---
name: "dh_dwz"
section: "1"
platform: "linux"
package: "debhelper"
version: "13.24.2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/dh_dwz"
---

# dh\_dwz(1)

optimize DWARF debug information in ELF binaries via dwz

## NAME

dh\_dwz - optimize DWARF debug information in ELF binaries via dwz

## SYNOPSIS

**dh\_dwz** \[*debhelper options*\] \[**-X***item*\] \[**--** *params*\]

## DESCRIPTION

**dh\_dwz** is a debhelper program that will optimize the (uncompressed) size of the DWARF debug information in ELF binaries.  It does so by running [**dwz**(1)](/dwz/1.md) on all the ELF binaries in the package.

## OPTIONS

- **--dwz-multifile**, **--no-dwz-multifile**

  Whether [**dwz**(1)](/dwz/1.md) should generate a *multifile* from the ELF binaries in the same package.  When enabled, if a package ships at least 2 ELF binaries, **dh\_dwz** will instruct [**dwz**(1)](/dwz/1.md) to generate a multifile for the package.

  By default, **dh\_dwz** will attempt to create a multifile but will continue without if [**dwz**(1)](/dwz/1.md) does not create one (but succeeds anyway). This commonly happens when the debug files do not contain debug symbols (e.g. a missing -g to the compiler) or when the debug symbols are compressed (see Debian bug #931891).  If **--dwz-multifile** is passed, then **dh\_dwz** will abort with an error if [**dwz**(1)](/dwz/1.md) does not create a multifile.

  Note this options may not work if a package contains more ELF binaries than can fit on a single command line.  If this becomes a problem, please pass **--no-dwz-multifile** to work around the issue.

  The generated multifile will be compressed with **objcopy** **--compress-debug-sections**.

  Note for **udeb** packages: **dh\_dwz** will never generate multifiles for **udeb** packages.  It will still use **dwz** to reduce the file size of debug files if it finds any.

- **-X***item*, **--exclude=***item*

  Exclude files that contain *item* anywhere in their filename from being stripped. You may use this option multiple times to build up a list of things to exclude.

- **--** *params*

  Pass *params* to [**dwz**(1)](/dwz/1.md) when it processes ELF binaries.  This is mostly useful for setting memory related parameters (e.g. -l and -L).

## NOTES

If the **DEB\_BUILD\_OPTIONS** environment variable contains **nostrip**, nothing will be stripped, in accordance with Debian policy (section 10.1 "Binaries").

While this tool technically does not remove debug information from binaries, it is still skipped when the **DEB\_BUILD\_OPTIONS** environment variable contains **nostrip**.  This is because **nostrip** is often used to optimize build times (e.g. for "build and test"-cycles) rather than optimizing for size.

## SEE ALSO

[**debhelper**(7)](/debhelper/7.md)

This program is a part of debhelper.

## AUTHOR

Niels Thykier \<niels@thykier.net\>