Index: share/mk/bsd.compiler.mk
===================================================================
--- share/mk/bsd.compiler.mk
+++ share/mk/bsd.compiler.mk
@@ -19,7 +19,9 @@
 # COMPILER_FEATURES will contain one or more of the following, based on
 # compiler support for that feature:
 #
-# - c++11 : supports full (or nearly full) C++11 programming environment.
+# - c++11:     supports full (or nearly full) C++11 programming environment.
+# - retpoline: supports the retpoline speculative execution vulnerability
+#              mitigation.
 #
 # These variables with an X_ prefix will also be provided if XCC is set.
 #
@@ -178,11 +180,13 @@
 .endif
 .endif
 
+${X_}COMPILER_FEATURES=
 .if ${${X_}COMPILER_TYPE} == "clang" || \
 	(${${X_}COMPILER_TYPE} == "gcc" && ${${X_}COMPILER_VERSION} >= 40800)
-${X_}COMPILER_FEATURES=	c++11
-.else
-${X_}COMPILER_FEATURES=
+${X_}COMPILER_FEATURES+=	c++11
+.endif
+.if ${${X_}COMPILER_TYPE} == "clang" && ${${X_}COMPILER_VERSION} >= 60000
+${X_}COMPILER_FEATURES+=	retpoline
 .endif
 
 .else
Index: share/mk/bsd.linker.mk
===================================================================
--- share/mk/bsd.linker.mk
+++ share/mk/bsd.linker.mk
@@ -12,7 +12,9 @@
 # LINKER_FEATURES may contain one or more of the following, based on
 # linker support for that feature:
 #
-# - build-id : support for generating a Build-ID note
+# - build-id:  support for generating a Build-ID note
+# - retpoline: support for generating PLT with retpoline speculative
+#              execution vulnerability mitigation
 #
 # These variables with an X_ prefix will also be provided if XLD is set.
 #
@@ -70,6 +72,9 @@
 .if ${${X_}LINKER_TYPE} != "bfd" || ${${X_}LINKER_VERSION} > 21750
 ${X_}LINKER_FEATURES+=	build-id
 .endif
+.if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 60000
+${X_}LINKER_FEATURES+=	retpoline
+.endif
 .endif
 .else
 # Use LD's values