diff --git a/eclass/toolchain.eclass b/eclass/toolchain.eclass
index d29d070805820..939c681131889 100644
--- a/eclass/toolchain.eclass
+++ b/eclass/toolchain.eclass
@@ -402,7 +402,7 @@ if tc_has_feature valgrind ; then
 fi
 
 if [[ ${PN} != gnat-gpl ]] && tc_has_feature ada ; then
-	BDEPEND+=" ada? ( || ( sys-devel/gcc[ada] dev-lang/gnat-gpl[ada] ) )"
+	BDEPEND+=" ada? ( || ( sys-devel/gcc:${SLOT}[ada] <sys-devel/gcc-${SLOT}[ada] dev-lang/gnat-gpl[ada] ) )"
 fi
 
 # TODO: Add a pkg_setup & pkg_pretend check for whether the active compiler
@@ -411,7 +411,7 @@ if tc_has_feature d && tc_version_is_at_least 12.0 ; then
 	# D in 12+ is self-hosting and needs D to bootstrap.
 	# TODO: package some binary we can use, like for Ada
 	# bug #840182
-	BDEPEND+=" d? ( || ( sys-devel/gcc[d(-)] <sys-devel/gcc-12[d(-)] ) )"
+	BDEPEND+=" d? ( || ( sys-devel/gcc:${SLOT}[d(-)] <sys-devel/gcc-${SLOT}[d(-)] <sys-devel/gcc-12[d(-)] ) )"
 fi
 
 if tc_has_feature rust && tc_version_is_at_least 14.0.0_pre20230421 ; then