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, 3 insertions, 0 deletions

diff --git a/053recipe_header.cc b/053recipe_header.cc
index 057234f9..b948ce61 100644
--- a/053recipe_header.cc
+++ b/053recipe_header.cc
@@ -207,6 +207,9 @@ case NEXT_INGREDIENT_WITHOUT_TYPECHECKING: {
   if (current_call().next_ingredient_to_process < SIZE(current_call().ingredient_atoms)) {
     products.push_back(
         current_call().ingredient_atoms.at(current_call().next_ingredient_to_process));
+    if (is_mu_scalar(current_call().ingredients.at(current_call().next_ingredient_to_process))
+        && is_mu_address(current_instruction().products.at(0)))
+      products.at(0).insert(products.at(0).begin(), /*alloc id*/0);
     assert(SIZE(products) == 1);  products.resize(2);  // push a new vector
     products.at(1).push_back(1);
     ++current_call().next_ingredient_to_process;