diff --git a/configure b/configure
index 70d2c4b..ba94e2a 100755
--- a/configure
+++ b/configure
@@ -799,6 +799,7 @@ enable_fast_install
 with_gnu_ld
 enable_libtool_lock
 enable_largefile
+enable_werror
 with_system_libunwind
 enable_host_shared
 '
@@ -1445,6 +1446,7 @@ Optional Features:
                           optimize for fast installation [default=yes]
   --disable-libtool-lock  avoid locking (might break parallel builds)
   --disable-largefile     omit support for large files
+  --disable-werror        disable building with -Werror
   --enable-host-shared    build host code as shared libraries
 
 Optional Packages:
@@ -7777,23 +7779,25 @@ _LT_EOF
 fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_force_load" >&5
 $as_echo "$lt_cv_ld_force_load" >&6; }
-    case $host_os in
-    rhapsody* | darwin1.[012])
+    # Allow for Darwin 4-7 (macOS 10.0-10.3) although these are not expect to
+    # build without first building modern cctools / linker.
+    case $host_cpu-$host_os in
+    *-rhapsody* | *-darwin1.[012])
       _lt_dar_allow_undefined='${wl}-undefined ${wl}suppress' ;;
-    darwin1.*)
+    *-darwin1.*)
       _lt_dar_allow_undefined='${wl}-flat_namespace ${wl}-undefined ${wl}suppress' ;;
-    darwin*) # darwin 5.x on
-      # if running on 10.5 or later, the deployment target defaults
-      # to the OS version, if on x86, and 10.4, the deployment
-      # target defaults to 10.4. Don't you love it?
-      case ${MACOSX_DEPLOYMENT_TARGET-10.0},$host in
-	10.0,*86*-darwin8*|10.0,*-darwin[91]*)
-	  _lt_dar_allow_undefined='${wl}-undefined ${wl}dynamic_lookup' ;;
+    *-darwin*)
+      # darwin 5.x (macOS 10.1) onwards we only need to adjust when the
+      # deployment target is forced to an earlier version.
+      case ${MACOSX_DEPLOYMENT_TARGET-UNSET},$host in
+	UNSET,*-darwin[89]*|UNSET,*-darwin[12][0123456789]*)
+	  ;;
 	10.[012][,.]*)
-	  _lt_dar_allow_undefined='${wl}-flat_namespace ${wl}-undefined ${wl}suppress' ;;
-	10.*)
-	  _lt_dar_allow_undefined='${wl}-undefined ${wl}dynamic_lookup' ;;
-      esac
+	  _lt_dar_allow_undefined='${wl}-flat_namespace ${wl}-undefined ${wl}suppress'
+	  ;;
+	*)
+	  ;;
+     esac
     ;;
   esac
     if test "$lt_cv_apple_cc_single_mod" = "yes"; then
@@ -9562,7 +9566,7 @@ if test -z "$aix_libpath"; then aix_libpath="/usr/lib:/lib"; fi
       if test "$GCC" = yes && test "$with_gnu_ld" = no; then
 	case $host_cpu in
 	hppa*64*)
-	  archive_cmds='$CC -shared ${wl}+h ${wl}$soname -o $lib $libobjs $deplibs $compiler_flags'
+	  archive_cmds='$CC -shared ${wl}+h ${wl}$soname ${wl}+nodefaultrpath -o $lib $libobjs $deplibs $compiler_flags'
 	  ;;
 	ia64*)
 	  archive_cmds='$CC -shared -fPIC ${wl}+h ${wl}$soname ${wl}+nodefaultrpath -o $lib $libobjs $deplibs $compiler_flags'
@@ -9574,7 +9578,7 @@ if test -z "$aix_libpath"; then aix_libpath="/usr/lib:/lib"; fi
       else
 	case $host_cpu in
 	hppa*64*)
-	  archive_cmds='$CC -b ${wl}+h ${wl}$soname -o $lib $libobjs $deplibs $compiler_flags'
+	  archive_cmds='$CC -b ${wl}+h ${wl}$soname ${wl}+nodefaultrpath -o $lib $libobjs $deplibs $compiler_flags'
 	  ;;
 	ia64*)
 	  archive_cmds='$CC -b ${wl}+h ${wl}$soname ${wl}+nodefaultrpath -o $lib $libobjs $deplibs $compiler_flags'
@@ -10458,16 +10462,6 @@ freebsd* | dragonfly*)
   esac
   ;;
 
-gnu*)
-  version_type=linux
-  need_lib_prefix=no
-  need_version=no
-  library_names_spec='${libname}${release}${shared_ext}$versuffix ${libname}${release}${shared_ext}${major} ${libname}${shared_ext}'
-  soname_spec='${libname}${release}${shared_ext}$major'
-  shlibpath_var=LD_LIBRARY_PATH
-  hardcode_into_libs=yes
-  ;;
-
 haiku*)
   version_type=linux
   need_lib_prefix=no
@@ -10589,7 +10583,7 @@ linux*oldld* | linux*aout* | linux*coff*)
 # project, but have not yet been accepted: they are GCC-local changes
 # for the time being.  (See
 # https://lists.gnu.org/archive/html/libtool-patches/2018-05/msg00000.html)
-linux* | k*bsd*-gnu | kopensolaris*-gnu | uclinuxfdpiceabi)
+linux* | k*bsd*-gnu | kopensolaris*-gnu | gnu* | uclinuxfdpiceabi)
   version_type=linux
   need_lib_prefix=no
   need_version=no
@@ -11278,7 +11272,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11281 "configure"
+#line 11275 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11384,7 +11378,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11387 "configure"
+#line 11381 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11979,7 +11973,12 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
-if test -n "${with_target_subdir}"; then
+# Check whether --enable-werror was given.
+if test "${enable_werror+set}" = set; then :
+  enableval=$enable_werror;
+fi
+
+if test "x$enable_werror" != "xno" && test -n "${with_target_subdir}"; then :
   WARN_FLAGS="$WARN_FLAGS -Werror"
 fi
 
diff --git a/configure.ac b/configure.ac
index 9ee1392..f0b1bdb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -145,9 +145,10 @@ ACX_PROG_CC_WARNING_OPTS([-W -Wall -Wwrite-strings -Wstrict-prototypes \
 			  -Wmissing-format-attribute -Wcast-qual],
 			  [WARN_FLAGS])
 
-if test -n "${with_target_subdir}"; then
-  WARN_FLAGS="$WARN_FLAGS -Werror"
-fi
+AC_ARG_ENABLE([werror],
+  [AS_HELP_STRING([--disable-werror], [disable building with -Werror])])
+AS_IF([test "x$enable_werror" != "xno" && test -n "${with_target_subdir}"],
+  [WARN_FLAGS="$WARN_FLAGS -Werror"])
 
 AC_SUBST(WARN_FLAGS)