--- a/Makefile
+++ b/Makefile
@@ -90,18 +90,6 @@ else
   ## OS detection.  Comment out if gmake syntax not supported by other 'make'. 
   OSNAME:=$(shell uname -s)
   ARCH ?= $(shell uname -m)
-  ifeq ($(OSNAME),Linux)
-    # Not all CPU architectures support "-march" or "-march=native".
-    #   - Supported    : x86, x86_64, ARM, AARCH64, riscv64, etc..
-    #   - Not Supported: IBM Power, etc...
-    ifeq ($(ARCH),$(filter $(ARCH),ppc64 ppc64le))
-        OPTON += -mcpu=native -mtune=native
-    else ifeq ($(ARCH),riscv64)
-        OPTON += -march=rv64g -mabi=lp64d
-    else
-        OPTON += -march=native -mtune=native
-    endif
-  endif
 
   ifeq ($(OSNAME),Darwin)
     # (adjust flags or comment out this section for older versions of XCode or OS X)