Payload captures no longer alias the original value#4454
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andrewrk merged 2 commits intoziglang:masterfrom Feb 14, 2020
Merged
Payload captures no longer alias the original value#4454andrewrk merged 2 commits intoziglang:masterfrom
andrewrk merged 2 commits intoziglang:masterfrom
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The payload doesn't alias anymore the same memory it comes from and is instead a fresh copy of the original object.
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Curious -- Do you know if LLVM only emits a copy in Release build modes when the capture was modified? |
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Nice work. |
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Ad discussed with Andrew in #4443 I've changed the behavior of
for/if/while/switchso that a "simple" capture (|v|) always creates a copy of the payload in a scope-local variable. If you need to modify the underlying memory just use a "ref" capture (|*v|).I've added a few tests to make sure this new behavior is respected and I've run the stage1/std test suite and I've not spotted any regression. That's possibly a sign of how nobody expected the capture to behave like it did :P or maybe everybody knew that and worked around it.
Closes #4361
Closes #2915