docs/CommandGuide/llvm-dwarfdump.md - llvm-project/llvm - Git at Google

 # llvm-dwarfdump - dump and verify DWARF debug information

 ```{program} llvm-dwarfdump
 ```

 ## SYNOPSIS

 {program}`llvm-dwarfdump` \[*options*\] \[*filename ...*\]

 ## DESCRIPTION

 {program}`llvm-dwarfdump` parses DWARF sections in object files,
 archives, and `.dSYM` bundles and prints their contents in
 human-readable form. Only the .debug_info section is printed unless one of
 the section-specific options or {option}`--all` is specified.

 If no input file is specified, `a.out` is used instead. If `-` is used as the
 input file, {program}`llvm-dwarfdump` reads the input from its standard input
 stream.

 ## OPTIONS

 :::{option} -a, --all
 Dump all supported DWARF sections.
 :::

 :::{option} --arch=<arch>
 Dump DWARF debug information for the specified CPU architecture.
 Architectures may be specified by name or by number. This
 option can be specified multiple times, once for each desired
 architecture. All CPU architectures will be printed by
 default.
 :::

 :::{option} -c, --show-children
 Show a debug info entry's children when selectively printing with
 the `=<offset>` argument of {option}`--debug-info`, or options such
 as {option}`--find` or {option}`--name`.
 :::

 :::{option} --color
 Use colors in output.
 :::

 :::{option} --error-display=<value>
 Set the level of detail and summary to display when verifying.
 Implies {option}`--verify`. The supported values are:

 `quiet` - Only display whether errors occurred.
 `summary` - Display only a summary of the errors found.
 `details` - Display each error in detail but no summary.
 `full` - Display each error as well as a summary. [default]
 :::

 :::{option} -f <name>, --find=<name>
 Search for the exact text \<name> in the accelerator tables
 and print the matching debug information entries.
 When there is no accelerator tables or the name of the DIE
 you are looking for is not found in the accelerator tables,
 try using the slower but more complete {option}`--name` option.
 :::

 :::{option} -F, --show-form
 Show DWARF form types after the DWARF attribute types.
 :::

 :::{option} -h, --help
 Show help and usage for this command.
 :::

 :::{option} --help-list
 Show help and usage for this command without grouping the options
 into categories.
 :::

 :::{option} -i, --ignore-case
 Ignore case distinctions when using {option}`--name`.
 :::

 :::{option} -n <name>, --name=<name>
 Find and print all debug info entries whose name
 (`DW_AT_name`/`DW_AT_linkage_name` attribute) is \<name>.
 :::

 :::{option} --lookup=<address>
 Look up \<address> in the debug information and print out the file,
 function, block, and line table details.
 :::

 :::{option} -o <path>
 Redirect output to a file specified by \<path>, where `-` is the
 standard output stream.
 :::

 :::{option} -p, --show-parents
 Show a debug info entry's parents when selectively printing with
 the `=<offset>` argument of {option}`--debug-info`, or options such
 as {option}`--find` or {option}`--name`.
 :::

 :::{option} --parent-recurse-depth=<N>
 When displaying debug info entry parents, only show them to a
 maximum depth of \<N>.
 :::

 :::{option} --quiet
 Use with {option}`--verify` to not emit to `STDOUT`.
 :::

 :::{option} -r <N>, --recurse-depth=<N>
 When displaying debug info entries, only show children to a maximum
 depth of \<N>.
 :::

 :::{option} --show-section-sizes
 Show the sizes of all debug sections, expressed in bytes.
 :::

 :::{option} --show-sources
 Print all source files mentioned in the debug information. Absolute
 paths are given whenever possible.
 :::

 :::{option} --statistics
 Collect debug info quality metrics and print the results
 as machine-readable single-line JSON output. The output
 format is described in the section below ({ref}`stats-format`).
 :::

 :::{option} --summarize-types
 Abbreviate the description of type unit entries.
 :::

 :::{option} -t, --filter-child-tag
 Only dump children whose DWARF tag is one of the specified tags.
 Example usage:

 ```c
 llvm-dwarfdump -t DW_TAG_structure_type -t DW_TAG_member -c
 ```
 :::

