我尝试在异步线程中绘制UILabel内容，并遇到一些崩溃，Crashed: async_display.queue :: NSOperation 0x17444b5e0 (QOS: USER_INTERACTIVE)
EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000000000058，下面是示例代码：
- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx {
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
NSLayoutManager *layoutManager = [NSLayoutManager new];
layoutManager.usesFontLeading = NO;
NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:text];
[textStorage addLayoutManager:layoutManager];
NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:contentSize];
textContainer.lineFragmentPadding = 0;
textContainer.maximumNumberOfLines = 0;
[layoutManager addTextContainer:textContainer];
[layoutManager ensureLayoutForTextContainer:textContainer];
CGPoint glyphsPosition = CGPointZero;
CGRect textBounds = [layoutManager usedRectForTextContainer:textContainer];
UIGraphicsBeginImageContextWithOptions(contentSize, NO, 0.0);
NSRange glyphRange = [layoutManager glyphRangeForTextContainer:textContainer];
[layoutManager drawBackgroundForGlyphRange:glyphRange atPoint:glyphsPosition];
[layoutManager drawGlyphsForGlyphRange:glyphRange atPoint:glyphsPosition];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
});
}
在[layoutManager ensureLayoutForTextContainer:textContainer];行崩溃，崩溃信息：
0 UIFoundation 0x187486768 -[NSATSLineFragment getTypographicLineHeight:baselineOffset:leading:] + 116
1 UIFoundation 0x18747d1e0 -[NSATSTypesetter _layoutLineFragmentStartingWithGlyphAtIndex:characterIndex:atPoint:renderingContext:] + 2392
2 UIFoundation 0x18747e758 -[NSATSTypesetter layoutParagraphAtPoint:] + 160
3 UIFoundation 0x1874d4b34 -[NSTypesetter _layoutGlyphsInLayoutManager:startingAtGlyphIndex:maxNumberOfLineFragments:maxCharacterIndex:nextGlyphIndex:nextCharacterIndex:] + 2948
4 UIFoundation 0x1874d5cd8 -[NSTypesetter layoutCharactersInRange:forLayoutManager:maximumNumberOfLineFragments:] + 244
5 UIFoundation 0x18747f1b8 -[NSATSTypesetter layoutCharactersInRange:forLayoutManager:maximumNumberOfLineFragments:] + 448
6 UIFoundation 0x18746b2ec -[NSLayoutManager(NSPrivate) _fillLayoutHoleForCharacterRange:desiredNumberOfLines:isSoft:] + 1116
7 UIFoundation 0x18746cde0 -[NSLayoutManager(NSPrivate) _fillLayoutHoleAtIndex:desiredNumberOfLines:] + 196
8 UIFoundation 0x187479a94 _NSFastFillAllLayoutHolesUpToEndOfContainerForGlyphIndex + 1252
9 UIFoundation 0x1874a2100 -[NSLayoutManager ensureLayoutForTextContainer:] + 380
10 project 0x10056d384 __36-[AsyncDisplayLabel displayBlock]_block_invoke (ESPAsyncDisplayLabel.m:112)
11 project 0x10056db4c __29-[AsyncLayer asyncDisplay]_block_invoke.73 (ESPAsyncLayer.m:93)
我尝试使用pthread_mutex_t锁定NSTextKit init，但总是遇到崩溃......