Here's an SSCCE that triggers the issue when profiled by NYTProf:

#!/usr/bin/perl

use strict;
use warnings;
use ExtUtils::Installed;

ExtUtils::Installed->new;
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Output from nytprofhtml with the added warn:

 100% ... WARN:(eval 570)[(eval 569)[/ExtUtils/MM_Unix.pm:2920]:1] at 
+/Devel/NYTProf/FileInfo.pm line 432.
WARN:(eval 570)[(eval 569)[/ExtUtils/MM_Unix.pm:2920]:1] at /Devel/NYT
+Prof/FileInfo.pm line 432.
WARN: at /Devel/NYTProf/FileInfo.pm line 432.
Use of uninitialized value in numeric gt (>) at /Devel/NYTProf/Reader.
+pm line 184.
Use of uninitialized value in numeric gt (>) at /Devel/NYTProf/Reader.
+pm line 185.
Use of uninitialized value $fname in substitution (s///) at /Devel/NYT
+Prof/Util.pm line 235.
Use of uninitialized value $fname in substitution (s///) at /Devel/NYT
+Prof/Util.pm line 237.
Use of uninitialized value $fname in substitution (s///) at /Devel/NYT
+Prof/Util.pm line 238.
Use of uninitialized value in concatenation (.) or string at /Devel/NY
+TProf/Reader.pm line 188.
Use of uninitialized value $_ in substitution (s///) at /bin/nytprofht
+ml line 540.
Use of uninitialized value $_ in substitution (s///) at /bin/nytprofht
+ml line 541.
Use of uninitialized value $_ in substitution (s///) at /bin/nytprofht
+ml line 542.
Use of uninitialized value $_ in substitution (s///) at /bin/nytprofht
+ml line 543.
Use of uninitialized value $_ in substitution (s///) at /bin/nytprofht
+ml line 544.
Use of uninitialized value $_ in substitution (s///) at /bin/nytprofht
+ml line 545.
Use of uninitialized value in sprintf at /bin/nytprofhtml line 202.

Extracting subroutine call data ...
Extracting subroutine links
Generating subroutine stack flame graph ...
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