4257 - abortive attempt at safe fat pointers

I've been working on this slowly over several weeks, but it's too hard
to support 0 as the null value for addresses. I constantly have to add
exceptions for scalar value corresponding to an address type (now
occupying 2 locations). The final straw is the test for 'reload':

  x:num <- reload text

'reload' returns an address. But there's no way to know that for
arbitrary instructions.

New plan: let's put this off for a bit and first create support for
literals. Then use 'null' instead of '0' for addresses everywhere. Then
it'll be easy to just change what 'null' means.

1 files changed, 9 insertions, 8 deletions

diff --git a/074wait.cc b/074wait.cc
index eb17c8aa..47bbb0cc 100644
--- a/074wait.cc
+++ b/074wait.cc
@@ -262,22 +262,23 @@ def main [
 :(scenario get_location_indirect)
 # 'get-location' can read from container address
 def main [
-  1:num <- copy 10
-  10:num <- copy 34
-  11:num <- copy 35
+  1:&:point <- copy 10/unsafe
+  # skip alloc id
+  11:num <- copy 34
+  12:num <- copy 35
   4:location <- get-location 1:&:point/lookup, 0:offset
 ]
-+mem: storing 10 in location 4
++mem: storing 11 in location 4
 
 :(scenario get_location_indirect_2)
 def main [
-  1:num <- copy 10
-  10:num <- copy 34
-  11:num <- copy 35
+  1:&:point <- copy 10/unsafe
+  11:num <- copy 34
+  12:num <- copy 35
   4:&:num <- copy 20/unsafe
   4:&:location/lookup <- get-location 1:&:point/lookup, 0:offset
 ]
-+mem: storing 10 in location 20
++mem: storing 11 in location 21
 
 //: allow waiting on a routine to complete