pkg/59448: make replace of pkg_install fails in libfetch with -inet6 option

[smallm%sdf.org@localhost]

>Number:         59448
>Category:       pkg
>Synopsis:       make replace of pkg_install fails in libfetch with -inet6 option
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu May 29 03:25:00 +0000 2025
>Originator:     Michael Small
>Release:        pkgsrc-2025Q1 on 2025-05-03
>Organization:
>Environment:
NetBSD misty.Mauritania 10.1_STABLE NetBSD 10.1_STABLE (GENERIC) #0: Mon Jan 13 01:20:57 EST 2025  smallm@misty.Mauritania:/usr/obj/sys/arch/amd64/compile/GENERIC amd64
>Description:
A make replace of pkgtools/pkg_install at the start of a pkg_rolling-replace from pkgsrc-2024-Q4 to 2025-Q1 gave this error from a libfetch source file:

#   compile  libfetch/ftp.o
gcc -O2 -I/usr/include -DHAVE_NBCOMPAT_H=1 -I/usr/pkg/include   -std=gnu99    -Wall -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Wno-sign-compare  -Wsystem-headers   -Wno-traditional   -Wa,--fatal-warnings  -Wreturn-type -Wswitch -Wshadow -Wcast-qual -Wwrite-strings -Wextra -Wno-unused-parameter -Wno-sign-compare -Wsign-compare -Wformat=2  -Wno-format-zero-length  -Werror   -fPIE   -D_LARGEFILE_SOURCE -D_LARGE_FILES -D_FILE_OFFSET_BITS=64 -DDEF_UMASK=0022 -I/usr/pkgsrc/work/pkgtools/pkg_install/work/libfetch -I/usr/pkgsrc/work/pkgtools/pkg_install/work -I/usr/include -DHAVE_NBCOMPAT_H=1 -I/usr/pkg/include -I. -D_LARGEFILE_SOURCE -D_LARGE_FILES -D_FILE_OFFSET_BITS=64 -DWITH_SSL -DFTP_COMBINE_CWDS  -c    ftp.c -o ftp.o.o
ftp.c: In function 'ftp_transfer':
ftp.c:862:8: error: unused variable 'hname' [-Werror=unused-variable]
  862 |   char hname[INET6_ADDRSTRLEN];
      |        ^~~~~
cc1: all warnings being treated as errors
*** Error code 1

/etc/mk.conf on my machine has -inet6:

PKG_DEFAULT_OPTIONS= sasl tls zlib -cups -bluray -lua -wayland ghostscript \
	vorbis theora libmpg123 -mad -pulseaudio oss -v4l2 xvid x264 \
	-skey sun readline -iscsi -inet6 -bzip2 -libusb-1 -ldap \
	imagemagick svg -llvm-target-aarch64 -llvm-target-amdgpu \
	-llvm-target-bpf -llvm-target-mips \
	-llvm-target-powerpc -llvm-target-sparc \
	-llvm-target-systemz -gcc-fortran -gcc-objc++ -gcc-objc \
	-gtk3-atk-bridge -exim-appendfile-maildir -exim-appendfile-mailstore \
	-exim-appendfile-mbx -exim-content-scan -exim-lookup-dsearch \
	-exim-old-demime -exim-tcp-wrappers -javascript -xinerama xaw3d -gtk3 \
	-svg -dbus -acl -webrtc

If I make install from within net/libfetch directly, there's no error, but it seems not to run with a warnings as errors flag.

>How-To-Repeat:
Set the -inet6 option and make replace pkg_install.
>Fix:
--- net/libfetch/files/ftp.c.orig	2025-04-27 21:34:41.465046812 -0400
+++ net/libfetch/files/ftp.c	2025-05-16 23:18:07.221628027 -0400
@@ -859,8 +859,9 @@ retry_mode:
 		int low = CHECK_FLAG('l');
 #endif
 		int d;
+#ifdef IPV6
 		char hname[INET6_ADDRSTRLEN];
-
+#endif
 		switch (u.ss.ss_family) {
 		case AF_INET6:
 			u.sin6.sin6_port = 0;