How to fix "Too Many Symbols files" warning

At AppStore Connect upload, a binary can generate a warning that warns you that some symbols files in the package does not have any corresponding slice.

ITMS-90381: Too many symbol files - These symbols have no corresponding slice in any binary [A84179A8-B2D7-3124-8D9B-7059AEE7ABC0.symbols, 155C0CE8-A9A9-3A04-A081-1F50BAA50348.symbols, D27E0F7B-E1A5-3EFA-A498-091223C948BF.symbols, E323D695-5138-3257-8020-BBCBE5223019.symbols, 1EE5BCD4-DF20-3F09-ACFD-CAB2D16BF5F2.symbols, 3ED39453-629A-3B8A-98F5-FFCBAEF1DD40.symbols, DAC745EF-6DA6-3FFE-9DFA-D9867B6219D4.symbols, 680A0BCB-1E35-3EF5-BD25-0EA7D6D68E27.symbols, 90CE7BAB-4D86-366B-BACF-4595713CBFE7.symbols, 2CAD9337-9FDD-372E-82B9-F7BB5FA87515.symbols, 8B03EE45-11F7-3316-B30A-B8B74AE0E57E.symbols, 24F449F3-CCD2-3B96-9FF5-2316DCD09A5F.symbols, 784CE309-635C-3433-968B-12E7BAA38B2A.symbols, ED643F40-D42A-32DD-88F2-19A0998D9398.symbols, 58928546-4914-3975-9E5C-D197E5B0CDF3.symbols, 6D8DE815-CB5B-32A4-B73E-C92FC43BF59F.symbols, 19A827CD-D09F-3E98-A4F9-6822F3EA489F.symbols, FB1AAF1A-9F6A-316B-A76E-F46336C715FB.symbols].

Even if it's not mandatory to correct and probably harmless, it is good thing to fix it since it can reduce drastically the generated package size.

Usually, that's because you're building your app for armv7 and minimum deployment target superior or equal to iOS 11.0. In this case, removing armv7 for the VALID_ARCHS/ARCHS lists does the trick.

Otherwise here's how to fix it :

https://stackoverflow.com/questions/25755240/too-many-symbol-files-after-successfully-submitting-my-apps