diff --git a/m4/ax_gcc_archflag.m4 b/m4/ax_gcc_archflag.m4
index c115a6aaf94d93aeee9c0a26d4e1bcede616c46d..ef8e7c199da1622354a029ec142386b7f1f9e442 100644
--- a/m4/ax_gcc_archflag.m4
+++ b/m4/ax_gcc_archflag.m4
@@ -109,7 +109,7 @@ case $host_cpu in
 	    *3?6[[ae]]?:*:*:*) ax_gcc_arch="ivybridge core-avx-i corei7-avx corei7 core2 pentium-m pentium3 pentiumpro" ;;
 	    *3?6[[cf]]?:*:*:*|*4?6[[56]]?:*:*:*) ax_gcc_arch="haswell core-avx2 core-avx-i corei7-avx corei7 core2 pentium-m pentium3 pentiumpro" ;;
 	    *3?6d?:*:*:*|*4?6[[7f]]?:*:*:*|*5?66?:*:*:*) ax_gcc_arch="broadwell core-avx2 core-avx-i corei7-avx corei7 core2 pentium-m pentium3 pentiumpro" ;;
-	    *4?6[[de]]?:*:*:*) ax_gcc_arch="skylake haswell sandybridge core-avx2 core-avx-i corei7-avx corei7 core2 pentium-m pentium3 pentiumpro" ;;	
+	    *4?6[[de]]?:*:*:*|*5?6[[de]]?:*:*:*) ax_gcc_arch="skylake haswell sandybridge core-avx2 core-avx-i corei7-avx corei7 core2 pentium-m pentium3 pentiumpro" ;;	
 	    *5?6[[56]]?:*:*:*) ax_gcc_arch="skylake-avx512 skylake haswell sandybridge core-avx2 core-avx-i corei7-avx corei7 core2 pentium-m pentium3 pentiumpro" ;;	
             *8?6[[de]]?:*:*:*|*9?6[[de]]?:*:*:*) ax_gcc_arch="kabylake skylake broadwell haswell sandybridge core-avx2 core-avx-i corei7-avx corei7 core2 pentium-m pentium3 pentiumpro" ;;
 	    *1?6c?:*:*:*|*2?6[[67]]?:*:*:*|*3?6[[56]]?:*:*:*) ax_gcc_arch="bonnell atom core2 pentium-m pentium3 pentiumpro" ;;