[bug #33362] Segfault with let and a case-lambda that calls another case

[Stefan Israelsson Tampe <INVALID.NOREPLY@gnu.org>]

Follow-up Comment #1, bug #33362 (project guile):

Entering the offending code in a function, f,  and disassembled it 
leading to, 
> ,x f
...
Disassembly of #<procedure t (x) | (x y)>:

   0    (br-if-nargs-ne 0 1 :L997)      ;; -> 21
   6    (reserve-locals 0 1)            
   9    (local-ref 0)                   ;; `x'
  11    (object-ref 1)                  ;; y  
  13    (local-set 1)                   
  15    (local-set 0)                   ;; `x'
  17    (br :L998)                      ;; -> 23
  21    (assert-nargs-ee/locals 2)     
...

This results in error behavior as stated. Now increasing the reservation by
one in (reserve-locals 0 1) with a hex editor fixes the problem and the object
code runs just fine. So probably when y is used in the case lambda with fewer
used arguments the compiler misses the number of reservations of the stack
that is needed. So later when the code calls a function and stack space is
needed some undefined behavior results e.g. a crash.

Solution?
The problem is in the tree-il compilation code. The allocation
of number of locals needs to be adjusted for the self referential parts.
consider to store the suggested value, v, 
as (alloc new v ncarg). Then when compiling the a self referential call with
narg elements. Then we need to update acording to: 

  new = max(new,v + max(0,narg - ncarg))

Safest is to parse the tree-il subcode for self referentials
and update the local-variables and argument stack layout acordingly. 

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