Data race detected when compiling app under TSan

[iMostfa]

Hello Team,






running the app under TSan results in the following data race, i can't verify if it's causing crashes/inconstancies on prod, but in general data races could cause issues.

most likely we need a synchronised NSDictionary

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�[1m�[31mWARNING: ThreadSanitizer: data race (pid=69950)
�[1m�[0m�[1m�[34m  Read of size 8 at 0x000158142c50 by thread T13:
�[1m�[0m
    #0 __54-[NSDictionary(MPCaseInsensitive) caseInsensitiveKey:]_block_invoke NSDictionary+MPCaseInsensitive.m:16 (mParticle_Apple_SDK:arm64+0x1f53d4)
    #1 __NSARRAY_IS_CALLING_OUT_TO_A_BLOCK__ <null>:584394248 (CoreFoundation:arm64+0x91c04)
    #2 _dispatch_client_callout2 <null>:584394248 (libdispatch.dylib:arm64+0x39b0)

�[1m�[34m  Previous write of size 8 at 0x000158142c50 by thread T7:
�[1m�[0m    #0 __copy_helper_block_e8_32s40r mParticle.m (mParticle_Apple_SDK:arm64+0x33620)
    #1 _call_copy_helpers_excp <null>:584394248 (libsystem_blocks.dylib:arm64+0x10b4)
    #2 __NSCollectionHandleConcurrentEnumerationIfSpecified <null>:584394248 (CoreFoundation:arm64+0x15157c)
    #3 -[MPBackendController setUserAttributeChange:completionHandler:] MPBackendController.m:544 (mParticle_Apple_SDK:arm64+0x57a0c)
    #4 -[MPBackendController setUserAttribute:value:timestamp:completionHandler:] MPBackendController.m:1726 (mParticle_Apple_SDK:arm64+0x6b014)
    #5 __40-[MParticleUser setUserAttribute:value:]_block_invoke MParticleUser.m:286 (mParticle_Apple_SDK:arm64+0x425a8)
    #6 __tsan::invoke_and_release_block(void*) <null>:584394248 (libclang_rt.tsan_iossim_dynamic.dylib:arm64+0x77ee0)
    #7 _dispatch_client_callout <null>:584394248 (libdispatch.dylib:arm64+0x3974)

�[1m�[32m  Location is heap block of size 48 at 0x000158142c30 allocated by thread T7:
�[1m�[0m    #0 malloc <null>:584394248 (libclang_rt.tsan_iossim_dynamic.dylib:arm64+0x4fa48)
    #1 _malloc_type_malloc_outlined <null>:584394248 (libsystem_malloc.dylib:arm64+0xf3ec)
    #2 __NSCollectionHandleConcurrentEnumerationIfSpecified <null>:584394248 (CoreFoundation:arm64+0x15157c)
    #3 -[MPBackendController setUserAttributeChange:completionHandler:] MPBackendController.m:544 (mParticle_Apple_SDK:arm64+0x57a0c)
    #4 -[MPBackendController setUserAttribute:value:timestamp:completionHandler:] MPBackendController.m:1726 (mParticle_Apple_SDK:arm64+0x6b014)
    #5 __40-[MParticleUser setUserAttribute:value:]_block_invoke MParticleUser.m:286 (mParticle_Apple_SDK:arm64+0x425a8)
    #6 __tsan::invoke_and_release_block(void*) <null>:584394248 (libclang_rt.tsan_iossim_dynamic.dylib:arm64+0x77ee0)
    #7 _dispatch_client_callout <null>:584394248 (libdispatch.dylib:arm64+0x3974)

�[1m�[36m  Thread T13 (tid=12827004, running) is a GCD worker thread

�[1m�[0m�[1m�[36m  Thread T7 (tid=12826816, running) is a GCD worker thread

�[1m�[0mSUMMARY: ThreadSanitizer: data race NSDictionary+MPCaseInsensitive.m:16 in __54-[NSDictionary(MPCaseInsensitive) caseInsensitiveKey:]_block_invoke
==================