gdb show local file frames in thread list - c++

Question

I'm debugging C++ deadlocks with gdb. Inevitably all the deadlock frames are deep inside library functions. For example, __lll_lock_wait is found several layers under mutex::lock(). It would be really great if I could just glance at the thread list to deduce where the deadlock is happening instead of going through the backtrace for each thread.
Example
main.cpp
In this example I purposely introduce deadlock by trying to lock the same mutex twice.
#include <mutex>
#include <thread>
void lock_a(){
std::mutex a;
a.lock();
// attempt to lock something that's already locked
a.lock();
}
int main(){
std::thread t_a(lock_a);
t_a.join();
return 0;
}
compilation & running
clang++ -g main.cpp -lpthread -o main.exe
gdb -ex run --args ./main.exe
gdb
Here I'm trying to figure out what caused the deadlock. If info threads could somehow prioritize "local" files I might find the cause much faster. At long last I'm able to see that I'm trying to lock a mutex in main.cpp
(gdb) info threads
Id Target Id Frame
* 1 Thread 0x7ffff7a41740 (LWP 2651239) "main.exe" __pthread_clockjoin_ex (threadid=140737348110080, thread_return=0x0,
clockid=<optimized out>, abstime=<optimized out>, block=<optimized out>) at pthread_join_common.c:145
2 Thread 0x7ffff7a40700 (LWP 2651293) "main.exe" __lll_lock_wait (futex=futex#entry=0x7ffff7a3fe08, private=0) at lowlevellock.c:52
(gdb) t 2
[Switching to thread 2 (Thread 0x7ffff7a40700 (LWP 2651293))]
#0 __lll_lock_wait (futex=futex#entry=0x7ffff7a3fe08, private=0) at lowlevellock.c:52
52 lowlevellock.c: No such file or directory.
(gdb) f 4
#4 0x0000000000401223 in lock_a () at main.cpp:8
8 a.lock();
Is there some way to have gdb prioritize certain files when listing threads?