https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105240
Bug ID: 105240
Summary: backtrace_pcinfo leaks memory
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libbacktrace
Assignee: unassigned at gcc dot gnu.org
Reporter: redi at gcc dot gnu.org
CC: ian at gcc dot gnu.org
Target Milestone: ---
I'm seeing lots of leaked memory for simple uses of libbacktrace:
$ valgrind --leak-check=full ./stacktrace
==297621== Memcheck, a memory error detector
==297621== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==297621== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==297621== Command: ./stacktrace
==297621==
==297621==
==297621== HEAP SUMMARY:
==297621== in use at exit: 699,881 bytes in 1,134 blocks
==297621== total heap usage: 2,469 allocs, 1,335 frees, 1,473,361 bytes
allocated
==297621==
==297621== 2,286 bytes in 53 blocks are definitely lost in loss record 12 of 20
==297621== at 0x484086F: malloc (vg_replace_malloc.c:381)
==297621== by 0x4113F5: __glibcxx_backtrace_alloc (alloc.c:57)
==297621== by 0x413672: read_lnct (dwarf.c:2543)
==297621== by 0x413672: read_line_header_format_entries (dwarf.c:2618)
==297621== by 0x415286: read_line_header (dwarf.c:2712)
==297621== by 0x415286: read_line_info (dwarf.c:2965)
==297621== by 0x415286: dwarf_lookup_pc (dwarf.c:3747)
==297621== by 0x4162B0: dwarf_fileline (dwarf.c:3935)
==297621== by 0x405B95:
std::stacktrace_entry::_M_get_info(std::__cxx11::basic_string<char,
std::char_traits<char>, std::allocator<char> >*,
std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>
>*, int*) const (stacktrace:186)
==297621== by 0x405885: std::stacktrace_entry::source_line() const
(stacktrace:129)
==297621== by 0x404B08: test_assign() (stacktrace.cc:132)
==297621== by 0x40554E: main (stacktrace.cc:212)
==297621==
==297621== 46,055 bytes in 1 blocks are possibly lost in loss record 17 of 20
==297621== at 0x484086F: malloc (vg_replace_malloc.c:381)
==297621== by 0x4113F5: __glibcxx_backtrace_alloc (alloc.c:57)
==297621== by 0x4112EA: __glibcxx_backtrace_get_view (read.c:68)
==297621== by 0x410CC3: elf_add.constprop.0 (elf.c:4381)
==297621== by 0x4111E3: __glibcxx_backtrace_initialize (elf.c:4877)
==297621== by 0x40BC47: fileline_initialize (fileline.c:261)
==297621== by 0x40BCE5: __glibcxx_backtrace_pcinfo (fileline.c:295)
==297621== by 0x405B95:
std::stacktrace_entry::_M_get_info(std::__cxx11::basic_string<char,
std::char_traits<char>, std::allocator<char> >*,
std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>
>*, int*) const (stacktrace:186)
==297621== by 0x405885: std::stacktrace_entry::source_line() const
(stacktrace:129)
==297621== by 0x404B08: test_assign() (stacktrace.cc:132)
==297621== by 0x40554E: main (stacktrace.cc:212)
==297621==
==297621== LEAK SUMMARY:
==297621== definitely lost: 2,286 bytes in 53 blocks
==297621== indirectly lost: 0 bytes in 0 blocks
==297621== possibly lost: 46,055 bytes in 1 blocks
==297621== still reachable: 651,540 bytes in 1,080 blocks
==297621== suppressed: 0 bytes in 0 blocks
==297621== Reachable blocks (those to which a pointer was found) are not shown.
==297621== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==297621==
==297621== For lists of detected and suppressed errors, rerun with: -s
==297621== ERROR SUMMARY: 2 errors from 2 contexts (suppressed: 0 from 0)
This only happens when libbacktrace uses malloc instead of mmap.
