Revert "ruby: disable stack protector"

This reverts commit dce880b425.

srcpkgs/ruby/template

@@ -3,7 +3,7 @@ _ruby_abiver=2.5.0
 
 pkgname=ruby
 version=2.5.0
-revision=2
+revision=3
 build_style=gnu-configure
 configure_args="--enable-shared --disable-rpath
  DOXYGEN=/usr/bin/doxygen DOT=/usr/bin/dot PKG_CONFIG=/usr/bin/pkg-config"
@@ -41,9 +41,10 @@ pre_build() {
 	# Hack for cross-builds.
 	touch ext/ripper/check
 	if [ "$XBPS_GCC_VERSION_MAJOR" -ge 7 ]; then
-		# Disable stack protector: it causes unexpected behaviours with native libraries (subtle, vagrant)
+		# Set -fno-stack-protector for i686* or otherwise linking fails with
+		# ...: undefined reference to '__stack_chk_fail_local'
 		case "$XBPS_TARGET_MACHINE" in
-			*) sed -i Makefile \
+			i686*) sed -i Makefile \
 					-e "s;-fstack-protector-strong;;" \
 					-e "s;-fstack-protector;-fno-stack-protector;"
 				;;