# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1232231117 -3600
# Node ID 9abe641af4e62799415a7828bb544e4e5e1c83c0
# Parent  d213a26b1846790bd50dc66510f161691b15bff2
Make unused name and object removal more conservative, avoiding issues of
module/class attributes and non-class/function objects being removed and then
being requested in code generation.
Ensure the registration of constant-related objects in order to prevent their
removal.

diff -r d213a26b1846 -r 9abe641af4e6 micropython/inspect.py
--- a/micropython/inspect.py	Sat Jan 17 22:33:19 2009 +0100
+++ b/micropython/inspect.py	Sat Jan 17 23:25:17 2009 +0100
@@ -146,17 +146,12 @@
 
             if self.should_optimise_unused_objects():
 
-                # Remove unused names.
-
-                if name not in self.importer.names_used:
-                    del self[name]
-
                 # Remove entries for unreferenced objects.
                 # This, due to the nature of the referenced attribute, assumes
                 # that only explicitly mentioned classes and functions are
                 # employed in the final program.
 
-                elif isinstance(value, Attr):
+                if isinstance(value, Attr):
                     attr_value = value.value
 
                     # Only remove entries for classes and functions, not methods.
@@ -195,16 +190,15 @@
                 if isinstance(obj, Class):
                     for name, attr in obj.class_attributes().items():
 
-                        if name not in self.importer.names_used:
-                            del obj[name]
+                        # Methods can only be deleted if they are the only
+                        # assigned object to the class and are unreferenced.
 
-                            # Methods can only be deleted if they are the only
-                            # assigned object to the class and are unreferenced.
+                        if name not in self.importer.names_used and \
+                            attr.assignments == 1 and isinstance(attr.value, Function) and \
+                            attr.value.is_method() and not attr.value.referenced:
 
-                            if attr.assignments == 1 and isinstance(attr.value, Function) and \
-                                attr.value.is_method() and not attr.value.referenced:
-
-                                self.all_objects.remove(attr.value)
+                            self.all_objects.remove(attr.value)
+                            del obj[name]
 
     def finalise(self):
 
@@ -529,6 +523,16 @@
         return self.OP(node)
 
     def visitConst(self, node):
+
+        # Accounting.
+
+        name = node.value.__class__.__name__
+        if self.builtins is not None and self.builtins.has_key(name):
+            attr = self.builtins[name]
+            attr.set_referenced()
+
+        # Register the constant, if necessary, returning the resulting object.
+
         return self.importer.make_constant(node.value)
 
     visitContinue = NOP
diff -r d213a26b1846 -r 9abe641af4e6 tests/attributes.py
--- a/tests/attributes.py	Sat Jan 17 22:33:19 2009 +0100
+++ b/tests/attributes.py	Sat Jan 17 23:25:17 2009 +0100
@@ -2,6 +2,7 @@
 
 class C:
     clsattr = 123
+    clsattr2 = 456
 
     def __init__(self, value):
         self.instattr = value