[llvm-commits] [llvm] r169218 - in /llvm/trunk: include/llvm/ lib/CodeGen/AsmPrinter/ lib/VMCore/ test/CodeGen/ARM/ test/CodeGen/Thumb/ test/CodeGen/X86/ test/DebugInfo/ test/DebugInfo/X86/ test/JitListener/

[Duncan Sands]

Hi Eric,

On 05/12/12 00:45, Eric Christopher wrote:
>
>
>      > Omitting DW_AT_lower_bound is a language-dependent operation.  LLVM
>      > currently is not treating it that way; it is assuming the default
>      > lower bound is 0 for all languages.
>      >
>     Ah, I see what you mean. Yeah, this is bad. Eric should be the one to
>     determine if we should always output the lower bound attribute. :)
>
>
> Way to punt. ;)
>
> Anyhow, we'd want to do this for Fortran (default = 1) and (conceivably) Ada
> (default = 1 or -1 depending on dwarf version), if we cared (these are the
> languages supported by DragonEgg). Duncan? I'll also use this to poke Duncan
> about moving to DIBuilder :)

is this about a default, used when the language front-end forgot to provide a
lower bound?  For Ada there isn't really any sensible default, but 1 is better
than 0.  The Ada front-end should just specify explicitly what the lower bound
is for each object/type.  For Fortran 1 makes sense, but again better if the
front-end is explicit about it.  I don't have time to read the rest of the
thread right now, so I'm a bit lost as to what this is all about and why it is
related to DIBuilder.  I've been trying hard not to have to understand how debug
info works, but it sounds like those halcyon days are drawing to a close!

Ciao, Duncan.


>
> -eric
>
> ps. (One more parenthetical).