port-amd64/55367: failure to compile amd64 current with clang

[rares.aioanei%gmail.com@localhost]

>Number:         55367
>Category:       port-amd64
>Synopsis:       failure to compile amd64 current with clang
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    port-amd64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jun 11 08:55:00 +0000 2020
>Originator:     Rares Aioanei
>Release:        CURRENT
>Organization:
>Environment:
>Description:
This happens since the 9th of June, while cross-compiling on a FreeBSD amd64 box : 

#   compile  drvctl/drvctl.o                                                                                                                                                                  
/stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/x86_64--netbsd-clang -O2   -fPIE   -std=gnu99     -Wno-sign-compare -Wno-pointer-sign  -Wall -Wstrict
-prototypes -Wmissing-prototypes -Wpointer-arith -Wno-sign-compare    -Wreturn-type -Wswitch -Wshadow -Wcast-qual -Wwrite-strings -Wextra -Wno-unused-parameter -Wno-sign-compare -Wold-style-
definition -Wsign-compare -Wformat=2   -Wpointer-sign -Wmissing-noreturn  -Werror     --sysroot=/stpool/devel/netbsd/current/amd64/usr/src/obj/destdir.amd64  -c    /stpool/devel/netbsd/curre
nt/amd64/usr/src/sbin/drvctl/drvctl.c                                                                                                                                                         
/stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/nbctfconvert -g -L VERSION drvctl.o                                                                  
#      link  drvctl/drvctl                                                                                                                                                                    
/stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/x86_64--netbsd-clang    --sysroot=/stpool/devel/netbsd/current/amd64/usr/src/obj/destdir.amd64   -pie
  -Wl,--fatal-warnings -Wl,--warn-shared-textrel -Wl,-z,relro     -o drvctl  drvctl.o  -Wl,-dynamic-linker=/libexec/ld.elf_so -Wl,-rpath,/lib  -L=/lib -lprop                                 
/stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/x86_64--netbsd-ld: drvctl.o: in function `main':                                                     
drvctl.c:(.text+0x233): warning: this program uses prop_string_create_cstring(); all functions supporting mutable prop_strings are deprecated.                                                
/stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/x86_64--netbsd-ld: drvctl.c:(.text+0x20e): warning: this program uses prop_string_create_cstring_noco
py(), which is deprecated; use prop_string_create_nocopy() instead.                                                                                                                           
/stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/x86_64--netbsd-ld: drvctl.o: in function `display_object':                                           
drvctl.c:(.text+0x953): warning: this program uses prop_string_cstring_nocopy(), which is deprecated; use prop_string_value() instead.
/stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/x86_64--netbsd-ld: drvctl.o: in function `main':                                                     drvctl.c:(.text+0x2b4): warning: this program uses prop_number_integer_value(), which is deprecated; use prop_number_signed_value() instead.                                                  x86_64--netbsd-clang: error: linker command failed with exit code 1 (use -v to see invocation)                                                                                                
                                               
*** Failed target:  drvctl
*** Failed command: /stpool/devel/netbsd/current/amd64/usr/src/obj/tooldir.FreeBSD-12.1-RELEASE-p5-amd64/bin/x86_64--netbsd-clang --sysroot=/stpool/devel/netbsd/current/amd64/usr/src/obj/des
tdir.amd64 -pie -Wl,--fatal-warnings -Wl,--warn-shared-textrel -Wl,-z,relro -o drvctl drvctl.o -Wl,-dynamic-linker=/libexec/ld.elf_so -Wl,-rpath,/lib -L=/lib -lprop 
*** Error code 1

>How-To-Repeat:

>Fix: