diff --git a/Makefile.prebuild b/Makefile.prebuild
index b7d695a..4069032 100644
--- a/Makefile.prebuild
+++ b/Makefile.prebuild
@@ -72,7 +72,7 @@ TARGET_FLAGS = -march=rv64imafdcv -mabi=lp64d
 endif
 
 ifeq ($(TARGET), RISCV64_GENERIC)
-TARGET_FLAGS = -march=rv64imafdc -mabi=lp64d
+#TARGET_FLAGS = -march=rv64imafdc -mabi=lp64d
 endif
 
 all: getarch_2nd
diff --git a/Makefile.riscv64 b/Makefile.riscv64
index 9f6e48b..a6b1a3f 100644
--- a/Makefile.riscv64
+++ b/Makefile.riscv64
@@ -15,6 +15,6 @@ CCOMMON_OPT += -march=rv64imafdcv -mabi=lp64d
 FCOMMON_OPT += -march=rv64imafdcv -mabi=lp64d
 endif
 ifeq ($(CORE), RISCV64_GENERIC)
-CCOMMON_OPT += -march=rv64imafdc -mabi=lp64d
-FCOMMON_OPT += -march=rv64imafdc -mabi=lp64d
+#CCOMMON_OPT += -march=rv64imafdc -mabi=lp64d
+#FCOMMON_OPT += -march=rv64imafdc -mabi=lp64d
 endif
diff --git a/Makefile.system b/Makefile.system
index b065f9a..b4abaff 100644
--- a/Makefile.system
+++ b/Makefile.system
@@ -202,7 +202,7 @@ endif
 # On x86_64 build getarch with march=native unless the compiler is PGI. This is required to detect AVX512 support in getarch.
 ifeq ($(HOSTARCH), x86_64)
 ifeq ($(findstring pgcc,$(HOSTCC))$(findstring nvc,$(HOSTCC)),)
-GETARCH_FLAGS += -march=native
+#GETARCH_FLAGS += -march=native
 endif
 endif
 
@@ -1416,7 +1416,7 @@ ifeq ($(NEED_PIC), 1)
 ifeq ($(C_COMPILER), IBM)
 CCOMMON_OPT += -qpic=large
 else
-CCOMMON_OPT += -fPIC
+#CCOMMON_OPT += -fPIC
 endif
 ifeq ($(F_COMPILER), SUN)
 FCOMMON_OPT  += -pic
@@ -1683,7 +1683,7 @@ FCOMMON_OPT += -g
 endif
 
 ifndef COMMON_OPT
-COMMON_OPT = -O2
+COMMON_OPT = -O3
 endif
 
 ifndef FCOMMON_OPT