# native_stack_traces 0.5.4 Utilities for working with non-symbolic stack traces. ## Installing ``` export PUB_HOSTED_URL=https://pub.mirror.p-hatan.ir flutter pub add 'native_stack_traces:0.5.4' ``` Published: 2022-12-21T12:55:55.093321Z Expected archive SHA-256: 56eb633e05db7238653abfef856390256225eba329b9268908795a9b520af899 Available in cache; verification: upstream_checksum ## Direct dependencies - args: ^2.0.0 - path: ^1.8.0 ## Package README (untrusted upstream documentation) [![pub package](https://img.shields.io/pub/v/native_stack_traces.svg)](https://pub.dev/packages/native_stack_traces) [![package publisher](https://img.shields.io/pub/publisher/native_stack_traces.svg)](https://pub.dev/packages/native_stack_traces/publisher) This package provides libraries and a utility for decoding non-symbolic stack traces generated by an AOT-compiled Dart application. ## Converting stack traces In some modes of AOT compilation, information on mapping execution points to source locations is no longer stored in the Dart image. Instead, this information is translated to separately stored debugging information. This debugging information can then be stripped from the application before shipping. However, there is a drawback. Stack traces generated by such an application no longer includes file, function, and line number information (i.e., symbolic stack traces). Instead, stack trace frames simply include program counter information. Thus, to find the source information for these frames, we must use the debugging information. This means either keeping the original unstripped application, or saving the debugging information into a separate file. Given this debugging information, the libraries in this package can turn non-symbolic stack traces back into symbolic stack traces. In addition, this package includes a command line tool `decode` whose output is the same as its input except that non-symbolic stack traces are translated. ### Using `decode` Take the following Dart code, which we put in `throws.dart`. The inlining pragmas are here just to ensure that `bar` is inlined into `foo` and that `foo` is _not_ inlined into `bar`, to illustrate how inlined code is handled in the translated output. ```dart @pragma('vm:prefer-inline') bar() => throw Null; @pragma('vm:never-inline') foo() => bar(); main() => foo(); ``` Now we run the following commands: ```bash # Make sure that we have the native_stack_traces package. $ dart pub global activate native_stack_traces # We compile the example program, removing the source location information # from the snapshot and saving the debugging information into throws.debug. $ dart compile exe -S throws.debug throws.dart # Run the program, saving the error output to throws.err. $ ./throws.exe 2>throws.err # Using the saved debugging information, we can translate the stack trace # contained in throws.err to its symbolic form. $ dart pub global run native_stack_traces:decode translate -d throws.debug -i throws.err ``` ## Features and bugs Please file feature requests and bugs at the [issue tracker][tracker]. [tracker]: https://github.com/dart-lang/sdk/issues ## Changelog ## 0.5.4 - Relaxed requirement for spaces before non-symbolic stack trace line. ## 0.5.3 - Exported more ELF utilities for use in Dart tests. ## 0.5.2 - Adjusted logic for finding the DWARF MachO file in a dSYM. - Added support for retrieving DWARF information from universal macOS binaries using the new architecture information. - Added logic to handle unknown DW_AT, DW_FORM, and DW_TAG codes. ## 0.5.1 - Parse new OS and architecture information from non-symbolic stack trace headers and store that information in PCOffsets when available. ## 0.5.0 - Require Dart >= 2.17 (enhanced enum support) - Add support for parsing DWARF in Mach-O files and dSYM directories. - Add some support for DWARF5. - Add `dump` command to replace the old `--dump_debug_file_contents` flag to `find` and `translate`. ## 0.4.6 - Upgrade to `package:lints` 2.0. - Populate the pubspec `repository` field. ## 0.4.5 - Handle stack traces larger than 100 entries. ## 0.4.5-dev - Require Dart >= 2.14 ## 0.4.4 - Added handling of dynamic tables for testing. ## 0.4.3 - Exported some more of the ELF utilities for use in Dart tests. ## 0.4.2 - When decoding a stack trace, frames corresponding to the functions with DW_AT_artificial DWARF attribute are now omitted from the symbolized stack traces. This is needed because Dart VM no longer omits invisible functions from binary stack traces in certain cases. ## 0.4.1 - Exported some ELF utilities in lib/elf.dart for use in Dart tests. ## 0.4.0 - Stable null safe version of package. ## 0.4.0-nullsafety - Unstable null safe version of package. ## 0.3.8 - Support columns when present in line number programs. ## 0.3.7 - Added buildId accessor for retrieving GNU build IDs from DWARF files that include them. ## 0.3.6 - Adjusts RegExp for stack trace header line to be more flexible in what it permits to allow additional information to be added in the Dart VM. ## 0.3.5 - Use virtual addresses in non-symbolic stack frames as a fallback if we cannot retrieve an appropriate offset from the instructions section otherwise. ## 0.3.4 - Decoded Dart calls are now never considered internal, only VM stub calls. This is due to a concurrent change in the Dart VM that no longer prints non-symbolic frames for functions considered invisible, which matches the symbolic frame printer and removes the need for the decoder to guess which frames should be hidden. This package still works on earlier versions of Dart, so the dependencies have not changed. However, it may print more frame information than expected when decoding stack frames from a Dart VM that does not include this change to non-symbolic stack printing. ## 0.3.3 - No externally visible changes. ## 0.3.2 - The `find` command can now look up addresses given as offsets from static symbols, not just hexadecimal virtual or absolute addresses. - Integer inputs (addresses or offsets) without an '0x' prefix or hexadecimal digits will now be parsed as decimal unless the `-x`/`--force_hexadecimal` flag is used. ## 0.3.1 - Uses dynamic symbol information embedded in stack frame lines when available. ## 0.3.0 - Adds handling of virtual addresses within stub code payloads. ## 0.2.2 - Finds instruction sections by the dynamic symbols the Dart VM creates instead of assuming there are two text sections. ## 0.2.1 - Added static method `Dwarf.fromBuffer`. ## 0.2.0 - API and documentation cleanups ## 0.1.0 - Initial release