Initialized allocate in assembler

RCPU/assembler/parser.py

@@ -18,7 +18,7 @@ def parse_resource(line):
         size = int(parts[2])
         if size < 1:
             raise utils.AssemblerException("Size of allocated memory too small: {}".format(line))
-        return parts[0], '_' * (size - 1)
+        return parts[0], '\0' * (size - 1)
     else:
         raise utils.AssemblerException("Unknown resource type in .data: {}".format(line))
 

docs/assembly_files.md

@@ -25,7 +25,7 @@ The `.data` section contains data like strings and constants. There are three
 - Allocations look like `.alloc allocate 5`: `.alloc` is the name of the label and
  `5` is the size of the buffer that will be allocated when the binary is assembled.
  Memory will only be allocated if the label is used in the `.text` section.
- The allocated memory will be "dirty", so you can't count on it having a certain value.
+ The allocated memory will be initialized with zeroes.
 
 ### .text section
 The `.text` section contains an entrypoint, instructions and labels: