Initialize some variables, and use memcpy() instead of strncpy().
Remove the -Wno-error options. This broke on Debian 8 ppc (gcc-4.9.2),
which doesn't support -Wstringop-overflow or -Wstringop-truncation.
extlib/minizip-ng/compat/unzip.c: In function ‘unzGetFilePos’:
extlib/minizip-ng/compat/unzip.c:563:38: error: ‘file_pos64.pos_in_zip_directory’ may be used uninitialized [-Werror=maybe-uninitialized]
563 | file_pos->pos_in_zip_directory = (uint32_t)file_pos64.pos_in_zip_directory;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
extlib/minizip-ng/compat/unzip.c:556:20: note: ‘file_pos64.pos_in_zip_directory’ was declared here
556 | unz64_file_pos file_pos64;
| ^~~~~~~~~~
extlib/minizip-ng/compat/unzip.c:564:29: error: ‘file_pos64.num_of_file’ may be used uninitialized [-Werror=maybe-uninitialized]
564 | file_pos->num_of_file = (uint32_t)file_pos64.num_of_file;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
extlib/minizip-ng/compat/unzip.c:556:20: note: ‘file_pos64.num_of_file’ was declared here
556 | unz64_file_pos file_pos64;
| ^~~~~~~~~~
cc1: all warnings being treated as errors
extlib/minizip-ng/mz_zip.c: In function ‘mz_zip_set_comment’:
extlib/minizip-ng/mz_zip.c:1569:5: error: ‘__builtin___strncpy_chk’ output truncated before terminating nul copying as many bytes from a string as its length [-Werror=stringop-truncation]
1569 | strncpy(zip->comment, comment, comment_size);
| ^
extlib/minizip-ng/mz_zip.c:1563:29: note: length computed here
1563 | comment_size = (int32_t)strlen(comment);
| ^~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Reference: https://fedoraproject.org/wiki/Format-Security-FAQ
-Werror=format-nonliteral is *not* enabled because there are some
legitimate uses of non-literal format strings.
Separated the warning flags into multiple variables.
Updated everything to build with this change.
