diff --git a/Eigen/src/Core/products/GeneralBlockPanelKernel.h b/Eigen/src/Core/products/GeneralBlockPanelKernel.h
index bcb332cb9..1197fec94 100644
--- a/Eigen/src/Core/products/GeneralBlockPanelKernel.h
+++ b/Eigen/src/Core/products/GeneralBlockPanelKernel.h
@@ -1389,11 +1389,10 @@ void gebp_kernel<LhsScalar,RhsScalar,Index,DataMapper,mr,nr,ConjugateLhs,Conjuga
             EIGEN_ASM_COMMENT("begin gebp micro kernel 2pX4");
             RhsPacket B_0, B1, B2, B3, T0;
 
-  
           // NOTE: the begin/end asm comments below work around bug 935!
           // but they are not enough for gcc>=6 without FMA (bug 1637)
           #if EIGEN_GNUC_AT_LEAST(6,0)
-            #define EIGEN_GEBP_2PX4_SPILLING_WORKAROUND asm("" : [a0] "+x" (A0), [a1] "+x" (A1) );
+            #define EIGEN_GEBP_2PX4_SPILLING_WORKAROUND __asm__  ("" : [a0] "+rm" (A0),[a1] "+rm" (A1));
           #else
             #define EIGEN_GEBP_2PX4_SPILLING_WORKAROUND
           #endif