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@LotharSee LotharSee commented Jun 27, 2016

Instead of letting each integration having their own weird way of try import stuff (which then fallback on a None, object, whatever...), us a common way to test missing dependencies on the __init__ of each contrib.
Do it everywhere.
Exploit it in the tests.

This way, the integration code itself can safely import anything for the libraries.

if not missing_modules:
from .connection import connection_factory

__all__ = ['connection_factory']
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hmm. not sure about this.

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About its usefulness or its usage?
It is just to have a sane "import *" and to prevent linter errors.

@clutchski
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how will this work in production code?

@LotharSee
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In production, there isn't a great difference, except that ddtrace.contrib.whatever won't contain instrumentation methods for whatever if its dependencies aren't met. If the dependency is installed, nothing really changed.
So it is mostly a code cleanup, and a common way to manage that.

@LotharSee LotharSee merged commit 352539b into master Jun 28, 2016
@LotharSee LotharSee deleted the benjamin/restructure-contrib-imports branch June 28, 2016 17:33
labbati added a commit that referenced this pull request Sep 13, 2018
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```
github-actions bot pushed a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 29, 2024
The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)
nsrip-dd added a commit that referenced this pull request Oct 30, 2024
…t 2.12] (#11215)

Backport 64b3374 from #11167 to 2.12.

The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to
wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)
nsrip-dd added a commit that referenced this pull request Oct 30, 2024
…t 2.13] (#11214)

Backport 64b3374 from #11167 to 2.13.

The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to
wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)
nsrip-dd added a commit that referenced this pull request Oct 30, 2024
…t 2.14] (#11213)

Backport 64b3374 from #11167 to 2.14.

The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to
wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)
taegyunkim added a commit that referenced this pull request Oct 30, 2024
…t 2.15] (#11211)

Backport 64b3374 from #11167 to 2.15.

The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member function sets the active span for a thread.
`get_active_span_from_thread_id` accesses the map of spans under a
mutex, but returns the pointer after releasing the mutex, meaning
`link_span` can modify the members of the Span while the caller of
`get_active_span_from_thread_id` is reading them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to
wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

(cherry picked from commit 64b3374)

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

Co-authored-by: Taegyun Kim <taegyun.kim@datadoghq.com>
taegyunkim added a commit that referenced this pull request Oct 30, 2024
…t 2.16] (#11210)

Backport 64b3374 from #11167 to 2.16.

The ThreadSpanLinks singleton holds the active span (if one exists) for
a given thread ID. The `get_active_span_from_thread_id` member function
returns a pointer to the active span for a thread. The `link_span`
member
function sets the active span for a thread.
`get_active_span_from_thread_id`
accesses the map of spans under a mutex, but returns the pointer after
releasing the mutex, meaning `link_span` can modify the members of the
Span while the caller of `get_active_span_from_thread_id` is reading
them.

Fix this by returning a copy of the `Span`. Use a `std::optional` to
wrap
the return value of `get_active_span_from_thread_id`, rather than
returning a pointer. We want to tell whether or not there actually was a
span associated with the thread, but returning a pointer would require
us to heap allocate the copy of the Span.