 :::{option} -x, --regex
 Treat any \<name> strings as regular expressions when searching
 with {option}`--name`. If {option}`--ignore-case` is also specified,
 the regular expression becomes case-insensitive.
 :::

 :::{option} -u, --uuid
 Show the UUID for each architecture.
 :::

 :::{option} --diff
 Dump the output in a format that is more friendly for comparing
 DWARF output from two different files.
 :::

 :::{option} -v, --verbose
 Display verbose information when dumping. This can help to debug
 DWARF issues.
 :::

 :::{option} --verify
 Verify the structure of the DWARF information by verifying the
 compile unit chains, DIE relationships graph, address
 ranges, and more.
 :::

 :::{option} --verify-json=<path>
 Output JSON-formatted error summary to the file specified by
 \<path>. Implies {option}`--verify`. The output format is described
 in the section below ({ref}`verify-json-format`).
 :::

 :::{option} --version
 Display the version of the tool.
 :::

 :::{option} --debug-abbrev, --debug-addr, --debug-aranges, --debug-cu-index, --debug-frame [=<offset>], --debug-gnu-pubnames, --debug-gnu-pubtypes, --debug-info [=<offset>], --debug-line [=<offset>], --debug-line-str, --debug-loc [=<offset>], --debug-loclists [=<offset>], --debug-macro, --debug-names, --debug-pubnames, --debug-pubtypes, --debug-ranges, --debug-rnglists, --debug-str, --debug-str-offsets, --debug-tu-index, --debug-types [=<offset>], --eh-frame [=<offset>], --gdb-index, --apple-names, --apple-types, --apple-namespaces, --apple-objc
 Dump the specified DWARF section by name. Only the
 `.debug_info` section is shown by default. Some entries
 support adding an `=<offset>` as a way to provide an
 optional offset of the exact entry to dump within the
 respective section. When an offset is provided, only the
 entry at that offset will be dumped, else the entire
 section will be dumped.

 The {option}`--debug-macro` option prints both the .debug_macro and the .debug_macinfo sections.

 The {option}`--debug-frame` and {option}`--eh-frame` options are aliases, in cases where both sections are present one command outputs both.
 :::

 :::{option} --show-variable-coverage
 Show per-variable coverage metrics. The output format is described
 in the section below ({ref}`variable-coverage-format`).
 :::

 :::{option} --coverage-baseline
 File to use as the baseline for variable coverage statistics
 (implies {option}`--show-variable-coverage`)
 :::

 :::{option} --variable-coverage-bitcode-file
 File containing LLVM IR (bitcode or textual) used for calculating
 variable definedness in coverage statistics (implies
 {option}`--show-variable-coverage`)
 :::

 :::{option} --combine-inline-variable-instances
 Use with {option}`--show-variable-coverage` to average variable
 coverage across inlined subroutine instances instead of printing
 them separately.
 :::

 :::{option} @<FILE>
 Read command-line options from `<FILE>`.
 :::

 (stats-format)=

 ## FORMAT OF STATISTICS OUTPUT

 The {option}`--statistics` option generates single-line JSON output
 representing quality metrics of the processed debug info. These metrics are
 useful to compare changes between two compilers, particularly for judging
 the effect that a change to the compiler has on the debug info quality.

 The output is formatted as key-value pairs. The first pair contains a version
 number. The following naming scheme is used for the keys:

 - `variables` ==> local variables and parameters
 - `local vars` ==> local variables
 - `params` ==> formal parameters

 For aggregated values, the following keys are used:

 - `sum_of_all_variables(...)` ==> the sum applied to all variables
 - `#bytes` ==> the number of bytes
 - `#variables - entry values ...` ==> the number of variables excluding
   the entry values etc.

