Collected data "<unavailable>" in trace

[Phi Debian]

Can't reproduce on
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 24.04.1 LTS
Release: 24.04
Codename: noble

$ gcc --version
gcc (Ubuntu 14.2.0-4ubuntu2~24.04) 14.2.0
Copyright (C) 2024 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
============================================================

^C
Program received signal SIGINT, Interrupt.
0x00007ffff7d1ba61 in __GI___libc_read (fd=0, buf=0x5555555596b0,
    nbytes=1024) at ../sysdeps/unix/sysv/linux/read.c:26
warning: 26 ../sysdeps/unix/sysv/linux/read.c: No such file or directory
(gdb) tstop
(gdb) tfind 0
Found trace frame 0, tracepoint 3
#0  main () at m.c:17
17        sum_of_squares += square;
(gdb) tdump
Data collected at tracepoint 3, trace frame 0:
square = 1
cube = 1
(gdb)