Re: [RFA] Fix size check in dwarf2_evaluate_loc_desc_full

[Simon Marchi <simon.marchi@polymtl.ca>]

On 2017-05-29 18:25, Tom Tromey wrote:
> This Rust bug report:
> 
> https://github.com/rust-lang/rust/issues/41970
> 
> noted an error from gdb.  What is happening here (for me, the original
> report had a different error) is that a pieced DWARF expression is not
> writing to every byte in the resulting value.  GDB errors in this
> case.  However, it seems to me that it is always valid to write fewer
> bytes; the issue comes from writing too many -- that is, the test is
> reversed.  The test was also checking the sub-object, but this also
> seems incorrect, as it's expected for the expression to write the
> entirety of the enclosing object.  So, this patch reverses the test
> and applies it to the outer type, not the subobject type.

Your explanation sounds sensible to me (and the tests suggests it's 
good).  Andreas, since you played with DWARF pieces quite a bit, do you 
have an opinion on this?

Would it be possible to test the error case as well by feeding bad DWARF 
info in the test case?

Thanks!

Simon