 (verify-json-format)=

 ## FORMAT OF VERIFY JSON OUTPUT

 The format of the JSON output created by the {option}`--verify-json` is:

 ```
 {
   "error-categories": {
     "<first category description>": {"count": 1234},
     "<next category description>": {"count": 4321}
   },
   "error-count": 5555
 }
 ```

 The following is generated if there are no errors reported:

 ```
 {
   "error-categories": {},
   "error-count": 0
 }
 ```

 (variable-coverage-format)=

 ## FORMAT OF VARIABLE COVERAGE OUTPUT

 The {option}`--show-variable-coverage` option differs from
 {option}`--statistics` by printing per-variable debug info coverage metrics
 based on the number of source lines covered instead of the number of
 instruction bytes. Compared to counting instruction bytes, this is more stable
 across compilations and better reflects the debugging experience. The output is
 a tab-separated table containing the following columns:

 - `Function` ==> Name of the function the variable was found in
 - `InstanceCount` (when {option}`--combine-inline-variable-instances` is
   specified) ==> Number of instances of the function; this is 1 for
   functions that have not been inlined, and n+1 for functions that have
   been inlined n times
 - `InlChain` (when {option}`--combine-inline-variable-instances` is not
   specified) ==> Chain of call sites (file and line number) that the
   function has been inlined into; this will be empty if the function has
   not been inlined
 - `Variable` ==> Name of the variable
 - `Decl` ==> Source location (file and line number) of the variable's
   declaration
 - `LinesCovered` ==> Number of source lines covered by the variable's
   debug information in the input file
 - `Baseline` (empty if {option}`--coverage-baseline` is not specified)
   ==> Number of source lines covered by the variable's debug information
   in the baseline
 - `CoveredRatio` (empty if {option}`--coverage-baseline` is not
   specified) ==> Ratio of the coverage compared to the baseline
   (calculated as `LinesCovered/Baseline`)
 - `LinesPresent` (empty if {option}`--coverage-baseline` is not
   specified) ==> Number of source lines covered in the variable's
   baseline debug information that are also present in the input file's
   line table
 - `LinesPresentRatio` (empty if {option}`--coverage-baseline` is not
   specified) ==> Ratio of the line table coverage compared to the
   baseline (calculated as `LinesPresent/Baseline`)

 ## EXIT STATUS

 {program}`llvm-dwarfdump` returns 0 if the input files were parsed and dumped
 successfully. Otherwise, it returns 1.

 ## SEE ALSO

 {manpage}`dsymutil(1)`
	# llvm-dwarfdump - dump and verify DWARF debug information

	```{program} llvm-dwarfdump
	```

	## SYNOPSIS

	{program}`llvm-dwarfdump` \[options\] \[filename ...\]

	## DESCRIPTION

	{program}`llvm-dwarfdump` parses DWARF sections in object files,
	archives, and `.dSYM` bundles and prints their contents in
	human-readable form. Only the .debug_info section is printed unless one of
	the section-specific options or {option}`--all` is specified.

	If no input file is specified, `a.out` is used instead. If `-` is used as the
	input file, {program}`llvm-dwarfdump` reads the input from its standard input
	stream.

	## OPTIONS

	:::{option} -a, --all
	Dump all supported DWARF sections.
	:::

	:::{option} --arch=<arch>
	Dump DWARF debug information for the specified CPU architecture.
	Architectures may be specified by name or by number. This
	option can be specified multiple times, once for each desired
	architecture. All CPU architectures will be printed by
	default.
	:::

	:::{option} -c, --show-children
	Show a debug info entry's children when selectively printing with
	the `=<offset>` argument of {option}`--debug-info`, or options such
	as {option}`--find` or {option}`--name`.
	:::

	:::{option} --color
	Use colors in output.
	:::

	:::{option} --error-display=<value>
	Set the level of detail and summary to display when verifying.
	Implies {option}`--verify`. The supported values are:

	`quiet` - Only display whether errors occurred.
	`summary` - Display only a summary of the errors found.
	`details` - Display each error in detail but no summary.
	`full` - Display each error as well as a summary. [default]
	:::

	:::{option} -f <name>, --find=<name>
	Search for the exact text \<name> in the accelerator tables
	and print the matching debug information entries.
	When there is no accelerator tables or the name of the DIE
	you are looking for is not found in the accelerator tables,
	try using the slower but more complete {option}`--name` option.
	:::

	:::{option} -F, --show-form
	Show DWARF form types after the DWARF attribute types.
	:::

