iOS 10.0: -[UILabel sizeThatFits:] may crash

Originator:raise.rescue
Number:rdar://28799281 Date Originated:17-Oct-2016 04:20 PM
Status:Open Resolved:
Product:Developer Tools Product Version:iOS 10.0
Classification:Crash/Hang/Data Loss Reproducible:Always
 
Summary:
-[UILabel sizeThatFits:] may crash for strings from several unicode pages and numberOfLines > 1, for example for the string 

@"Other notes unicodeपकतदगगदगरकयसुु्ीूबचकरल😝🤑🤗😏😗😛😎😴😷👍🏻👌🏼💆🏼‍♂️💆🏼‍♂️💇🏼👯‍♂️👯‍♂️🏃🏻‍♀️🚶🏻👯💃🏼💇🏼‍♂️🙍🏼रकतचजदययरररलفغعهننوااعتتلببزوو راللب بلبरतचदगुबकलुनम्पगूीहकरपिلات💇🏼💆🏼‍♂️"

Steps to Reproduce:
Start the attached project on an iOS 10 Simulator / iOS 10 iPad 

Expected Results:
No crash.

Actual Results:
The app crashes in CFStringCreateCopy.

Regression:
DId not happen in iOS 9.3

Notes:
No known workaround (except for reducing the number of lines to 1, which is impractical in most cases)

Comments


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