diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index 0d04bbc..e1f2bff 100644
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -2870,12 +2870,20 @@ asm_clobber_reg_is_valid (int regno, int nregs, const char *regname)
     {
       /* ??? Diagnose during gimplification?  */
       error ("PIC register clobbered by %qs in %<asm%>", regname);
+      error ("Such clobbers are not supported by GCC. "
+	     "If you really want to overwrite the PIC register, "
+	     "remove it from the clobber list in the %<asm%> at your own risk: "
+	     "GCC will not save it.");
       is_valid = false;
     }
   /* Clobbering the STACK POINTER register is an error.  */
   if (overlaps_hard_reg_set_p (regset, Pmode, STACK_POINTER_REGNUM))
     {
       error ("Stack Pointer register clobbered by %qs in %<asm%>", regname);
+      error ("Such clobbers are not supported by GCC. "
+	     "If you really want to overwrite the Stack Pointer, "
+	     "remove it from the clobber list in the %<asm%> at your own risk: "
+	     "GCC will not save it.");
       is_valid = false;
     }