Joseph Ferano
2e203f64b8
The INSERTIONSORT crash, all three rulings (FIX.org 2026-09-20): - (bytes s) allocates a writable copy through the allocator surface — context or (bytes s a), StorageExhausted with retry, a registry note in dev builds (flan_bytes_dup, lowered like vec-new). (bytes-view s) is the old zero-cost reinterpret, renamed, read-only by convention; every in-repo reader swept over to it. (string b) unchanged. - String constants were already read-only on both backends at -O0; now pinned — bytes-copy.flan rows on LLVM/-O0/--x86, and dies_segv rows asserting the write-through-view trap on both backends. - A dev build installs a SIGSEGV/SIGBUS handler by the same dev-only constructor slot that arms the registry: one line naming the address and the innermost frame, then the trap-hook park — stopped, not dead, the daemon serving. No agent: message and re-raise. Release builds untouched. Pinned by trap_park over dev-segv.flan.
39 lines
1.5 KiB
Plaintext
39 lines
1.5 KiB
Plaintext
;;;; (bytes s) copies, (bytes-view s) aliases — the ruling from the
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;;;; INSERTIONSORT dogfooding session. The pin is the exact inverse of the
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;;;; old aliasing: a write through the copy leaves the original string
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;;;; printing unchanged, where the old (bytes s) either showed the write
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;;;; through or trapped, depending on where the string's storage was.
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(defvar frame Allocator)
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(defn main [] i32
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;; 1. The copy is writable and independent. Under the old reinterpret this
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;; second line printed ZNSERTIONSORT too (or the whole program died in
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;; .rodata) — the original staying itself is the whole of the change.
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(let [s "INSERTIONSORT"
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b (bytes s)]
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(set (at b 0) \Z)
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(println (string b)) ; ZNSERTIONSORT
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(println s)) ; INSERTIONSORT
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;; 2. A literal's copy is writable — the exact form that used to segfault
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;; at -O0 and silently do nothing at -O2.
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(let [b (bytes "hi")]
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(set (at b 0) \H)
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(println (string b))) ; Hi
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;; 3. The view still costs nothing and reads the string's own storage.
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(let [v (bytes-view "abc")]
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(println (len v)) ; 3
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(println (at v 2))) ; 99
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;; 4. (bytes s a) names the allocator, like (vec-new T a) and (clone v a):
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;; the copy's block comes from the arena and free-all reclaims it.
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(set frame (arena-new 4096))
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(let [b (bytes "arena" frame)]
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(set (at b 4) \A)
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(println (string b))) ; arenA
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(free-all frame)
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(arena-destroy frame)
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0)
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