fanquake 31c9987976

Merge #20447: depends: Patch qt_intersect_spans to avoid non-deterministic behavior in LLVM 8 ...

8f7d1b39efbe65ab2747c593cc3560d4a449a333 Fix QPainter non-determinism on macOS (Andrew Chow)

Pull request description:

  Aplies a patch to Qt that fixes the non-determinism by modifying Qt. The source of the non-determinism is how LLVM 8 optimizes qt_intersect_spans when compiling. The particular optimization that seems to be causing the problems is that a temp variable is being added for spans->y. For some reason, when it does this, it chooses different instructions to use when making that variable. We bypass this problem by patching qt_intersect_spans to always make and use this local variable.

  Potential alternative to #20436 and #20440

ACKs for top commit:
  hebasto:
    re-ACK 8f7d1b39efbe65ab2747c593cc3560d4a449a333 ~for merging into the 0.21 branch, but [not into the master](https://github.com/bitcoin/bitcoin/pull/20454) branch.~
  fanquake:
    ACK 8f7d1b39efbe65ab2747c593cc3560d4a449a333

Tree-SHA512: b0d00a77643554021736524fb64611462ef2ec849a220543c12d99edb0f52f2e8128d2cc61fa82176b7e13b294574774a92d6b649badf8b7630c6d6a7e70ce10

2020-11-24 21:12:02 +08:00

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bdb

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fontconfig

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libevent

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miniupnpc

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native_cctools

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native_cdrkit

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native_libdmg-hfsplus

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qt

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zeromq

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