legoland

A matching decompilation of legoland.exe (x86 Windows, built with Microsoft Visual C++ 6.0), in the style of the LEGO Island decompilation: ordinary C is compiled with the original MSVC6 toolchain and verified function-by-function against the original binary with reccmp. Addresses and relocations are normalized away, so the recompiled binary does not need to reproduce the original's layout — a function "matches" when its compiled bytes equal the original's.

This repo is self-contained: the MSVC6 compiler and its support DLLs are downloaded by setup.py into a gitignored toolchain/. The wibo PE loader must be installed and on PATH. No proprietary binaries are committed.

Quick start

uv run setup.py          # download MSVC6 + DLLs into toolchain/
cmake --preset msvc6     # configure (uses cmake/msvc6-toolchain.cmake)
cmake --build build      # build legoland.exe + PDB (all 99 TUs)
./tools/verify           # per-function match % vs the original
./tools/verify --html report.html        # searchable HTML report
./tools/verify -v 0x004015c0             # asm diff for one function

tools/verify runs reccmp, whose bundled cvdump.exe (PDB reader) is also executed through wibo (via the tools/wine shim).

Layout

path	what
src/legoland/*.c	one .c per TU (99 of them); functions annotated // FUNCTION: LEGOLAND 0x...
src/legoland/legoland.h	shared forward declarations + globals + the STUB() marker
cmake/	CMake toolchain file driving MSVC6 through wibo
setup.py	downloads the toolchain (hardcoded, pinned URLs)
external/legoland.exe	the original binary (match target)
reccmp-project.yml	reccmp configuration

Conventions

• Unmatched functions carry a STUB(); body. Find remaining work with grep -rn 'STUB()' src/.
• Matched functions have a real body that compiles (with MSVC6) to bytes identical to the original.
• Each function is tagged with its original virtual address; reccmp matches by that address via the build's PDB.

The function inventory (name → offset → TU) comes from ghidra/functions.csv in the parent project.