Miscompilation of printstring at high optimization levels about tinygo HOT 6 CLOSED

Just confirming this is still an issue with the latest master branch. Was not sure with all of the core changes.

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I plan to look into it once I'm on a stable LLVM version. It is possible this is a bug in LLVM.

What I've found last time I experimented with it, is that it is a specific combination of a branch depending on a volatile variable, print, and time.Sleep(). Note that something like:

println("foo", uint16(5))

is turned into this:

runtime.printstring("foo")
runtime.printspace()
runtime.printuint16(5)
runtime.printnl()

EDIT: if you manage to reproduce this on a desktop computer, that would make finding the bug much easier (with bugpoint).

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Tested on stable LLVM, the issue is still present.

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It looks like I made a mistake while testing. I cannot reproduce it now (on stable LLVM) so it looks like a bug in LLVM that was fixed before the release.
@deadprogram can you try whether it is still present?

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Good news here, I also can no longer reproduce on latest LLVM. Seems you are correct, this must have been addressed upstream. Seems like it can ne closed now.

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Glad to hear, and thanks for testing!
So this is why I wasn't putting much time in it ;) I already suspected a LLVM bug as it happened during an optimization pass.

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