clear descriptor table in __wasilibc_reset_preopens#776
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dicej merged 1 commit intoWebAssembly:mainfrom Mar 23, 2026
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clear descriptor table in __wasilibc_reset_preopens#776dicej merged 1 commit intoWebAssembly:mainfrom
__wasilibc_reset_preopens#776dicej merged 1 commit intoWebAssembly:mainfrom
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The original intention of `__wasilibc_reset_preopens` was to clear the stdio state as the last step of Wizer-style pre-initialization since none of the handles would be valid when the snapshot is resumed. In earlier versions of `wasi-libc`, which didn't have native p2 or p3 support for stdio or file I/O, resetting the WASIp1 state was sufficient; the `wasi_snapshot_preview1` adapter took care of emulating p1 in terms of p2. However, now that `wasi-libc` has native support for p2 and p3, we need to also reset the descriptor table. At this point, the name `__wasilibc_reset_preopens` is a bit misleading for p2+ since we're clearing more than just the preopens, but changing the name would break tools which use it, so probably not worth the trouble.
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The original intention of
__wasilibc_reset_preopenswas to clear the stdio state as the last step of Wizer-style pre-initialization since none of the handles would be valid when the snapshot is resumed. In earlier versions ofwasi-libc, which didn't have native p2 or p3 support for stdio or file I/O, resetting the WASIp1 state was sufficient; thewasi_snapshot_preview1adapter took care of emulating p1 in terms of p2. However, now thatwasi-libchas native support for p2 and p3, we need to also reset the descriptor table.At this point, the name
__wasilibc_reset_preopensis a bit misleading for p2+ since we're clearing more than just the preopens, but changing the name would break tools which use it, so probably not worth the trouble.