llvm-dwarfutil - A tool to copy and manipulate debug info

SYNOPSIS

llvm-dwarfutil [options] input output

DESCRIPTION

llvm-dwarfutil is a tool to copy and manipulate debug info.

In basic usage, it makes a semantic copy of the input to the output. If any options are specified, the output may be modified along the way, e.g. by removing unused debug info.

If “-” is specified for the input file, the input is read from the program’s standard input stream. If “-” is specified for the output file, the output is written to the standard output stream of the program.

The tool is still in active development.

COMMAND-LINE OPTIONS

:::{option} –garbage-collection Removes pieces of debug information related to discarded sections. When the linker does section garbage collection the abandoned debug info is left behind. Such abandoned debug info references address ranges using tombstone values. Thus, when this option is specified, the tool removes debug info which is marked with the tombstone value.

That option is enabled by default. :::

:::{option} –odr-deduplication Remove duplicated types (if “One Definition Rule” is supported by source language). Keeps first type definition and removes other definitions, potentially significantly reducing the size of output debug info.

That option is enabled by default. :::

:::{option} –compress-debug-sections= Compress the debug sections of the output using the specified format. <format> can be one of the following values:

  • none: do not compress debug sections.

  • zlib: compress debug sections using zlib.

  • zstd: compress debug sections using zstd.

zlib is used if =<format> is omitted. By default, the output debug sections are compressed only if the input debug sections are compressed, using the same format. :::

:::{option} –help, -h Print a summary of command line options. :::

:::{option} –no-compress-debug-sections Disable --compress-debug-sections. Equivalent to --compress-debug-sections=none. :::

:::{option} –no-garbage-collection Disable --garbage-collection. :::

:::{option} –no-odr-deduplication Disable --odr-deduplication. :::

:::{option} –no-separate-debug-file Disable --separate-debug-file. :::

:::{option} –num-threads=, -j Specifies the maximum number (n) of simultaneous threads to use for processing. :::

:::{option} –separate-debug-file Generate separate file containing output debug info. Using llvm-dwarfutil with that option equals to the following set of commands: :::

:program:`llvm-objcopy` --only-keep-debug in-file out-file.debug
:program:`llvm-objcopy` --strip-debug in-file out-file
:program:`llvm-objcopy` --add-gnu-debuglink=out-file.debug out-file

:::{option} –tombstone= <value> can be one of the following values:

  • bfd: zero for all addresses and [1,1] for DWARF v4 (or less) address ranges and exec.

  • maxpc: -1 for all addresses and -2 for DWARF v4 (or less) address ranges.

  • universal: both bfd and maxpc.

  • exec: match with address ranges of executable sections.

The value universal is used by default. :::

:::{option} –verbose Enable verbose logging. This option disables multi-thread mode. :::

:::{option} –verify Run the DWARF verifier on the output DWARF debug info. :::

:::{option} –version Print the version of this program. :::

SUPPORTED FORMATS

The following formats are currently supported by llvm-dwarfutil:

ELF

EXIT STATUS

llvm-dwarfutil exits with a non-zero exit code if there is an error. Otherwise, it exits with code 0.

BUGS

To report bugs, please visit <https://github.com/llvm/llvm-project/labels/tools:llvm-dwarfutil/>.