Bug #17823: addr2line.c: Interpret `DW_RLE_start_length`

• Status: Closed
• Assignee: -
• Target version: -
• Backport: 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN

[xtkoba (Tee KOBAYASHI)]

I noticed some of the symbol names were missing from C backtrace for an i686-linux binary built with GCC 10.3 + DWARF 5, and found that the form DW_RLE_start_length is used in it. This form was left uninterpreted in addr2line.c, because at the time of implementation the main purpose was to suppress segfaults (#17585).

The attached patch implements the interpretation of DW_RLE_start_length and DW_RLE_start_end. It also fixes some minor errors in the function ranges_include, mainly around the base address handling.

The patch also fixes the function read_dw_form_addr to use the correct address size (reader->address_size).

Note that the DW_RLE_*'s that require .debug_addr section are still left uninterpreted.

[xtkoba (Tee KOBAYASHI)]

PR: https://github.com/ruby/ruby/pull/4439

[xtkoba (Tee KOBAYASHI)]

• File ruby-addr2line-interpret-DW_RLE_start_length-r1.patch ruby-addr2line-interpret-DW_RLE_start_length-r1.patch added

An edited patch is attached so that it applies cleanly to the current master head.

[xtkoba (Tee KOBAYASHI)]

• File deleted (ruby-addr2line-interpret-DW_RLE_start_length.patch)

[xtkoba (Tee KOBAYASHI)]

• Status changed from Open to Closed

Applied in changeset git|77e6715d67b92b16bcb4588e0da37b494cdc5278.

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Interpret DW_RLE_start_length

Fixes [Bug #17823]