[PATCH] D67774: [Mangle] Add flag to asm labels to disable '\01' prefixing

[John McCall via cfe-commits]

On Tue, Jan 7, 2020 at 1:44 PM Aaron Ballman via Phabricator
<reviews at reviews.llvm.org> wrote:
> aaron.ballman added inline comments.
>
>
> ================
> Comment at: cfe/trunk/lib/AST/Mangle.cpp:127
> +    // do not add a "\01" prefix.
> +    if (!ALA->getIsLiteralLabel() || ALA->getLabel().startswith("llvm.")) {
> +      Out << ALA->getLabel();
> ----------------
> Sorry to dredge up an old review, but I recently ran into a bug in this area and am not certain of how to fix it. What should happen if the asm label is a literal which is empty?

The problems here are unique to empty labels, right?  Can we just
diagnose this as an error?  Is this bug occurring with real code, or
is LLDB constructing something bizarre?

John.