[Issue 19601] Running -profile=gc when no gc is logged leaves old misleading file contents

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=19601

--- Comment #3 from hsteoh at quickfur.ath.cx ---
Ran into this today. Taken together with the other -profile=gc issues, this
makes -profile=gc extremely misleading. It fails to detect GC allocations via
druntime APIs, *and* fails to update profilegc.txt when no allocations happened
on that run, leaving stale data in the file (or fails to create the file at
all, making users wonder whether -profile=gc even had any effect).

At the very least it should create an empty file per run.

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