Merging r231839:

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r231839 | ericwf | 2015-03-10 13:43:34 -0700 (Tue, 10 Mar 2015) | 11 lines

[libcxx] Fix PR21580 - Undefined behavior in readEncodedPointer()

Summary: This patch fixes a bug in `readEncodedPointer()` where it would read from memory that was not suitably aligned. This patch fixes it by using memcpy.

Reviewers: danalbert, echristo, compnerd, mclow.lists

Reviewed By: compnerd, mclow.lists

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D8179
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llvm-svn: 236860