[llvm-dev] workaround to force LLD to make dwarf info sections mappable/loadable?

[Friedman, Eli via llvm-dev]

On 12/3/2018 12:34 PM, Andrew Kelley via llvm-dev wrote:
> Context: https://bugs.llvm.org/show_bug.cgi?id=39862
>
> I'm trying to enable stack traces in an OS kernel. To do that the kernel
> needs access to its own debug info.

Unwind info is usually emitted into an allocatable section, so you can 
compute a stack trace without looking at debug info. Of course, that 
doesn't include any symbol information, but you can compute the 
corresponding symbols offline.

IIRC the Linux kernel uses a custom format for symbol information; the 
build system post-processes the object files to compute the relevant 
information, and uses objcopy to insert the information into an 
allocatable section.

-Eli

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