	:::{option} -h, --help
	Show help and usage for this command.
	:::

	:::{option} --help-list
	Show help and usage for this command without grouping the options
	into categories.
	:::

	:::{option} -i, --ignore-case
	Ignore case distinctions when using {option}`--name`.
	:::

	:::{option} -n <name>, --name=<name>
	Find and print all debug info entries whose name
	(`DW_AT_name`/`DW_AT_linkage_name` attribute) is \<name>.
	:::

	:::{option} --lookup=<address>
	Look up \<address> in the debug information and print out the file,
	function, block, and line table details.
	:::

	:::{option} -o <path>
	Redirect output to a file specified by \<path>, where `-` is the
	standard output stream.
	:::

	:::{option} -p, --show-parents
	Show a debug info entry's parents when selectively printing with
	the `=<offset>` argument of {option}`--debug-info`, or options such
	as {option}`--find` or {option}`--name`.
	:::

	:::{option} --parent-recurse-depth=<N>
	When displaying debug info entry parents, only show them to a
	maximum depth of \<N>.
	:::

	:::{option} --quiet
	Use with {option}`--verify` to not emit to `STDOUT`.
	:::

	:::{option} -r <N>, --recurse-depth=<N>
	When displaying debug info entries, only show children to a maximum
	depth of \<N>.
	:::

	:::{option} --show-section-sizes
	Show the sizes of all debug sections, expressed in bytes.
	:::

	:::{option} --show-sources
	Print all source files mentioned in the debug information. Absolute
	paths are given whenever possible.
	:::

	:::{option} --statistics
	Collect debug info quality metrics and print the results
	as machine-readable single-line JSON output. The output
	format is described in the section below ({ref}`stats-format`).
	:::

	:::{option} --summarize-types
	Abbreviate the description of type unit entries.
	:::

	:::{option} -t, --filter-child-tag
	Only dump children whose DWARF tag is one of the specified tags.
	Example usage:

	```c
	llvm-dwarfdump -t DW_TAG_structure_type -t DW_TAG_member -c
	```
	:::

	:::{option} -x, --regex
	Treat any \<name> strings as regular expressions when searching
	with {option}`--name`. If {option}`--ignore-case` is also specified,
	the regular expression becomes case-insensitive.
	:::

	:::{option} -u, --uuid
	Show the UUID for each architecture.
	:::

	:::{option} --diff
	Dump the output in a format that is more friendly for comparing
	DWARF output from two different files.
	:::

	:::{option} -v, --verbose
	Display verbose information when dumping. This can help to debug
	DWARF issues.
	:::

	:::{option} --verify
	Verify the structure of the DWARF information by verifying the
	compile unit chains, DIE relationships graph, address
	ranges, and more.
	:::

	:::{option} --verify-json=<path>
	Output JSON-formatted error summary to the file specified by
	\<path>. Implies {option}`--verify`. The output format is described
	in the section below ({ref}`verify-json-format`).
	:::

	:::{option} --version
	Display the version of the tool.
	:::

	:::{option} --debug-abbrev, --debug-addr, --debug-aranges, --debug-cu-index, --debug-frame [=<offset>], --debug-gnu-pubnames, --debug-gnu-pubtypes, --debug-info [=<offset>], --debug-line [=<offset>], --debug-line-str, --debug-loc [=<offset>], --debug-loclists [=<offset>], --debug-macro, --debug-names, --debug-pubnames, --debug-pubtypes, --debug-ranges, --debug-rnglists, --debug-str, --debug-str-offsets, --debug-tu-index, --debug-types [=<offset>], --eh-frame [=<offset>], --gdb-index, --apple-names, --apple-types, --apple-namespaces, --apple-objc
	Dump the specified DWARF section by name. Only the
	`.debug_info` section is shown by default. Some entries
	support adding an `=<offset>` as a way to provide an
	optional offset of the exact entry to dump within the
	respective section. When an offset is provided, only the
	entry at that offset will be dumped, else the entire
	section will be dumped.

	The {option}`--debug-macro` option prints both the .debug_macro and the .debug_macinfo sections.

