--- a/gcc-7.3.0-r3.ebuild	2018-06-08 15:26:00.000000000 +0200
+++ b/gcc-7.3.0-r4.ebuild	2018-06-11 14:46:23.113324400 +0200
@@ -78,6 +78,12 @@
 		;;
 	esac
 
+	if [[ ${CHOST} == *-cygwin* ]]; then
+		# use built-in SSP with Cygwin 2.10
+		# FIXME: --disable-libssp should suffice in GCC 8
+		export gcc_cv_libc_provides_ssp=yes
+	fi
+
 	# Since GCC 4.1.2 some non-posix (?) /bin/sh compatible code is used, at
 	# least on Solaris, and AIX /bin/sh is way too slow,
 	# so force it to use $BASH (that portage uses) - it can't be EPREFIX