TrueBrain opened the ticket and wrote:

Latest revision, and below (including 0.5.x) have a simple way to crash a remote server:

remove CMD_AUTO from a command, say, BuildHQ (it has to be a building command, and it has to build 2 tiles or more at once), remove the assert checking res == res2 in command.cpp, and join a server... build on a 2 tile structure (stadium, tunnel, ...), and you have a nice assert on the server (if enabled of course).

The problem is simple, but hard to solve I am afraid:

LANDSCAPE_CLEAR is called in test-phase and given back cost N for removing the structure + cleaning land on both tiles of the building. So it costs you N*2. While in reality it will only cost you N. So the assert happens, and the server is down.

2 possible ways to solve it: fix LANDSCAPE_CLEAR to understand 2 tile structures (hard, if not impossible). Other way: force CMD_AUTO server-side.

Reported version: trunk
Operating system: All

This issue was imported from FlySpray: https://bugs.openttd.org/task/1179