__attribute__((noescape)) doesn't seem to work in Objective-C

Number:rdar://19989922 Date Originated:27-Feb-2015 02:08 PM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 6.3 (6D532l) / OS X 10.10.2 (14C109)
Classification:Other Bug Reproducible:Always
The Xcode 6.3 beta 2 release notes describe a new attribute "noescape," which specifies that a given block argument won't be captured and escape the receiving method. However, this attribute fails to produce a warning in pure Objective-C code when the method does in fact cause the given block to escape.

Steps to Reproduce:
1. Open the attached sample project
2. Build it

Expected Results:
-invokeBlockLater: produces a warning because the given block, despite being declared with __attribute__((noescape)), is captured in both the lastLaterBlock and the laterBlocks properties.

Actual Results:
No warning is produced.

Sample project at https://github.com/lithium3141/NoescapeTest


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