me, this is more an irritant than anything else. It constantly produces output to the error window adding clutter to the info I need during development.

  4. MilesRenatus

    Nov 08, 2017 15:33

    Still having this issue in 2017.3.0b8 on Windows 10. Computer specs in case it is relevant: Intel i5-6300HQ, Nvidia GTX 950M, 8GB DDR4 RAM.

  5. maiko

    Nov 08, 2017 11:43

    This is still happening for me in 2017.3.0b8. I am developing in Android.

  6. gldio

    Nov 07, 2017 14:57

    same problem in version 2017.2.0f3 in win10. only occures after ios build and the fix is to restart unity.


    Nov 06, 2017 01:01

    This is also appearing in 2017.3.0b6.
    It seems to occur MORE frequently when the build window is open. The project is set to iOS.
    The error seems to be generated whenever the mouse passes into and out of a window/tab. Therefore, moving the mouse normally can fill the error log with these logs and errors. It seems to occur only after the first Build to iOS. After that, the error message are constant.
    I have a dual monitor setup. It seems even worse when the build window is on the second monitor, but that may simply be due to the fact the mouse pointer is entering and exiting the Unity windows more often.

  8. KillStone1997

    Oct 27, 2017 18:36

    Having the same issue (on Windows, after updated unity to 2017.2.0f3).

  9. bfreesePrsonas

    Oct 26, 2017 17:37

    I found this in 2017.3.0b3. It was reproduced in a simple base scene as ships with unity building to iOS.

    Assertion failed: TLS Allocator ALLOC_TEMP_THREAD, underlying allocator ALLOC_TEMP_THREAD has unfreed allocations, size 132

  10. Mazoin

    Oct 17, 2017 13:05

    same problem in 2017.2.0f3

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