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Re: [PATCH] Use libbacktrace as libsanitizer's symbolizer

On Wed, Nov 27, 2013 at 4:51 PM, Jakub Jelinek <> wrote:
> On Wed, Nov 27, 2013 at 04:31:48PM +0400, Alexey Samsonov wrote:
>> LLVM emits just a DW_AT_low_pc ("base address" of a compilation unit). The
>> standard tells that compilation unit entries "may have" attributes
>> specifying the
>> address range, but doesn't tell they are obligatory.
>> DWARF consumers probably shouldn't rely on their presence.
> DWARF is generally full of may have and almost no must have.  If the
> DWARF consumer crashes on absence of some attribute/die etc., that would
> be of course a consumer's fault.  But not being able to symbolize something
> because the provided DWARF info omits important stuff is not wrong.

Ok, I agree to call it "missing feature" instead of "bug" =)

> BTW, libbacktrace also uses symbol table (and for backtrace_syminfo
> uses that exclusively), so even if it can't symbolize using DWARF info,
> it should at least symbolize using symbol table (of course inlining info
> isn't available in that case, nor tail call frames (but libbacktrace doesn't
> support those yet, only GDB does so far)).

Yes, symbol table symbolization works for me (it has no file/line
info, of course).

Alexey Samsonov, MSK

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