I added a simplistic regression test which fails reliably without this
fix
when built with the thread sanitizer enabled. Output like:

```
WARNING: ThreadSanitizer: data race (pid=2971510)
  Read of size 8 at 0x7b2000004080 by thread T2:
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::__invoke_impl<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__invoke_other, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe46e)
    #4 std::__invoke_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>::type std::__invoke<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()>(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*&&)()) <null> (thread_span_links+0xe2fe)
    #5 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe1cf)
    #6 std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> >::operator()() <null> (thread_span_links+0xe0f6)
    #7 std::thread::_State_impl<std::thread::_Invoker<std::tuple<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > (*)()> > >::_M_run() <null> (thread_span_links+0xdf40)
    #8 <null> <null> (libstdc++.so.6+0xd6df3)

  Previous write of size 8 at 0x7b2000004080 by thread T1 (mutexes: write M47):
    #0 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:823 (libtsan.so.0+0x42313)
    #1 memcpy ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:815 (libtsan.so.0+0x42313)
    #2 std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_assign(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocato
r<char> > const&) <null> (libstdc++.so.6+0x1432b4)
    #3 get() <null> (thread_span_links+0xb570)
    #4 void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) <null> (thread_span_links+0xe525)
    #5 std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) <null> (thread_span_links+0xe3b5)
    #6 void std::thread::_Invoker<std::tuple<void (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) <null> (thread_span_links+0xe242)
    #7 std::thread::_Invoker<std::tuple<void (*)()> >::operator()() <null> (thread_span_links+0xe158)
[ ... etc ... ]
```

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

Co-authored-by: Nick Ripley <nick.ripley@datadoghq.com>
Co-authored-by: Taegyun Kim <taegyun.kim@datadoghq.com>
taegyunkim added a commit that referenced this pull request Oct 9, 2025
## Description

`test_wrapper()` segfaults with following stack backtrace

```
#3  handle_posix_sigaction () at src/collector/crash_handler.rs:108
#4  <signal handler called>
#5  0x000075fb182a92b9 in Datadog::Sample::push_release (count=1, lock_time=3896666036706324, this=<optimized out>)
    at /home/bits/project/ddtrace/internal/datadog/profiling/dd_wrapper/src/sample.cpp:235
#6  Datadog::Sample::push_release (this=<optimized out>, lock_time=3896666036706324, count=1)
    at /home/bits/project/ddtrace/internal/datadog/profiling/dd_wrapper/src/sample.cpp:231
#7  0x000075fb182bec5c in __pyx_pf_7ddtrace_8internal_7datadog_9profiling_4ddup_5_ddup_12SampleHandle_10push_release (
    __pyx_v_count=<optimized out>, __pyx_v_value=0x75fb187c7250, __pyx_v_self=0x75fb187c7630)
    at /tmp/tmpxso4scef.build-lib/ddtrace.internal.datadog.profiling.ddup._ddup/_ddup.cpp:7956
#8  __pyx_pw_7ddtrace_8internal_7datadog_9profiling_4ddup_5_ddup_12SampleHandle_11push_release (
    __pyx_v_self=0x75fb187c7630, __pyx_args=<optimized out>, __pyx_nargs=<optimized out>, __pyx_kwds=<optimized out>)
    at /tmp/tmpxso4scef.build-lib/ddtrace.internal.datadog.profiling.ddup._ddup/_ddup.cpp:7907
#9  0x000075fb1c35b495 in _PyObject_VectorcallTstate (kwnames=0x0, nargsf=<optimized out>, args=0x59d0af703300,
```

As it indexes into empty `values`
[vector](https://github.com/DataDog/dd-trace-py/blob/d033f37c48994b061a00748a00724b54a110de39/ddtrace/internal/datadog/profiling/dd_wrapper/include/sample.hpp#L81).
It is typically initialized by a call to `ddup.config()`. Shuffle the
test code into `TestThreadingLockCollector` class to do so.

<!-- Provide an overview of the change and motivation for the change -->

## Testing

Run `CMAKE_BUILD_PARALLEL_LEVEL=$(nproc) DD_FAST_BUILD=1
DD_TRACE_AGENT_URL=http://localhost:8126 riot -v run 9bb19fe --pass-env
-- -s -vv -k test_wrapper`

<!-- Describe your testing strategy or note what tests are included -->

## Risks

<!-- Note any risks associated with this change, or "None" if no risks
-->

## Additional Notes

<!-- Any other information that would be helpful for reviewers -->

[PROF-12678](https://datadoghq.atlassian.net/browse/PROF-12678)

[PROF-12678]:
https://datadoghq.atlassian.net/browse/PROF-12678?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ
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3 participants