The reload path had never seen a restart-case or a handler-bind: the
acceptance table's dev build proves whole-program codegen with cells, but not
Emit.redefinition, where the callees are declares or cell loads and the restart
frame is an alloca in a module the process was not built with. Driving it found
a hole step 1 left - a lifted clause was numbered by its position in the whole
program's lifted list, so the name was neither stable against an unrelated
handler-bind being added nor attributable to the function it came out of, and
redefining a function that established a handler died in llc with an undefined
value.
A clause is now named after its parent - handler/step/0/Missing - and carries
Tast.fn.fparent, which is what lets a redefinition module emit the clauses
belonging to the bodies it is replacing and nothing else. They are hidden for
the same reason a redefined body is: taking the address of an interposable
symbol would resolve to the host's copy, so the module would install the very
handler it was replacing. A clause is reached by address from its parent and
from nowhere else, so it is kept out of the cell and registry machinery
entirely rather than given a slot nobody uses.
test_dev.ml now sends a third evaluation: step redefined to a restart-case
whose frame is an alloca in the new module, whose guarded call goes through the
host's cell, and whose transfer starts in a handler and crosses probe, which
the host was compiled with. The transcript's fourth line is the clause's value.
Joseph Ferano
2fadf82e23