--- a/eclass/toolchain.eclass	
+++ a/eclass/toolchain.eclass	
@@ -153,7 +153,7 @@ if [[ ${PN} != "kgcc64" && ${PN} != gcc-* ]] ; then
 	# the older versions, we don't want to bother supporting it.  #448024
 	tc_version_is_at_least 4.8 && IUSE+=" graphite" IUSE_DEF+=( sanitize )
 	tc_version_is_at_least 4.9 && IUSE+=" cilk"
-	tc_version_is_at_least 5.0 && IUSE+=" jit"
+	tc_version_is_at_least 5.0 && IUSE+=" jit mpx"
 	tc_version_is_at_least 6.0 && IUSE+=" pie +ssp"
 fi
 
@@ -1161,6 +1161,14 @@ toolchain_src_configure() {
 		fi
 	fi
 
+	if tc_version_is_at_least 5.0 ; then
+		if in_iuse mpx ; then
+			confgcc+=( $(use_enable mpx libmpx ) )
+		else
+			confgcc+=( --disable-libmpx )
+		fi
+	fi
+
 	if in_iuse cilk ; then
 		confgcc+=( $(use_enable cilk libcilkrts) )
 	fi
--- a/profiles/use.local.desc	
+++ a/profiles/use.local.desc	
@@ -7525,6 +7525,7 @@ sys-devel/gcc:go - Build the GCC Go language frontend.
 sys-devel/gcc:graphite - Add support for the framework for loop optimizations based on a polyhedral intermediate representation
 sys-devel/gcc:jit - Enable libgccjit so other applications can embed gcc for Just-In-Time compilation. This will slow down the compiler a bit as it forces all of the toolchain to be shared libs.
 sys-devel/gcc:libssp - Build SSP support into a dedicated library rather than use the code in the C library (DO NOT ENABLE THIS IF YOU DON'T KNOW WHAT IT DOES)
+sys-devel/gcc:mpx - Add compiler support for Intel Memory Protection Extensions (MPX)
 sys-devel/gcc:mudflap - Add support for mudflap, a pointer use checking library
 sys-devel/gcc:multislot - Allow for multiple versions to be emerged at once for same CTARGET
 sys-devel/gcc:nopie - Disable PIE support (NOT FOR GENERAL USE)