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.
bounds.flan covers this already and the x86 survey cannot see it: the
program picks its case out of (at args 1) and survey.sh runs everything
with no arguments, so re-gating x86's lo <= hi would have failed
nothing. This probe reaches the reversed slice on its own, through
(len args) so that neither optimiser can fold the branch and the checker
has no literal to object to. It matches under the default sweep and
under SURVEY_FLAGS=--no-bounds-checks, which is the claim.
Also records what the same reading turned up and did not fix: x86 still
reports a negative slice-from-ptr promise through flan_slice_error, so
the two backends print different sentences for it, and no corpus program
reaches that case without arguments.
