I just discovered something interesting: Building Firefox with `-O3 -lfto` (and using LLVM 21 tools) disables copy propagation. The builds take more than twice as long as "normal" builds, but they aren't effected by the copy propagation bug. `-flto` turns on "link time optimization".
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I just discovered something interesting: Building Firefox with `-O3 -flto` (and using LLVM 21 tools) disables copy propagation. The builds take more than twice as long as "normal" builds, but they aren't effected by the copy propagation bug. `-flto` turns on "link time optimization".