--- a/toolchain.eclass	2018-08-24 17:37:37.373852897 +0200
+++ b/toolchain.eclass	2018-08-24 17:30:38.844994123 +0200
@@ -1622,6 +1622,11 @@
 	[[ ! -x /usr/bin/perl ]] \
 		&& find "${WORKDIR}"/build -name '*.[17]' -exec touch {} +
 
+	# Older gcc versions did not detect bash and re-exec itself, so force the
+	# use of bash.  Newer ones will auto-detect, but this is not harmeful.
+	# This needs to be set for compile as well, as it's used in libtool
+	# generation, which will break install otherwise (at least in 3.3.6).
+	CONFIG_SHELL="${EPREFIX}/bin/bash" \
 	gcc_do_make ${GCC_MAKE_TARGET}
 }