[lld] [llvm] [Symbolizer] Support for Missing Line Numbers. (PR #82240)

[David Blaikie via llvm-commits]

https://github.com/dwblaikie commented:

Is it suitable to give the user the choice between forwards and backwards propagation? How would someone decide which is right for them?

That this can propagate past basic block, or even function boundaries seems pretty problematic - since the answer could then change depending on code layout, or could give someone a totally wrong function (ask me about what GCC did with LLVM's use of is_stmt many years ago - that was fun, breaking on a function would cause GCC to break on both the function you asked about, and the end of the previous function in the code... due to a bug like this one - it started at the instruction where the function started, then went searching to figure out which statement covered that instruction - which was back in the function that preceeded the one you were trying to break on... good times)

https://github.com/llvm/llvm-project/pull/82240