Hermit: Unify std::env::args
with Unix
#139711
Open
+9
−40
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The only differences between these implementations of
std::env::args
are that Unix uses relaxed ordering, but Hermit uses acquire/release, and Unix truncatesargv
at the first null pointer, but Hermit doesn't. Since Hermit aims for Unix compatibility, unify it with Unix.The atomic orderings were established in #74006 (cc @euclio) for Unix and #100579 (cc @joboet) for Hermit and, before those, they used mutexes and non-atomic statics. I think the difference in orderings is simply from them being changed at different times. The commented explanation for using acquire/release for Hermit is “to broadcast writes by the OS”. I'm not experienced enough with atomics to accurately judge, but I think acquire/release is stronger than needed. Either way, they should match.
Truncating at the first null pointer seems desirable, though I don't know whether it is necessary in practice on Hermit.
cc @mkroening @stlankes for Hermit