Ian Lance Taylor
6d913c4521
Based on patch by Andi Kleen. * backtrace.h (struct backtrace_moredata): Add backtrace_decl_lineno field. * internal.h (BACKTRACE_MOREDATA_VERSION): Change to 4. * dwarf.c (struct function): Add decl_lineno field. (call_callback): Add decl_lineno parameter. Change all callers. (read_referenced_name_from_attr): Likewise. (read_referenced_name): Likewise. (report_inlined_functions): Likewise. (read_function_entry): Set decl_lineno field. (dwarf_lookup_pc): Handle decl_lineno across inlines. * mdtest.c (struct mdinfo): Define. (struct mddata): Define. (md_callback_one): Adjust for mddata. (md_callback_three): Likewise. (test1, f2): Reformat for simpler line number testing. (f3): Test that decl_lineno is correct. (f13): Adjust for mddata.
libbacktrace
A C library that may be linked into a C/C++ program to produce symbolic backtraces
Initially written by Ian Lance Taylor iant@golang.org.
This is version 1.0. It is likely that this will always be version 1.0.
The libbacktrace library may be linked into a program or library and used to produce symbolic backtraces. Sample uses would be to print a detailed backtrace when an error occurs or to gather detailed profiling information.
In general the functions provided by this library are async-signal-safe,
meaning that they may be safely called from a signal handler.
That said, on systems that use dl_iterate_phdr, such as GNU/Linux,
the first call to a libbacktrace function will call dl_iterate_phdr,
which is not in general async-signal-safe. Therefore, programs
that call libbacktrace from a signal handler should ensure that they
make an initial call from outside of a signal handler.
Similar considerations apply when arranging to call libbacktrace
from within malloc; dl_iterate_phdr can also call malloc,
so make an initial call to a libbacktrace function outside of
malloc before trying to call libbacktrace functions within malloc.
The libbacktrace library is provided under a BSD license. See the source files for the exact license text.
The public functions are declared and documented in the header file backtrace.h, which should be #include'd by a user of the library.
Building libbacktrace will generate a file backtrace-supported.h, which a user of the library may use to determine whether backtraces will work. See the source file backtrace-supported.h.in for the macros that it defines.
As of July 2024, libbacktrace supports ELF, PE/COFF, Mach-O, and XCOFF executables with DWARF debugging information. In other words, it supports GNU/Linux, *BSD, macOS, Windows, and AIX. The library is written to make it straightforward to add support for other object file and debugging formats.
The library relies on the C++ unwind API defined at https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html This API is provided by GCC and clang.