Please see this bug report in the Perl 5 core distribution.
https://rt.perl.org/Ticket/Display.html?id=123464
When perl is configured with -Dgccansipedantic, Encode fails to compile, thereby causing Perl's 'make' to fail as well. A 'git bisect' reports that these failures began when Encode v2.65 was introduced to core.
See for example the byte_t.c failures grepped in this file:
https://rt.perl.org/Ticket/Attachment/1324369/706116/gccansipedantic_Encode_byte_t_c_errors.txt
Thank you very much.
Jim Keenan