loadlibrary throws warnings in 2019b but not in 2017b when loading same DLL

I'm getting a warning when I load my DLL file using 2019b:

Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.30), passed through in regex; marked by <-- HERE in m/struct([^;,{(]){ <-- HERE (.?)}([^;])*;/ at C:\Program Files\MATLAB\R2019b\toolbox\matlab\general\private\prototypes.pl line 912.

When I load the exact same DLL using 2017b, no warning

The library loads in 2019b but when I try to use the library using the calllib function, Matlab dies (get a pop-up that say Matlab encountered an error and had to close). When I do the same call in 2017b, my DLL runs just fine.

I'm wondering if the two are related? Does anyone know or have a fix for this?