Re: [Libunwind-devel] [PATCH] src/dwarf/Gexpr.c (dwarf_eval_expr): Fix the order of the operands to the relational operators to match the DWARF spec.

[Arun Sharma]

On Thu, Jan 31, 2013 at 3:46 AM, Chris January <address@hidden> wrote:

Hello,

I noticed the operands to the relational operators (DW_OP_le, etc.) in
dwarf_eval_expr are reversed compared with the DWARF spec.

Thanks for noticing this. I've applied the patch.

Also curious what real world breakages this patch fixes. The only case using a relational operator I noticed in gcc generated code was in .plt.

$ readelf  -wf /usr/bin/somebinaryl | egrep "OP_gt|le|lt|ge"

  DW_CFA_def_cfa_expression (DW_OP_breg7 (rsp): 8; DW_OP_breg16 (rip): 0; DW_OP_lit15; DW_OP_and; DW_OP_lit11; DW_OP_ge; DW_OP_lit3; DW_OP_shl; DW_OP_plus)

 -Arun