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--- sd:tinyc_developer_diary [2026/04/19 14:39] – appledog
+++ sd:tinyc_developer_diary [2026/04/20 04:58] (current) – appledog
@@ Line 810: / Line 810: @@
 == A classic clobbering bug
-To do forward declarations, the code used two special global variables to pass information between two parts of the code: KIND and ENTRY. KIND told the code whether the function was already defined (kind 2) or just forward-declared (kind 4). But the same function that identified a function also identified the arguments. So during the parsing of the arguments the function type was being over-written. And therefore it's address was not being back-patched in the patch loop chain.
+To do forward declarations, the code used two special global variables to pass information between two parts of the code: KIND and ENTRY. KIND told the code whether the function was already defined (kind 2) or just forward-declared (kind 4). But the same part of the parser that identified a function was being recursively called on the arguments of that function. So during the parsing of the arguments the function type was being over-written. And therefore it's address was not being back-patched in the patch loop chain.
-Now I know this sounds simple when I lay it out, but this took me 10 hours to fix. It's just a classic clobber-bug but it's a sign this code is starting to weigh me down. I just want to write some games. I don't understand why this has to be so hard.
+Now I know this sounds simple when I lay it out, but this took me 10 hours to fix. It's just a classic clobber-bug but it's a sign this code is starting to weigh me down. I just want to write some games. I don't understand why this has to be so hard. But even after all this I am pretty sure it is easier than writing a GCC or LLVM back end.
+== Everything in bank 0!
+I was such a fool to make the symbol table 16 bit. Now everything has to be in bank 0. But there's not enough space for self-hosting. The code AND the compiled code both are over 32k.
+I have a plan. What if we put the output ~2k before the source code? The tokenizer and other things seem to output less bytes than source code, so it should work.
+So if HERE grows into the source area as source gets consumed, we can theoretically use up to 48KB for source code AND compiled code. This requires HERE to stay behind SRC at all times. It destroys the code as it compiles, but that's okay. The two pointers march through the memory, with HERE chasing SRC. The only problem is if the emitter somehow catches up with the source code pointer.
+At this point I am very close to just rewriting the symbol table to be 32 bit. I mean this is already an insane asylum as it is, but, how hard could rewriting the emitters possibly be? :)
+== Rewriting the symbol table
+I guess I'm about to find out how hard it can be.