Merging r196802:
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r196802 | chandlerc | 2013-12-09 11:25:51 -0800 (Mon, 09 Dec 2013) | 11 lines

Revert three patches which were committed without explicit contribution
by their authors.

This may break builds where others added code relying on these patches,
but please *do not* revert this commit. Instead, we will prepare patches
which fix the failures.

Reverts the following commits:
r168306: "[asan] support x32 mode in the fast stack unwinder. Patch by H.J. Lu"
r168356: "[asan] more support for powerpc, patch by Peter Bergner"
r196489: "[sanitizer] fix the ppc32 build (patch by Jakub Jelinek)"
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