Don’t explicitly change GetMem(0) to GetMem(1), it works anyway.

Correct me, but while the user code might have relied on the fact that GetMem(0) returns non-nil, including at least one part of the compiler itself ({$define macro :=} allocates its tmacro.buftext with GetMem(0), and then assigned(tmacro.buftext) is used to discriminate macros with values), there is no need to explicitly ensure that, GetMem(0) would already go the same way as GetMem(1).

Patch: getmem0.patch.