	The {option}`--debug-frame` and {option}`--eh-frame` options are aliases, in cases where both sections are present one command outputs both.
	:::

	:::{option} --show-variable-coverage
	Show per-variable coverage metrics. The output format is described
	in the section below ({ref}`variable-coverage-format`).
	:::

	:::{option} --coverage-baseline
	File to use as the baseline for variable coverage statistics
	(implies {option}`--show-variable-coverage`)
	:::

	:::{option} --variable-coverage-bitcode-file
	File containing LLVM IR (bitcode or textual) used for calculating
	variable definedness in coverage statistics (implies
	{option}`--show-variable-coverage`)
	:::

	:::{option} --combine-inline-variable-instances
	Use with {option}`--show-variable-coverage` to average variable
	coverage across inlined subroutine instances instead of printing
	them separately.
	:::

	:::{option} @<FILE>
	Read command-line options from `<FILE>`.
	:::

	(stats-format)=

	## FORMAT OF STATISTICS OUTPUT

	The {option}`--statistics` option generates single-line JSON output
	representing quality metrics of the processed debug info. These metrics are
	useful to compare changes between two compilers, particularly for judging
	the effect that a change to the compiler has on the debug info quality.

	The output is formatted as key-value pairs. The first pair contains a version
	number. The following naming scheme is used for the keys:

	- `variables` ==> local variables and parameters
	- `local vars` ==> local variables
	- `params` ==> formal parameters

	For aggregated values, the following keys are used:

	- `sum_of_all_variables(...)` ==> the sum applied to all variables
	- `#bytes` ==> the number of bytes
	- `#variables - entry values ...` ==> the number of variables excluding
	the entry values etc.

	(verify-json-format)=

	## FORMAT OF VERIFY JSON OUTPUT

	The format of the JSON output created by the {option}`--verify-json` is:

	```
	{
	"error-categories": {
	"<first category description>": {"count": 1234},
	"<next category description>": {"count": 4321}
	},
	"error-count": 5555
	}
	```

	The following is generated if there are no errors reported:

	```
	{
	"error-categories": {},
	"error-count": 0
	}
	```

	(variable-coverage-format)=

	## FORMAT OF VARIABLE COVERAGE OUTPUT

	The {option}`--show-variable-coverage` option differs from
	{option}`--statistics` by printing per-variable debug info coverage metrics
	based on the number of source lines covered instead of the number of
	instruction bytes. Compared to counting instruction bytes, this is more stable
	across compilations and better reflects the debugging experience. The output is
	a tab-separated table containing the following columns:

	- `Function` ==> Name of the function the variable was found in
	- `InstanceCount` (when {option}`--combine-inline-variable-instances` is
	specified) ==> Number of instances of the function; this is 1 for
	functions that have not been inlined, and n+1 for functions that have
	been inlined n times
	- `InlChain` (when {option}`--combine-inline-variable-instances` is not
	specified) ==> Chain of call sites (file and line number) that the
	function has been inlined into; this will be empty if the function has
	not been inlined
	- `Variable` ==> Name of the variable
	- `Decl` ==> Source location (file and line number) of the variable's
	declaration
	- `LinesCovered` ==> Number of source lines covered by the variable's
	debug information in the input file
	- `Baseline` (empty if {option}`--coverage-baseline` is not specified)
	==> Number of source lines covered by the variable's debug information
	in the baseline
	- `CoveredRatio` (empty if {option}`--coverage-baseline` is not
	specified) ==> Ratio of the coverage compared to the baseline
	(calculated as `LinesCovered/Baseline`)
	- `LinesPresent` (empty if {option}`--coverage-baseline` is not
	specified) ==> Number of source lines covered in the variable's
	baseline debug information that are also present in the input file's
	line table
	- `LinesPresentRatio` (empty if {option}`--coverage-baseline` is not
	specified) ==> Ratio of the line table coverage compared to the
	baseline (calculated as `LinesPresent/Baseline`)

	## EXIT STATUS

	{program}`llvm-dwarfdump` returns 0 if the input files were parsed and dumped
	successfully. Otherwise, it returns 1.

	## SEE ALSO

	{manpage}`dsymutil(1)`