Only in binutils-2.34/gold: autom4te.cache
diff -rup binutils.orig/gold/configure binutils-2.34/gold/configure
--- binutils.orig/gold/configure	2020-04-20 12:35:13.048297305 +0100
+++ binutils-2.34/gold/configure	2020-04-20 14:02:06.743725696 +0100
@@ -5180,7 +5180,8 @@ for targ in $target $canon_targets; do
     . ${srcdir}/configure.tgt
 
     if test "$targ_obj" = "UNKNOWN"; then
-      as_fn_error $? "\"unsupported target $targ\"" "$LINENO" 5
+      { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: \"unsupported target $targ\"" >&5
+$as_echo "$as_me: WARNING: \"unsupported target $targ\"" >&2;}
     else
       targetobjs="$targetobjs ${targ_obj}.\$(OBJEXT)"
       if test "$targ_extra_obj" != ""; then
diff -rup binutils.orig/gold/configure.ac binutils-2.34/gold/configure.ac
--- binutils.orig/gold/configure.ac	2020-04-20 12:35:13.050297291 +0100
+++ binutils-2.34/gold/configure.ac	2020-04-20 14:01:46.435868770 +0100
@@ -181,7 +181,7 @@ for targ in $target $canon_targets; do
     . ${srcdir}/configure.tgt
 
     if test "$targ_obj" = "UNKNOWN"; then
-      AC_MSG_ERROR("unsupported target $targ")
+      AC_MSG_WARN("unsupported target $targ")
     else
       targetobjs="$targetobjs ${targ_obj}.\$(OBJEXT)"
       if test "$targ_extra_obj" != ""; then
--- binutils.orig/ld/configure.tgt	2020-04-20 12:35:12.465301359 +0100
+++ binutils-2.34/ld/configure.tgt	2020-04-20 14:17:52.123066333 +0100
@@ -220,7 +220,7 @@ bfin-*-linux-uclibc*)	targ_emul=elf32bfi
 			targ_extra_emuls="elf32bfin"
 			targ_extra_libpath=$targ_extra_emuls
 			;;
-bpf-*-*)		targ_emul=elf64bpf
+bpf-* | bpf-*-*)	targ_emul=elf64bpf
 			;;
 cr16-*-elf*)		targ_emul=elf32cr16
 			;;
@@ -1026,7 +1026,7 @@ z8k-*-coff)		targ_emul=z8002
 			targ_extra_ofiles=
 			;;
 *)
-  echo 2>&1 "*** ld does not support target ${targ}"
+  echo 2>&1 "*** ld does not support target '${targ}' NO REALLY"
   echo 2>&1 "*** see ld/configure.tgt for supported targets"
   exit 1
 
--- binutils.orig/bfd/config.bfd	2020-04-20 12:35:13.038297375 +0100
+++ binutils-2.34/bfd/config.bfd	2020-04-20 14:25:26.452869193 +0100
@@ -473,7 +473,7 @@ case "${targ}" in
     ;;
 
 #ifdef BFD64
-  bpf-*-none)
+  bpf-*-none | bpf-*)
     targ_defvec=bpf_elf64_le_vec
     targ_selvecs=bpf_elf64_be_vec
     targ_underscore=yes
@@ -1427,7 +1427,7 @@ case "${targ}" in
     ;;
 
   *)
-    echo 1>&2 "*** BFD does not support target ${targ}."
+    echo 1>&2 "*** BFD does not support target '${targ}'.  Honest."
     echo 1>&2 "*** Look in bfd/config.bfd for supported targets."
     exit 1
     ;;