I ran into a FPE once.... and while I've not dug into the details, I can give a somewhat dirty way to reproduce it. It is dirty because the bug causing the FPE has been fixed since then. Here's the code:

$SIG{FPE} = sub { die "Ooops\n" };
use List::Util 'product';
print product(-1,1);
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If you run this in vanilla Perl 5.34 or older without a signal handler, it dies with Floating point exception. If you include the handler like I did, you'll get:

If you run this in vanilla Perl 5.36, you get the expected result of -1, because the bug (RT139601) has been fixed in that release (in List::Util 1.60, to be precise). But you can catch the FPE by installing an "older" List::Util on top of Perl 5.36:

cpanm https://cpan.metacpan.org/authors/id/P/PE/PEVANS/Scalar-List-Uti
+ls-1.59.tar.gz
perl fpe.pl
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This dies with the message Ooops, so in Perl 5.36 the signal handler works as you'd expect.

Don't forget to upgrade your List::Util after that test :)

Great, thanks. I'll dig into the older List::Util to see how the error happens, as I don't want to install an older version of a core module in the test suite of Syntax::Construct :-)
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

Here's the case that caused me to investigate and add this change in the first place:

% $PERL-5.34.0 -MMath::GMP -wle 'local $SIG{FPE} = sub { die "fpe" }; 
+$z=Math::GMP->new(1); print $z / 0'
Maximal count of pending signals (120) exceeded at -e line 1.
fpe at -e line 1.
% 
% $PERL-5.36.0 -MMath::GMP -wle 'local $SIG{FPE} = sub { die "fpe" }; 
+$z=Math::GMP->new(1); print $z / 0'
fpe at -e line 1.
%
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The original ticket was Catching SIGFPE. Not sure why my example above isn't reproducing that, but in my real-world code this was stopping me from getting a stack trace to find where the division by zero was occurring.

Despite the name, this exception is primarily raised for integer division by zero, so the Inline::C example needs s{float}{int}g to show it. See why was sigfpe used for integer arithmetic exceptions for some more detail.

Perl itself catches these when it performs a division, so you'll only see it from non-perl code linked to your program.

I can confirm that with ints, it emits "Maximal count of pending signals". It still outputs the line number, as you noted. Probably not worth including into Syntax::Construct, as the change in behaviour is hard to test and the code probably doesn't depend on that (the user debugging the code, though, might well do).
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

This is rather strange - removing the 'local' stops the die message from showing up:

% perl-5.34.0 -MMath::GMP -wle 'local $SIG{FPE} = sub { die "divide by
+ zero" };
  $z=Math::GMP->new(1); print $z / 0'
Maximal count of pending signals (120) exceeded at -e line 1.
divide by zero at -e line 1.
% 
% perl-5.34.0 -MMath::GMP -wle '$SIG{FPE} = sub { die "divide by zero"
+ };
  $z=Math::GMP->new(1); print $z / 0'
Maximal count of pending signals (120) exceeded at -e line 1.
%
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I don't know why that's occurring. I guess it's possible there's a bug here, but I'm not sure how I might start investigating it. If anything I'd have imagined it working the other way round.